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SDLRC - Scientific Articles all years by Author - He-Hn


The Sheahan Diamond Literature Reference Compilation
The Sheahan Diamond Literature Reference Compilation is compiled by Patricia Sheahan who publishes on a monthly basis a list of new scientific articles related to diamonds as well as media coverage and corporate announcementscalled the Sheahan Diamond Literature Service that is distributed as a free pdf to a list of followers. Pat has kindly agreed to allow her work to be made available as an online digital resource at Kaiser Research Online so that a broader community interested in diamonds and related geology can benefit. The references are for personal use information purposes only; when available a link is provided to an online location where the full article can be accessed or purchased directly. Reproduction of this compilation in part or in whole without permission from the Sheahan Diamond Literature Service is strictly prohibited. Return to Diamond Resource Center
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Media/Corporate References by Name for all years
A B C D-Diam Diamonds Diamr+ E F G H I J K L M N O P Q R S T U V W X Y Z
Tips for Users
Posted/Published Reference CodesThe SDLRC provides 3 types of references identified in the reference code. DS for scientific article, DM for a media article, and DC for a corporate announcement. Consider DS0512-0001. The DS stands for "diamond scientific". 05 stands for 2005, the year the reference was posted. 12 represents the month the reference was posted. For all years prior to 2015 the default month is 12. -0001 is the reference's identifier and it does not mean anything. The number below the refence code, ie 2015, is the year the article was published. Note that the posted year may sometimes be later than the published year.
Sort OrderReferences are sorted by the "author" name and when the reference was posted to the compilation.
Most RecentIf the reference code is highlighted yellow, the reference was made available through the most recent monthly compilation of new literature. Use this to check out new references. When new references are posted, we make it our priority to track down an online link and obtain an abstract. With regard to older references, tracking down an abstract and an online link is a work in progress.
Link to external location of article: If the title has a link, it means we have found a location online where you can either retrieve the full article free, or purchase access to it. The Sheahan Diamond Literature Service is not a technical article procurement service; if you want a restricted article, you must deal directly with the vendor who controls the copyright to the article.
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Sending or sharing a referenceThe left column (Posted/Published) has an embedded hyperlink for each reference. In Firefox, if you right click on it, you can obtain the link url for that reference's location within the page, which you can copy and paste into an email or any other document. You can also use the "share this link" option to tweet, facebook etc the link.
Author Index
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years - He-Hn
Posted/
Published
AuthorTitleSourceRegionKeywords
DS2003-0566
2003
He, B.He, B., Xu, Y.G., Chung, S.L., Xiao, L., Wang, Y.Sedimentary evidence for a rapid kilometer scale crustal doming prior to eruption of theEarth and Planetary Science Letters, Vol. 213, 3-4, pp. 391-405.GlobalBasalts - not specific to diamonds, tectonics
DS200412-0808
2003
He, B.He, B., Xu, Y.G., Chung, S.L., Xiao, L., Wang, Y.Sedimentary evidence for a rapid kilometer scale crustal doming prior to eruption of the Emeishan flood basalts.Earth and Planetary Science Letters, Vol. 213, 3-4, pp. 391-405.TechnologyBasalts - not specific to diamonds Tectonics
DS200512-1204
2004
He, B.Xiao, L., Xu, Y.G., Mei, H.J., Zheng, Y.F., He, B., Pirajno, F.Distinct mantle sources of low Ti and high Ti basalts from the western Emeishan large igneous province, SW China: implications for plume?? lithosphere interactionEarth and Planetary Science Letters, Vol. 228, 3-4, pp. 525-546.ChinaMantle mineralogy, titanium
DS200712-1133
2007
He, B.Wang, Q., Wyman, D.A., Xu, J., Jian, P., Zhao, Z., Li, C., Xu, W., Ma, J., He, B.Early Cretaceous adakitic granites in the northern Dabie Complex, central China: implications for partial melting and delamination of thickened lower crust.Geochimica et Cosmochimica Acta, Vol. 71, 10, May 15, pp. 2609-2636.ChinaUHP - Dabie Shon
DS201012-0440
2010
He, B.Li, J.,Xu, J-F., Suzuki, K., He, B., Xu, Y-G., Ren, Z-Y.Os, Nd and Sr isotope and trace element geochemistry of the Muli picrites: insights into the mantle source of the Emeishan large igneous province.Lithos, in press available, 15p.ChinaGeochronology
DS201312-0536
2014
He, B.Li, J., Wang,-C., Ren, Z-Y., Xu, J-F., He, B., Xu, Y-G.Chemical heterogeneity of the Emeishan mantle plume: evidence from highly siderophile element abundances in picrites.Journal of Asian Earth Studies, Vol. 79, A, pp. 191-205.ChinaPicrite
DS201703-0406
2017
He, D.He, D., Liu, Y., Gao, C., Chen, C., Hu, Z., Gao, S.SiC dominated ultra-reduced mineral assemblage in carbonatitic xenoliths from the Dalihu basalt, Inner Mongolia, China.American Mineralogist, Vol. 102, pp. 312-320.China, MongoliaCarbonatite

Abstract: SiC and associated ultra-reduced minerals were reported in various geological settings, however, their genesis and preservation mechanism are poorly understood. Here, we reported a SiC-dominated ultra-reduced mineral assemblage, including SiC, TiC, native metals (Si, Fe, and Ni) and iron silicide, from carbonatitic xenoliths in Dalihu, Inner Mongolia. All minerals were identified in situ in polished/thin sections. SiC is 20-50 ?m in size, blue to colorless in color, and usually identified in the micro-cavities within the carbonatitic xenolith. Four types of SiC polytypes were identified, which are dominated by ?-SiC (3C polytype) and 4H polytype followed by 15R and 6H. These SiC are featured by 13C-depleted isotopic compositions (?13C = ?13.2 to ?22.8‰, average = ?17.7‰) with obvious spatial variation. We provided a numerical modeling method to prove that the C isotopic composition of the Dalihu SiC can be well-yielded by degassing. Our modeling results showed that degassing reaction between graphite and silicate can readily produce the low ?13C value of SiC, and the spatial variations in C isotopic composition could have been formed in the progressive growth process of SiC. The detailed in situ occurring information is beneficial for our understanding of the preservation mechanism of the Dalihu ultra-reduced phase. The predominant occurrence of SiC in micro-cavities implies that exsolution and filling of CO2 and/or CO in the micro-cavities during the diapir rising process of carbonatitic melt could have buffered the reducing environment and separated SiC from the surrounding oxidizing phases. The fast cooling of host rock, which would leave insufficient time for the complete elimination of SiC, could have also contributed to the preservation of SiC.
DS201809-2063
2018
He, D.Liu, Y-S., Foley, S.F., Chien, C.F., He, D., Zong, K.Q.Mantle recycling of sedimentary carbonate along the northern margin of the North Chin a craton.Goldschmidt Conference, 1p. AbstractChinacarbonatite

Abstract: Sedimentary carbonate rocks, which exist extensively in the oceanic realm, are subducted to differing degrees during the closure of oceanic basins. However, very few observational data exist to provide details on the mechanisms of transport of carbonate materials from the surface to mantle depths and back to the Earth’s surface. Here we presented a series of diamond-bearing carbonatite xenoliths, carbonatite intrusions and carbonatite veins along the northern margin of the North China Craton (NCC). These carbonatites show geochemical features of recycled limestone (similar trace element patterns and high 87Sr/86Sr ratios of 0.705-0.709), indicating that they had a sedimentary limestone precursor. However, the presence of diamond, reduced minerals (e.g., moissanite), mantle-derived silicate minerals (eg., Cpx and Opx), and high Ni content and 143Nd/144Nd ratio indicate their staying for a time in the mantle. Combining with the zircon age spectrums of the carbonatite xenoliths and intrusions and the extensive high-87Sr/86Sr (up to 0.708) carbonatite metasomatism in the lithospheric mantle along the northern margin of NCC, we suggest that the limestone precursor could have been derived from the Paleo-Asian Ocean, and these carbonatites mark the subduction of a carbonate platform of the Paleo-Asian Oceanic slab to mantle depths beneath the NCC. Extensive mantle recycling of sedimentary carbonate could have contributed to the modification of the lithospheric mantle along the northern margin of the North China Craton.
DS1986-0350
1986
He, G.He, G., Shanguan, Z., Zhao, Y.Carbonatites and their patterns of rare earth elements (REE) distribution in Erdaobian and Boshanareas, ChinaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 39-41ChinaCarbonatite, rare earth elements (REE).
DS1986-0351
1986
He, G.He, G., Zhao, Y.Geochemistry of porphyritic kimberlites in Mengyin County,Shandong Province and in Fuxian County, Liaoning Province,ChinaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 36-38ChinaGeochemistry
DS201312-1010
2013
He, H.Zhang, D., Zhang, Z., Santosh, M., Cheng, Z., He, H., Kang, J.Perovskite and baddeleyite from kimberlitic intrusions in the Tarim large igneous province signal the onset of an end Carboniferous mantle plume.Earth and Planetary Science Letters, Vol. 361, pp. 238-248.ChinaDeposit - Wajiltag
DS201412-0966
2014
He, H.Wang, Y., He, H., Ivanov, A.V., Zhu, R.,Lo, C.Age and origin of charoitite, Malyy Murun massif, Siberia Russia.International Geology Review, Vol. 56, 8, pp. 1007-1019.RussiaCharoite
DS202004-0502
2020
He, H.Cawood, P.A., Wang, W., Zhao, T., Xu, Y., Mulder, J.A., Pisarevsky, S.A., Zhang, L., Gan, C., He, H., Liu, H., Qi, L., Wang, Y., Yao, J., Zhao, G., Zhou, M-F., Zi, J-W.Deconstructing south China and consequences for reconstructing Nuna and Rodinia.Earth-Science Reviews, in press available, 70p. PdfChinatectonics

Abstract: Contrasting models for internal and external locations of South China within the Nuna and Rodinia supercontinents can be resolved when the current lithotectonic associations of Mesoproterozoic and older rocks units that constitute the craton are redefined into four lithotectonic domains: Kongling, Kunming-Hainan, Wuyi, and Coastal. The Kongling and Kunming-Hainan domains are characterized by isolated Archean to early Paleoproterozoic rock units and events and crop out in northern and southern South China, respectively. The Kunming-Hainan Domain is preserved in three spatially separated regions at Kunming (southwestern South China), along the Ailaoshan shear zone, and within Hainan Island. Both domains were affected by late Paleoproterozoic tectonothermal events, indicating their likely juxtaposition by this time to form the proto-Yangtze Block. Late Paleoproterozoic and Mesoproterozoic sedimentary and igneous rock units developed on the proto-Yangtze Block, especially in its southern portions, and help link the rock units that formed along the shear zone at Ailaoshan and on Hainan Island into a single, spatially unified unit prior to Paleozoic to Cenozoic structural disaggregation and translation. The Wuyi Domain consists of late Paleoproterozoic rock units within a NE-SW trending, fault-bounded block in eastern South China. The Coastal Domain lies east of the Wuyi domain and is inferred to constitute a structurally separate block. Basement to the domain is not exposed, but zircon Hf model ages from Mesozoic granites suggest Mesoproterozoic basement at depth. The Archean to Paleoproterozoic tectonothermal record of the Kongling and Kunming-Hainan domains corresponds closely with that of NW Laurentia, suggesting all were linked, probably in association with assembly and subsequent partial fragmentation of the Nuna supercontinent. Furthermore, the age and character of Mesoproterozoic magmatism and detrital zircon signature of sedimentary rocks in the proto-Yangtze Block matches well with western Laurentia and eastern Australia-Antarctica. In particular, the detrital zircon signature of late Paleoproterozoic to early Mesoproterozoic sedimentary units in the block (e.g. Dongchuan Group) share a similar age spectrum with the Wernecke Supergroup of northwest Laurentia. This, together with similarities in the type and age of Fe-Cu mineralization in the domain with that in eastern Australia-Antarctica, especially northeast Australia, suggests a location adjacent to northwest Laurentia, southern Siberia, and northeast Australia within the Nuna supercontinent. The timing and character of late Paleoproterozoic magmatic activity in the Wuyi domain along with age of detrital zircons in associated sedimentary rocks matches the record of northern India. During rifting between Australia-Antarctica and Laurentia in the late Mesoproterozoic, the proto-Yangtze Block remained linked to northeast Australia. During accretionary orogenesis in the early Neoproterozoic, the proto-Yangtze Block assembled with the Wuyi Domain along the northern margin of India. The Coastal domain likely accreted at this time forming the South China Craton. Displacement of the Hainan and Ailaoshan assemblages from southwest of the Kunming assemblage likely occurred in the Cenozoic with the activation of the Ailaoshan-Red River fault system but could have begun in the early to mid-Paleozoic based on evidence for tectonothermal events in the Hainan assemblage.
DS202202-0219
2022
He, H.Tan, W., Qin, X., Liu, J., Zhou, M-F., He, H., Yang, C.Y., Huang, J., Zhu, J., Yao, Y., Cudahy, T.Feasibility of visible short-wave infrared reflectance spectroscopy to characterize regolith-hosted rare earth element mineralization.Economic Geology, Vol. 117, 3, pp. 485-494.Chinadeposit - Renju

Abstract: Regolith-hosted rare earth element (REE) deposits predominate global resources of heavy REEs. Regoliths are underlain by various types of igneous rocks and do not always host economically valuable deposits. Thus a feasible and convenient method is desired to identify REE mineralization in a particular regolith. This study presents a detailed visible short-wave infrared reflectance (VSWIR) spectroscopic study of the Renju regolith-hosted REE deposit, South China, to provide diagnostic parameters for targeting REE orebodies in regoliths. The results show that the spectral parameters, M794_2nd and M800_2nd, derived from the VSWIR absorption of Nd3+ at approximately 800 nm, can be effectively used to estimate the total REE concentrations in regolith profiles. M1396_2nd/M1910_2nd ratios can serve as proxies to evaluate weathering intensities in a regolith. Abrupt changes of specific spectral features related to mineral abundances, chemical compositions, and weathering intensities can be correlated with variations of protolith that formed a regolith. These VSWIR proxies are robust and can be used for exploration of regolith-hosted REE deposits.
DS200812-1235
2007
He, H-Y.Wang, F., Lu, X-X., Lo, C-H., Wu, F-Y., He, H-Y., Yang, L-K., Zhu, R-X.Post collisional, potassic monzonite-minette complex Shahewan in the Qinling Mountains: 40Ar 39Ar thermochronology, petrogenesis, implications - dynamicJournal of Asian Earth Sciences, Vol. 31, 2, October pp. 153-166.ChinaMinette
DS200412-0393
2004
He, J.Currie, C.A., Wang, K., Hyndman, R.D., He, J.The thermal effects of steady state slab driven mantle flow above a subducting plate: the Cascadia subduction zone and backarc.Earth and Planetary Science Letters, Vol. 223, 1-2, pp. 35-48.United States, WashingtonSubduction
DS200712-0161
2007
He, J.Chai, Y., Li, A., Shi, Y., He, J., Zhang, K.Kimberlites identification by classification methods.Lecture Notes in Computer Science, No. 4488, pp. 409-414.TechnologyClassification
DS200712-0162
2007
He, J.Chai, Y., Li, A., Shi, Y., He, J., Zhang, K.Kimberlites identification by classification methods.Lecture Notes in Computer Science, No. 4488, pp. 409-414.TechnologyClassification
DS200812-1223
2008
He, J.Wada, I., Wang, K., He, J., Hyndman, R.D.Weakening of the subduction surface abd its effects on surface heat flow, slab dehydration, and mantle wedge serpentinization.Journal of Geophysical Research, Vol. 113, B4, B04402MantleSubduction
DS200812-1224
2008
He, J.Wada, I., Wang, K., He, J., Hyndman, R.D.Weakening of the subduction interface and its effects on surface heat flow, slab dehydration, and mantle wedge serpentinization.Journal of Geophysical Research, Vol. 113, B04402.MantleSubduction, geothermometry
DS201412-0383
2014
He, J.Huang, Q., Yu, D., Xu, B., Hu, W., Ma, Y., Wang, Y., Zhao, Z., Wen, B., He, J., Liu, Z., Tian, Y.Nanotwinned diamond with unprecedented hardness and stability.Nature, Vol. 510, June 12, pp. 250-253.TechnologyDiamond synthetic
DS201012-0789
2010
He, K.Tkalcic, H., Cormier, V.F., Kennett, B.L.N., He, K.Steep reflections from the Earth's core reveal small scale heterogeneity in the upper mantle.Physics of the Earth and Planetary Interiors, Vol. 178, pp. 80-91.MantleGeoiphysics - seismics
DS2000-0423
2000
He, L.Hu, S., He, L., Wang, J.Heat flow in the continental area of China: a new dat a setEarth and Planetary Science Letters, Vol. 179, No. 2, June 30, pp. 407-ChinaGeothermometry, Heat flow
DS201502-0061
2015
He, L.He, L.Thermal regime of the North Chin a craton: implications for craton destruction.Earth Science Reviews, Vol. 140, pp. 14-26.ChinaGeothermometry
DS201809-2034
2018
He, L.He, L., Zhang, L.Thermal evolution of cratons in China. ReviewJournal of Asian Earth Sciences, Vol. 164, pp. 237-247.Chinageothermometry
DS2003-1511
2003
He, M.Xu, S., Liu, Y., Chen, G., Compagnoni, R., Rolfo, F., He, M., Liu, H.New finding of microdiamonds in eclogites from Dabie Sulu region in central easternChinese Science Bulletin, Science Press, Vol. 48, 10, May, pp. 988-994.ChinaUHP, Deposit - Dabie Shan area
DS200412-2159
2003
He, M.Xu, S., Liu, Y., Chen, G., Compagnoni, R., Rolfo, F., He, M., Liu, H.New finding of microdiamonds in eclogites from Dabie Sulu region in central eastern China.Chinese Science Bulletin, Vol. 48, 10, May, pp. 988-994.ChinaUHP Deposit - Dabie Shan area
DS202012-2240
2020
He, M.Pine, D., He, M.Researchers discover novel method for creating colloidal diamonds.Nature, www.sciencetimes.com/ articles/27434/ 20200924Globalnanodiamonds

Abstract: Colloidal diamonds - stable, self-assembled material with promising applications in light-related technologies - can now be fabricated, decades after its concept was first developed in the 90s.
DS202111-1788
2021
He, S.Sun, K., Zhao, Z., Zhang, L., Qiu, L., Liu, X., He, S., Ren, J., Ye, L., Cui, Y.Geochronology, petrography and Sr-Nd-Hf isotopes of Mbalizi carbonatite, southwestern Tanzania.Journal of African Sciences, Vol. 184, 104308, 12p. PdfAfrica, Tanzaniadeposit - Mbalizi

Abstract: The Mbalizi carbonatite is located in the middle of the Paleoproterozoic Ubendian Mobile Belt and the western branch of East Africa Rift, southwestern Tanzania. Calcite, dolomite, phlogopite, pyrochlore and apatite are found in the sample. Mineral chemistry studies have shown that the carbonatite phlogopite is linked to mantle-derived magmatism. The apatite is fluorapatite, means they are of magmatic origin. The analyses on two crystals of pyrochlore show high concentrations of Nb2O5, and therefore the Nb-oxide is classified as pyrochlore subspecies. Three types of zircon have been obtained from the Mbalizi carbonatite, including xenocrysts zircon, igneous zircon and metamorphic zircon. Zircon in-situ LA-ICP-MS U-Pb dating in this contribution indicates that the Mbalizi carbonatite was crystallized at ca. 116.0 ± 1.8 Ma. The ?Hf(t) values of igneous zircon ranging from ?13.9 to +5.7, indicates that the carbonatite parental magma was originated from the sub-continental lithospheric mantle, and evolves toward HIMU and EM. The whole-rock Sr-Nd isotopic data suggest more contribution of the HIMU and EM? material. We propose that the complex evolutionary history of the Ubendian Mobile Belt has stored the subduction oceanic crust which has the EM? and HIMU components, forming the compositional heterogeneity mantle beneath the Ubendian Mobile Belt. At 116.0 ± 1.8 Ma, with the extension stress field, deep faults cause the pressure reduction, resulting in reactive of the upwelling of the HIMU and EM? components. This provides the metamorphic conditions to induce the isotopic resetting and may result in large scatter of initial 176Hf/177Hf ratios of carbonatite melts.
DS201608-1450
2016
He, W-Y.Wang, R., Collins, W.J., Weinberg, R.F., Li, J-X., Li, Q-Y., He, W-Y., Richards, J.P., Hou, Z., Zhou, Li-M., Stern, R.A.Xenoliths in ultrapotassic volcanic rocks in the Lhasa block: direct evidence for crust mantle mixing and metamorphism in the deep crust.Contributions to Mineralogy and Petrology, in press available 19p.Asia, TibetMelting

Abstract: Felsic granulite xenoliths entrained in Miocene (~13 Ma) isotopically evolved, mantle-derived ultrapotassic volcanic (UPV) dykes in southern Tibet are refractory meta-granitoids with garnet and rutile in a near-anhydrous quartzo-feldspathic assemblage. High F-Ti (~4 wt.% TiO2 and ~3 wt.% F) phlogopite occurs as small inclusions in garnet, except for one sample where it occurs as flakes in a quartz-plagioclase-rich rock. High Si (~3.45) phengite is found as flakes in another xenolith sample. The refractory mineralogy suggests that the xenoliths underwent high-T and high-P metamorphism (800-850 °C, >15 kbar). Zircons show four main age groupings: 1.0-0.5 Ga, 50-45, 35-20, and 16-13 Ma. The oldest group is similar to common inherited zircons in the Gangdese belt, whereas the 50-45 Ma zircons match the crystallization age and juvenile character (?Hfi +0.5 to +6.5) of Eocene Gangdese arc magmas. Together these two age groups indicate that a component of the xenolith was sourced from Gangdese arc rocks. The 35-20 Ma Miocene ages are derived from zircons with similar Hf-O isotopic composition as the Eocene Gangdese magmatic zircons. They also have similar steep REE curves, suggesting they grew in the absence of garnet. These zircons mark a period of early Miocene remelting of the Eocene Gangdese arc. By contrast, the youngest zircons (13.0 ± 4.9 Ma, MSWD = 1.3) are not zoned, have much lower HREE contents than the previous group, and flat HREE patterns. They also have distinctive high Th/U ratios, high zircon ?18O (+8.73-8.97 ‰) values, and extremely low ?Hfi (?12.7 to ?9.4) values. Such evolved Hf-O isotopic compositions are similar to values of zircons from the UPV lavas that host the xenolith, and the flat REE pattern suggests that the 13 Ma zircons formed in equilibrium with garnet. Garnets from a strongly peraluminous meta-tonalite xenolith are weakly zoned or unzoned and fall into four groups, three of which are almandine-pyrope solid solutions and have low ?18O (+6 to 7.5 ‰), intermediate (?18O +8.5 to 9.0 ‰), and high ?18O (+11.0 to 12.0 ‰). The fourth is almost pure andradite with ?18O 10-12 ‰. Both the low and intermediate ?18O groups show significant variation in Fe content, whereas the two high ?18O groups are compositionally homogeneous. We interpret these features to indicate that the low and intermediate ?18O group garnets grew in separate fractionating magmas that were brought together through magma mixing, whereas the high ?18O groups formed under high-grade metamorphic conditions accompanied by metasomatic exchange. The garnets record complex, open-system magmatic and metamorphic processes in a single rock. Based on these features, we consider that ultrapotassic magmas interacted with juvenile 35-20 Ma crust after they intruded in the deep crust (>50 km) at ~13 Ma to form hybridized Miocene granitoid magmas, leaving a refractory residue. The ~13 Ma zircons retain the original, evolved isotopic character of the ultrapotassic magmas, and the garnets record successive stages of the melting and mixing process, along with subsequent high-grade metamorphism followed by low-temperature alteration and brecciation during entrainment and ascent in a late UPV dyke. This is an excellent example of in situ crust-mantle hybridization in the deep Tibetan crust.
DS2003-0604
2003
He, X.C.Hu, X.J., Dai, Y.B., Li, R.B., Shen, H.S., He, X.C.A molecular dynamics study of interstitial boron in diamondPhysica B, Vol. 327, 1, pp. 39-42.GlobalDiamond morphology
DS201508-0358
2015
He, X-F.He, X-F., Santosh, M., Zhang, Z-M., Tsunogae, T., Chetty, T.R.K., Ram Moham, M., AnbazhaganShonkinites from Salem, southern India: implications for Cryogenian alkaline magmatism in rift related setting.Journal of Asian Earth Sciences, in press availableIndiaShonkinites
DS201712-2727
2018
He, X-F.Santosh, M., Hari, K.R., He, X-F., Han, Y-S., Manu Prasanth, M.P.Oldest lamproites from Peninsular India track the onset of Paleoproterozoic plume induced rifting and the birth of Large Igneous Province.Gondwana Research, Vol. 55, pp. 1-20.Indialamproites - Nuapada

Abstract: Potassic and ultrapotassic magmatism from deep lithospheric sources in intra-cratonic settings can be the signal of subsequent voluminous mafic magmatism and the formation of Large Igneous Provinces (LIPs) triggered by mantle plumes. Here we report for the first time, precise zircon U-Pb age data from a suite of lamproites in the Bastar Craton of central India that mark the onset of Paleoproterozoic rifting and culminating in the formation of extensive mafic dyke swarms as the bar codes of one of the major LIP events during the Precambrian evolution of the Indian shield. The lamproites from the Nuapada field occur as dismembered dykes and are composed of phenocrysts and microphenocrysts of altered olivine together with microphenocrysts of phlogopite and magnetite within a groundmass of chlorite and calcite with accessory rutile, apatite and zircon. The rocks compositionally correspond to olivine phlogopite lamproite and phlogopite lamproite. Geochemical features of the lamproites correlate with their counterparts in Peninsular India and other similar suites elsewhere in the world related to rift settings, and also indicate OIB-like magma source. The associated syenite shows subduction-related features, possibly generated in a post-collisional setting. Magmatic zircon grains with high Th/U ratios in the syenite from the Nuapada lamproite form a coherent group with an upper intercept age of 2473 ± 8 Ma representing the timing of emplacement of the magma. Zircon grains in three lamproite samples yield four distinct age groups at ca. 2.4 Ga, 2.2 Ga, 2.0 Ga and 0.8 Ga. The 2.4 Ga group corresponds to xenocrysts entrained from the syenite whereas the 2.2 Ga group is considered to represent the timing of emplacement of the lamproites. The ca. 2.0 Ga zircon grains correlate with the major thermal imprint associated with mafic magmatism and dyke emplacement in southern Bastar and the adjacent Dharwar Cratons. A few young zircon grains in the syenite and lamproites show a range of early to middle Neoproterozoic ages from 879 to 651 Ma corresponding to younger thermal event(s) as also represented by granitic veins cutting across these rocks and extensive silicification. Zircon Lu-Hf isotope data suggest magma derivation from a refertilized Paleo-Mesoarchean sub-continental lithospheric mantle, or OIB-type sources. The differences in Hf-isotope composition among the zircon grains from different age groups indicate that the mantle sources of the lamproite are heterogeneous at the regional scale. A combination of the features from geochemical and zircon Hf isotope data is consistent with asthenosphere-lithosphere interaction during the lamproite magma evolution. The timing of lamproite emplacement in central India correlates with the global 2.2 Ga record of LIPs. We link the origin of the related mantle plume to the recycling of subducted slabs associated with the prolonged subduction-accretion history prior to the Neoarchean cratonization, as well as the thermal blanket effect of the Earth’s oldest supercontinent. Pulsating plumes and continued rifting generated voluminous dyke swarms across the Bastar and Dharwar Cratons, forming part of a major global rifting and LIP event.
DS201802-0262
2018
He, X-F.Santosh, M., Hari, K.R., He, X-F., Han, Y-S., Manu Prasanth, M.P.Oldest lamproites from Peninsular India track the onset of Paleoproterozoic plume induced rifting and the birth of Large Igneous Province.Gondwana Research, Vol. 55, pp. 1-20.Indialamproites

Abstract: Potassic and ultrapotassic magmatism from deep lithospheric sources in intra-cratonic settings can be the signal of subsequent voluminous mafic magmatism and the formation of Large Igneous Provinces (LIPs) triggered by mantle plumes. Here we report for the first time, precise zircon U-Pb age data from a suite of lamproites in the Bastar Craton of central India that mark the onset of Paleoproterozoic rifting and culminating in the formation of extensive mafic dyke swarms as the bar codes of one of the major LIP events during the Precambrian evolution of the Indian shield. The lamproites from the Nuapada field occur as dismembered dykes and are composed of phenocrysts and microphenocrysts of altered olivine together with microphenocrysts of phlogopite and magnetite within a groundmass of chlorite and calcite with accessory rutile, apatite and zircon. The rocks compositionally correspond to olivine phlogopite lamproite and phlogopite lamproite. Geochemical features of the lamproites correlate with their counterparts in Peninsular India and other similar suites elsewhere in the world related to rift settings, and also indicate OIB-like magma source. The associated syenite shows subduction-related features, possibly generated in a post-collisional setting. Magmatic zircon grains with high Th/U ratios in the syenite from the Nuapada lamproite form a coherent group with an upper intercept age of 2473 ± 8 Ma representing the timing of emplacement of the magma. Zircon grains in three lamproite samples yield four distinct age groups at ca. 2.4 Ga, 2.2 Ga, 2.0 Ga and 0.8 Ga. The 2.4 Ga group corresponds to xenocrysts entrained from the syenite whereas the 2.2 Ga group is considered to represent the timing of emplacement of the lamproites. The ca. 2.0 Ga zircon grains correlate with the major thermal imprint associated with mafic magmatism and dyke emplacement in southern Bastar and the adjacent Dharwar Cratons. A few young zircon grains in the syenite and lamproites show a range of early to middle Neoproterozoic ages from 879 to 651 Ma corresponding to younger thermal event(s) as also represented by granitic veins cutting across these rocks and extensive silicification. Zircon Lu-Hf isotope data suggest magma derivation from a refertilized Paleo-Mesoarchean sub-continental lithospheric mantle, or OIB-type sources. The differences in Hf-isotope composition among the zircon grains from different age groups indicate that the mantle sources of the lamproite are heterogeneous at the regional scale. A combination of the features from geochemical and zircon Hf isotope data is consistent with asthenosphere-lithosphere interaction during the lamproite magma evolution. The timing of lamproite emplacement in central India correlates with the global 2.2 Ga record of LIPs. We link the origin of the related mantle plume to the recycling of subducted slabs associated with the prolonged subduction-accretion history prior to the Neoarchean cratonization, as well as the thermal blanket effect of the Earth's oldest supercontinent. Pulsating plumes and continued rifting generated voluminous dyke swarms across the Bastar and Dharwar Cratons, forming part of a major global rifting and LIP event.
DS2003-0004
2003
He, Y.Ai, Y., Zheng, T., Xu, W., He, Y., Dong, D.A complex 660 km discontinuity beneath northeast ChinaEarth and Planetary Science Letters, Vol. 212, 1-2, pp. 63-71.ChinaTectonics
DS200412-0009
2003
He, Y.Ai, Y., Zheng, T., Xu, W., He, Y., Dong, D.A complex 660 km discontinuity beneath northeast China.Earth and Planetary Science Letters, Vol. 212, 1-2, pp. 63-71.ChinaGeophysics - seismics Tectonics
DS200612-1509
2006
He, Y.Wang, Yi., Wen, L., WEidner, D., He, Y.SH velocity and compositional models near the 660 km discontinuity beneath South America and northeast Asia.Journal of Geophysical Research, Vol. 111, B7 B07305.South America, AsiaGeophysics - seismics
DS200812-0488
2008
He, Y.Huang, F., li, S., Dong, F., He, Y., Chen, F.High mag adakitic rocks in the Dabie orogen, central China: implications for foundering mechanisms of lower continental crust.Chemical Geology, Vol. 255, 1-2, Sept. 30, pp. 1-13.ChinaUHP
DS200812-1248
2008
He, Y.Wen, L., He, Y.Pacific and African anomalies. Earth's early differentiation, mantle dynamics and geochemistry.Goldschmidt Conference 2008, Abstract p.A1015.MantleStructural features
DS202203-0350
2022
He, Y.He, Y., Sun, S., Kim, D.Y., Jang, B.G., Li, H., Mao, H-K.Superionic iron alloys and their seismic velocities in Earth's inner core.Nature, Vol. 602, pp. 258-276. 18p.Mantlecore

Abstract: Earth’s inner core (IC) is less dense than pure iron, indicating the existence of light elements within it1. Silicon, sulfur, carbon, oxygen and hydrogen have been suggested to be the candidates2,3, and the properties of iron-light-element alloys have been studied to constrain the IC composition4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19. Light elements have a substantial influence on the seismic velocities4,5,6,7,8,9,10,11,12,13, the melting temperatures14,15,16,17 and the thermal conductivities18,19 of iron alloys. However, the state of the light elements in the IC is rarely considered. Here, using ab initio molecular dynamics simulations, we find that hydrogen, oxygen and carbon in hexagonal close-packed iron transform to a superionic state under the IC conditions, showing high diffusion coefficients like a liquid. This suggests that the IC can be in a superionic state rather than a normal solid state. The liquid-like light elements lead to a substantial reduction in the seismic velocities, which approach the seismological observations of the IC20,21. The substantial decrease in shear-wave velocity provides an explanation for the soft IC21. In addition, the light-element convection has a potential influence on the IC seismological structure and magnetic field.
DS2003-0208
2003
He, Z.Cao, J., He, Z., Zhu, J., Fullagar, P.K.Conductivity tomography at two frequenciesGeophysics, Vol. 68, 2, pp. 516-22.MantleGeophysics - seismics
DS200412-0269
2003
He, Z.Cao, J., He, Z., Zhu, J., Fullagar, P.K.Conductivity tomography at two frequencies.Geophysics, Vol. 68, 2, pp. 516-22.MantleGeophysics - seismics
DS1980-0167
1980
He Guan ZhiHe Guan ZhiOn the Genetic Mechanism of Kimberlite and DiamondGeological Review., Vol. 26, No. 5, PP. 384-392.ChinaKimberlite, Genesis
DS1984-0350
1984
He Guan ZhiHe Guan ZhiKimberlites in Chin a and Their Major Components: a Discussion on the Physico Chemical Properties of the Upper Mantle.Proceedings of Third International Kimberlite Conference, KORNPROBST, J. EDITOR: DEVELOPMENTS IN PE, Vol. 1, PP. 181-194.China, Shandong, Liaoning, GiuzhouKimberlite Mineralogy, Petrology, Age Dating, Structure, Textur
DS1960-0556
1965
He Guan-ZheHe Guan-ZheThe Microstructure of the Surface of Several Types of DiamonScientia Geol. Sinica., Vol. 1, No. 1, PP. 69-76.ChinaMicrodiamonds, Crystallography
DS1987-0284
1987
He Guan-ZhiHe Guan-ZhiMantle xenoliths from kimberlites in Chinain: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 181-186Chinap. 184 Analyses pyropes and philogopite from kimberlit
DS1987-0285
1987
He Xiong, D.A.He Xiong, D.A., Mahoney, J.J.Preliminary experimental study of the relationship between kimberlite and metasomatism of duniteEos, abstractGlobalMantle genesis
DS1992-0948
1992
He YongnianLin Chuanyong, Shi Lanbin, He Yongnian, Chen XiaodePhysical state and rheology of the upper mantle beneath eastern China:evidence from mantle xenolithsInternational Symposium Cenozoic Volcanic Rocks Deep seated xenoliths China and its, Abstracts pp. 71-74ChinaMantle, Xenoliths
DS200412-0477
2004
HeaDownes, H., Macdonald, R., Upton, B.G.J., Cox, K.G., Bodinier, J-L., Mason, P.R.D., James, D., Hill, P.G., HeaUltramafic xenoliths from the Bearpaw Mountains, Montana: USA: evidence for multiple metasomatic events in the lithospheric mantJournal of Petrology, Vol. 45, 8, pp. 1631-1662.United States, MontanaMetasomatism
DS1995-0507
1995
Head, J.W.Ernst, R.E., Head, J.W., Parfitt, Grosfils, WilsonGiant radiating dyke swarms on Earth and VenusEarth Science Reviews, Vol. 39, No. 1-2, Sept. pp. 1-58.GlobalDyke swarms, Review
DS1995-0510
1995
Head, J.W.Ernst, R.E., Head, J.W., Parfitt, E., Grosfils, E., WilsonGiant radiating dyke swarms on Earth and VenusEarth Science Reviews, Vol. 39 No. 1-2, Sept. pp. 1-58GlobalDike swarms, Review
DS2003-0567
2003
Head, J.W.Head, J.W., Wilson, L.Diatremes and kimberlites 1.: definition, geological characteristics and associations8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractGlobalGeology, economics, Magmatism - model stages
DS2003-1486
2003
Head, J.W.Wilson, L., Head, J.W.Diatremes and kimberlites 2.: an integrated model of the ascent and eruption of8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractGlobalGeology, economics, Magmatism - carbon dioxide CO2
DS200412-0809
2003
Head, J.W.Head, J.W., Wilson, L.Diatremes and kimberlites 1.: definition, geological characteristics and associations.8 IKC Program, Session 1, AbstractTechnologyGeology, economics Magmatism - model stages
DS200412-2130
2003
Head, J.W.Wilson, L., Head, J.W.Diatremes and kimberlites 2.: an integrated model of the ascent and eruption of kimberlitic magmas and the production of crater,8 IKC Program, Session 1, AbstractTechnologyGeology, economics Magmatism - carbon dioxide CO2
DS201412-0349
2014
Heads, H.Heads, H.How far can the influence of a local marine Diamondiferous signature be traced through an aeolian depositional system?GSSA Kimberley Diamond Symposium and Trade Show provisional programme, Sept. 10-12, POSTERAfrica, NamibiaSedimentology
DS1994-1617
1994
Heagy, A.E.Sinclair, W.D., Richardson, J.M., Heagy, A.E., Garson, D.Mineral deposits of Canada -preliminary map and deposit listGeological Survey of Canada Open file, No. 2874, 34p. 1 disk. total cost $ 47.30CanadaMineral deposit listing, Map
DS201412-0184
2014
Heagy, L.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794 extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho
DS201412-0250
2014
Heagy, L.Fournier, D., Heagy, L., Corcoran, N., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1798. Extended abstractCanada, Northwest TerritoriesGeophysics - Tli Kwi Cho complex
DS201501-0006
2014
Heagy, L.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO-18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201501-0009
2014
Heagy, L.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS201611-2103
2014
Heagy, L.Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne dat a sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, pp. 1790-1794. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO- 18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS201611-2106
2016
Heagy, L.Fournier, D., Heagy, L.Where are the diamonds? - using Earth's potentialsSimPEG Team, 1p. Poster pdfTechnologyGeophysics - Magnetics, gravity
DS201611-2107
2014
Heagy, L.Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Marchant, M., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, pp. 1795-1799. pdfCanada, Northwest TerritoriesDeposit - Tli Kwi Cho

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS1992-0687
1992
Healey, C.M.Healey, C.M.Geology as a risk factor in project evaluation: its impact on reserveestimationThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Exploration and Mining Geology, Vol. 1, No. 3, July pp. 243-250SaskatchewanGeostatistics, ore reserves, Deposits -Star Lake, Laurel Lake
DS200712-0167
2007
Healy, D.Chappell, A., Eccles, J., Fletcher, R., Healy, D.Imaging the pulsing Iceland mantle plume through the Eocene.Geology, Vol. 35, 1, pp. 93-96.Europe, IcelandGeophysics - seismics
DS201112-0191
2011
Healy, D.Clark, C., Fitzsimons, I.C.W., Healy, D., Harkley, S.L.How does the continental crust get really hot?Elements, Vol. 7, 4, August pp. 235-240.MantleMetamorphism, UHT, thermal modelling
DS201112-1048
2011
Healy, D.Timms, N.E., Kinny, P.D., Reddy, S.M., Evans, K., Clark, C., Healy, D.Relationship among titanium, rare earth elements, U-Pb ages and deformation microstructures in zircon: implications for Ti in zircon thermometry.Chemical Geology, Vol. 280, 1-2, pp. 33-46.Russia, SiberiaXenoliths
DS1983-0256
1983
Healy, J.Ginzburg, A., Mooney, W.D., Walter, A.W., Lutter, W.J., Healy, J.Deep Structure of Northern Mississippi EmbaymentAmerican Association of Petroleum Geologists Bulletin., Vol. 67, No. 11, NOVEMBER PP. 2031-3046.GlobalMid Continent
DS1981-0274
1981
Healy, J.H.Lutter, W., Peters, D., Mooney, W.D., Healy, J.H.Crustal Structure of the Mississippi Embayment; Axial ProfilEos, Vol. 62, No. 45, P. 1046. (abstract.).GlobalMid-continent
DS1987-0379
1987
HeamanKrogh, T.E., Corfu, F., Davis, Dunning, Heaman, NakamuraPrecise uranium-lead (U-Pb) isotopic ages of diabase dikes and mafic to ultramafic rocks using trace amounts of baddeleyiteHalls and Fahrig, Geological Association of Canada (GAC) Special Vol., No. 34, pp. 147-52.Quebec, Ontario, Manitoba, Northwest TerritoriesGeochronology
DS1991-1481
1991
HeamanRyan, B., Krogh, T.E., Heaman, Scharer, PhillipeOn recent geochronological studies in the Nain Province Churchill province and Plutonic Suite.Newfound. Geological Survey, Paper 91-1, pp. 257-61.Quebec, Labrador, UngavaNain Plutonic suite, Geochronology
DS2001-0610
2001
HeamanKjarsgaard, B.A., Leckie, McNeil, Heaman, McIntyreCretaceous kimberlite chaos? Fort a la Corne revisited, reworked and resolvedSaskatchewan Open House abstracts, Nov. p. 27-8.SaskatchewanGeochronology, Deposit - Fort a la Corne
DS2002-1037
2002
HeamanMcNeil, D.H., Zonnenveld, J.P., Kjarsgaard, HeamanInitial results towards a biostratigraphic chronostratigraphic framework for Albian Cenomanian...Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.75., p.75.SaskatchewanStrata - eruptive events
DS2002-1038
2002
HeamanMcNeil, D.H., Zonnenveld, J.P., Kjarsgaard, HeamanInitial results towards a biostratigraphic chronostratigraphic framework for Albian Cenomanian...Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.75., p.75.SaskatchewanStrata - eruptive events
DS1987-0430
1987
Heaman, L.Machado, N., Heaman, L.Isotope geochemistry of the Coldwell alkaline complex II evidence for crustal contamination from preliminary Sr and neodymium dat a on primary mineralsGeological Association of Canada (GAC), Vol.12, p. 69. abstractOntarioGeochronology, Isotope
DS1991-0690
1991
Heaman, L.Heaman, L., Ludden, J.N.Application of radiogenic isotope systems to problems in geologyMineralogical Association of Canada, Vol. 19, 430pGlobalBook -table of contents, Geochronology, isotopes
DS1991-0691
1991
Heaman, L.Heaman, L., Ludden, J.N.Applications of radiogenic isotope systems to problems in geologyMineralogical Association of Canada -Short Course Handbook, Vol. 19, 425pGlobalGeochronology, Radiogenic
DS1991-0692
1991
Heaman, L.Heaman, L., Parrish, R.uranium-lead (U-Pb) (U-Pb) geochronology of accessory mineralsMineralogical Association of Canada -Short Course Handbook, Vol. 19, Chapter 3, pp. 59-100GlobalGeochronology, Accessory minerals
DS1998-0599
1998
Heaman, L.Heaman, L., Teixeira, N.A., Gobbo, L., Gaspar, J.C.uranium-lead (U-Pb) mantle zircon ages for kimberlites from the Juin a and ParanatingaProvinces, Brasil.7th International Kimberlite Conference Abstract, pp. 322-4.BrazilGeochronology, Deposit - Juina
DS1998-1110
1998
Heaman, L.Pan, Y., Fleet, M.E., Heaman, L.Thermo-tectonic evolution of an Archean accretionary complex: uranium-lead (U-Pb) (U-Pb)geochronological constraintsgranulitesPrecambrian Research, Vol. 92, No. 2, Oct.l, pp. 117-28OntarioGeochronology, Quetico Subprovince
DS2002-1246
2002
Heaman, L.Percival, J.A., Brown, M., Heaman, L., Hynes, A., Rivers, T., Skulski, T.Tectonic and magmatic processes in crustal growth: a pan lithospheric perspectiveGeoscience Canada, Vol. 29, 7, Sept. pp. 121-5.MantleMafic magmatism, accretionary tectonics, collision
DS2002-1247
2002
Heaman, L.Percival, J.A., Brown, M., Heaman, L., Rivers, T., Skulski, T.Tectonic and magmatic processes in crustal growth: a pan-lithoprobe perspectiveGeoscience Canada, Vo. 29, No. 3, September pp. 121-5.Canada, MantleGeophysics - seismics, lithoprobe, rifting, arc, Accretion, collision
DS2003-0723
2003
Heaman, L.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.Mineralogy of the kimberlite boulders from eskers in the Kirkland Lake and Lake8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractOntarioGeochemistry, geomorphology
DS2003-0972
2003
Heaman, L.Moorhead, J., Beaumier, M., Girard, R., Heaman, L.Distribution, structural controls and ages of kimberlite fields in the Superior Province of8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractQuebecGeochronology, tectonics
DS200412-1012
2003
Heaman, L.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.Mineralogy of the kimberlite boulders from eskers in the Kirkland Lake and Lake Timiskaming areas, northeastern Ontario, Canada.8 IKC Program, Session 8, POSTER abstractCanada, OntarioDiamond exploration Geochemistry, geomorphology
DS200412-1362
2003
Heaman, L.Moorhead, J., Beaumier, M., Girard, R., Heaman, L.Distribution, structural controls and ages of kimberlite fields in the Superior Province of Quebec.8 IKC Program, Session 8, POSTER abstractCanada, QuebecDiamond exploration Geochronology, tectonics
DS200512-0402
2005
Heaman, L.Harper, C.T., Van Breeman, O., Wodick,N., Pehrsson, S., Heaman, L., Hartlaub, R.The Paleoproterozoic lithostructural history and thermotectonic reactivation of the Archean basement in southern Hearne domain of northeastern Saskatchewan.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, SaskatchewanTrans Hudson orogen
DS200512-0579
2004
Heaman, L.Krauss, C., Chacko, T., Heaman, L., Whiteford, S.Lower crustal xenoliths from the Diavik mine - a preliminary examination of pressure - temperature conditions.32nd Yellowknife Geoscience Forum, Nov. 16-18, p.44. (poster)Canada, Northwest TerritoriesGeochronology
DS200512-0828
2004
Heaman, L.Patterson, M.,Heaman, L.The origin of diabase dykes in the Lac du Sauvage - Lac de Gras area, NWT.32nd Yellowknife Geoscience Forum, Nov. 16-18, p.58. (poster)Canada, Northwest TerritoriesMafic magmatism
DS200912-0384
2009
Heaman, L.Kjarsgaard, B.A., Harvey, S., McClintock, M., Zonneveld, J.P., Du Plessis, P., McNeil, D., Heaman, L.Geology of the Orion South kimberlite, Fort a la Corne, Canada.Lithos, In press - available formatted 15p.Canada, SaskatchewanDeposit - Orion South
DS201012-0025
2010
Heaman, L.Aulbach, S., Stachel, T., Heaman, L., creaser, R., Shirey, S.Formation of cratonic subcontinental lithospheric mantle from hybrid plume sources.Goldschmidt 2010 abstracts, abstractMantleSubduction
DS201012-0720
2010
Heaman, L.Smart, K., Chacko, T., Heaman, L., Stachel, T., Muehlenbachs, K.13 C depleted diamonds in Jericho eclogites: diamond formation from ancient subducted organic matter.Goldschmidt 2010 abstracts, abstractCanada, NunavutDeposit - Jericho
DS201012-0779
2010
Heaman, L.Tappe, S., Pearson, D.G., Heaman, L., Nowell, G., Milstead, P.Relative roles of cratonic lithosphere and asthenosphere in controlling kimberlitic magma compositions: Sr Nd Hf isotope evidence fromGoldschmidt 2010 abstracts, abstractEurope, Greenland, Canada, LabradorGeochronology
DS201112-0281
2010
Heaman, L.Donatti Filho, J.P., Paiva de Oliveira, E., Tappeb, S., Heaman, L.U Pb TIMS perovskite dating of the Brauna kimberlite field, Sao Francisco craton - Brazil: constraints on Neoproterozoic alkaline magmatism.5th Brasilian Symposium on Diamond Geology, Nov. 6-12, abstract p. 81.South America, BrazilGeochronology
DS201312-0777
2013
Heaman, L.Sarkar, C., Heaman, L., Pearson, D.G.Detailed geochemical studies of Lac de Gras kimberlites - redefining the 'diamond age window'?Geoscience Forum 40 NWT, abstract only p. 43Canada, Northwest TerritoriesDeposit - Lac de gras ones
DS201412-0685
2014
Heaman, L.Petts, D., Stern, R., Stachel, T., Chacko, T., Heaman, L.A nitrogen isotope fractionation factor between diamond and fluid derived from detailed SIMS analysis of an eclogitic diamond.Goldschmidt Conference 2014, 1p. AbstractTechnologyGeochronology
DS201708-1667
2017
Heaman, L.Heaman, L.Ages and sources of mantle eclogites: ID-TIMS-U-Pb-Sr isotope systematics of clinopyroxene.11th. International Kimberlite Conference, PosterMantleeclogite
DS201904-0787
2019
Heaman, L.Tappert, R., Foden, J., Heaman, L., Tappert, M.C., Zurevinski, S.E., Wills, K.The petrology of kimberlites from South Australia: linking olivine macrocrystic and micaceous kimberlites.Journal of Volacnology and Geothermal Research, Vol. 373, pp. 68-96.Australia, South Australiadeposit - Eurelia

Abstract: Kimberlites of Jurassic age occur in various parts of South Australia. Thirty-nine of these kimberlites, which are mostly new discoveries, were studied to characterize their structural setting, their petrography, and the composition of their constituent minerals. Although some of the kimberlites in South Australia occur on the Archean to Paleoproterozoic Gawler Block, most are part of a northwest-trending, semi-continuous kimberlite dike swarm located in the Adelaide Fold Belt. The kimberlites typically occur as dikes or sills, but diatremes are also present. In the Adelaide Fold Belt, diatremes are restricted to the hinge zones of regional-scale folds within thick sedimentary sequences of the Adelaidean Supergroup. Despite widespread and severe alteration, coherent and pyroclastic kimberlites can be readily distinguished. U-Pb and Sr/Nd isotopic compositions of groundmass perovskite indicate that all kimberlites belong to the same age group (177-197?Ma) and formed in a near-primitive mantle environment (87Sr/86Sr: 0.7038-0.7052, ?Nd: ?0.07 to +2.97). However, the kimberlites in South Australia are compositionally diverse, and range from olivine-dominated varieties (macrocrystic kimberlites) to olivine-poor, phlogopite-dominated varieties (micaceous kimberlites). Macrocrystic kimberlites contain magnesium-rich groundmass phlogopite and spinel, and they are typically olivine macrocryst-rich. Micaceous kimberlites, in contrast, contain more iron- and titanium-rich groundmass phlogopite and less magnesian spinel, and olivine macrocrysts are rare or absent. Correlations between phlogopite and spinel compositions with modal abundances of olivine, indicate that the contrast between macrocrystic and micaceous kimberlites is primarily linked to the amount of mantle components that were incorporated into a compositionally uniform parental mafic silicate melt. We propose that assimilation of xenocrystic magnesite and incorporation of xenocrystic olivine from dunitic source rocks were the key processes that modified the parental silicate melt and created the unique hybrid (carbonate-silicate) character of kimberlites. Based on the composition of xenoliths and xenocrysts, the lithospheric mantle sampled by the South Australian kimberlites is relatively uniform, and extends to depths of 160-170?km, which is slightly below the diamond stability field. Only beneath the Eurelia area does the lithosphere appear thicker (>175?km), which is consistent with the presence of diamonds in some of the Eurelia kimberlites.
DS202008-1398
2020
Heaman, L.Greene, S., Jacob, D.E., O'Reilly, S.Y., Henry, H., Pinter, Z., Heaman, L.Extensive prekimberlitic lithosphere modification recorded in Jericho mantle xenoliths in kimberlites, Slave Craton.Goldschmidt 2020, 1p. AbstractCanada, Northwest Territoriesdeposit - Jericho

Abstract: Wehrlite and pyroxenite xenoliths and megacrysts from the Jericho kimberlite were analyzed by ?XRF and EBSD, and for major elements, trace elements, and isotopes (Pb-Sr- O) in major phases. Thermobarometry places these samples at 60 - 180 km and 600 - 1200 ??C. While modes and textures vary, many samples have olivine-olivine grain boundaries with straight edges and 120° angle junctions, indicating granoblastic recrystallisation, while clinopyroxene and orthopyroxene are complexly intergrown. Clinopyroxene twins and subgrains recording orientations distinct from the encapsulating grain were detected using EBSD and are inferred to represent recent modification processes. Several distinct garnet compositions were measured, with multiple thin garnet rims in some samples suggesting possible successive stages of garnet crystallisation. Complex chromium zoning in garnet is detected by ?XRF in several samples (fig.1). Pb-Pb ages for most samples are similar to the age of kimberlite entrainment (173 Ma), but the shallowest pyroxenite sample preserves the most radiogenic Pb composition, intercecting concordia at 0.7 - 1.1 Ga, and is the only sample with ?18O above the mantle range (6.2±0.1 ‰). The deepest sample has the lowest ?18O (5.5±0.1 ‰) and radiogenic 87Sr/86Sr similar to MARID rocks (0.709±1 ‰). These results suggest the Jericho lithosphere experienced several melt/fluid injection events that modified substantial portions of the sampled section soon before kimberlite entrainment.
DS201112-0044
2011
Heaman, L.H.Aulbach, S., Stachel, T., Heaman, L.H., Carlson, J.A.Microxenoliths from the Slave Craton: archives of diamond formation along fluid conduits.Lithos, Vol. 126, pp. 419-434.Canada, Northwest TerritoriesEclogite, subduction, metasomatism, Ekati
DS201912-2789
2019
Heaman, L.H.Heaman, L.H., Phillips, D., Pearson, D.G.Dating kimberlite: methods and emplacement patterns through time.Elements, Vol. 15, 6, pp.Mantlegeochronology
DS1986-0352
1986
Heaman, L.M.Heaman, L.M., et al.Precise uranium-lead (U-Pb) zircon ages for the Molson dike swarm and the Fox River sill:constraints for Early ProterozoicContributions to Mineralogy and Petrology, Vol. 94, pp. 82-89.ManitobaGeochronology, Dike - Molson
DS1987-0378
1987
Heaman, L.M.Krogh, T.E., Corfu, F., Davis, D.W., Dunning, G.R., Heaman, L.M.Precise uranium-lead (U-Pb) (U-Pb) ages of diabase dykes and mafic to ultramafic rocks usingGeological Association of Canada (GAC) Special Paper, No. 34, p. 151QuebecIle Bizard kimberlite brief mention
DS1989-0603
1989
Heaman, L.M.Heaman, L.M.uranium-lead (U-Pb) (U-Pb) dating of mafic dyke swarms: what are the options?New Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 125 Abstract held June 25-July 1GlobalGeochronology, Dykes
DS1989-0604
1989
Heaman, L.M.Heaman, L.M.The nature of the subcontinental mantle from Sr-Neodymium-Palladium isotopic studies onkimberlitic perovskiteEarth and Planetary Science Letters, Vol. 92, pp. 323-334Ontario, Kirkland LakeMantle, Geochronology-isotopes
DS1989-0605
1989
Heaman, L.M.Heaman, L.M.An example of anomalous uranium-lead (U-Pb) (U-Pb) discordance patterns inbaddeleyitefrom the Ile Bizard intrusion MontrealGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A71. (abstract.)QuebecGeochronology
DS1989-0606
1989
Heaman, L.M.Heaman, L.M., Tarney, J.uranium-lead (U-Pb) (U-Pb) baddeleyite ages for the Scourie dyke swarm,Scotland: evidence for two distinct intrusion eventsNature, Vol. 340, August 31, pp. 705-708ScotlandDyke, Age determination -picrit
DS1989-0742
1989
Heaman, L.M.Kamo, S.L., Heaman, L.M., Lumbers, S.B.Age for a lamprophyre dyke, Callander Bay, Ontario:use of Ti bearing minerals as a potentialgeochronometerGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A41. (abstract.)OntarioGeochronology
DS1989-0866
1989
Heaman, L.M.LeCheminant, A.N., Heaman, L.M.Hotspot origin for giant radiating dyke swarms:evidence from the Mackenzie igneous events, CanadaNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 160. AbstractNorthwest TerritoriesDykes
DS1989-0867
1989
Heaman, L.M.LeCheminant, A.N., Heaman, L.M.Mackenzie igneous events, Canada: Middle Proterozoic hotspot magmatism associated with ocean openingEarth and Planetary Science Letters, Vol. 96, pp. 38-48Northwest Territories, SaskatchewanDykes, Geochronology
DS1990-0365
1990
Heaman, L.M.Corriveau, L., Heaman, L.M., Marcantonio, F., Vanbreemen, O.1.1 GA potassium-rich alkaline plutonism in the southwest Grenville province-Contributions to Mineralogy and Petrology, Vol. 105, No. 4, pp. 473-485OntarioAlkaline rocks, Geochronology
DS1990-0681
1990
Heaman, L.M.Heaman, L.M., Bowins, R., Crocket, J.The chemical composition of igneous zircon suites: implications for geochemical tracer studiesGeochimica et Cosmochimica Acta, Vol. 54, pp. 1597-1607South Africa, OntarioKimberlites, Carbonatite, Geochemistry -zircon
DS1991-0968
1991
Heaman, L.M.LeCheminant, A.N., Heaman, L.M.uranium-lead (U-Pb) (U-Pb) ages for the 1.27 Ga Mackenzie igneous events, Canada: support for aplume initiation modelGeological Association of Canada (GAC)/Mineralogical Association of Canada/Society Economic, Vol. 16, Abstract program p. A73Northwest TerritoriesGeochronology, Dykes
DS1991-1197
1991
Heaman, L.M.Moser, D.E., Krogh, T.E., Heaman, L.M., Hanes, J.A., Helmstaedt, H.The age and significance of Archean mid-crustal extension in the Kapuskasing uplift, Superior Province, CanadaGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 134OntarioTectonics, Kapuskasing uplift
DS1991-1305
1991
Heaman, L.M.Patterson, J.G., Heaman, L.M.New geochronologic limits on the depositional age of the Hurwitz Group, Trans-Hudson hinterland, CanadaGeology, Vol. 19, No. 11, November pp. 1137-1140Northwest TerritoriesGeochronology, Structure
DS1992-0596
1992
Heaman, L.M.Gower, C.F., Sharer, U., Heaman, L.M.The Labradorian Orogeny in the Grenville Province, eastern Labrador, Canada.Canadian Journal of Earth Sciences, Vol. 29, pp. 1944-57.Quebec, Labrador, UngavaOrogeny, Tectonics
DS1992-0688
1992
Heaman, L.M.Heaman, L.M., LeCheminant, A.N.uranium-lead (U-Pb) (U-Pb) systematics of mantle derived zircon and baddeleyite xenocrysts:implications for excess 208Pb in the mantleV.m. Goldschmidt Conference Program And Abstracts, Held May 8-10th. Reston, p. A 49. abstractMantleGeochronology, Zircon, badeleyite
DS1992-0689
1992
Heaman, L.M.Heaman, L.M., LeCheminant, A.N., Rainbird, R.H.Nature and timing of Franklin igneous events, Canada: implications for a Late Proterozoic mantle plume and the break-up of LaurentiaEarth and Planetary Science Letters, Vol. 109, No. 1-2, March pp. 117-132GlobalMantle, Proterozoic
DS1992-0690
1992
Heaman, L.M.Heaman, L.M., Machado, N.Timing and origin of Midcontinent rift alkaline magmatism, North America:evidence from the Coldwell ComplexContributions to Mineralogy and Petrology, Vol. 110, No. 2-3, pp. 289-303OntarioAlkaline, Midcontinent Rift
DS1992-0691
1992
Heaman, L.M.Heaman, L.M., Machado, N.Timing and orogen of midcontinent rift alkaline magmatism, North America:evidence from the Coldwell complexMineralogy and Petrology, Vol. 110, No. 2/3, pp. 289-303OntarioTectonics, Alkaline magmatism
DS1992-1248
1992
Heaman, L.M.Rainbird, R.H., Heaman, L.M., Young, G.Sampling Laurentia: detrital zircon geochronology offers evidence for an extensive Neoproterozoic river system originating from the Grenville orogenGeology, Vol. 20, No. 4, April pp. 351-354Victoria IslandShaler Group, Geochronology
DS1993-0646
1993
Heaman, L.M.Heaman, L.M., LeCheminant, A.N.Paragenesis and uranium-lead (U-Pb) (U-Pb) systematics of baddeleyiteChemical Geology, Vol. 110, No. 1-3, November 25, pp. 95-126.GlobalGeochronology
DS1995-0030
1995
Heaman, L.M.Amelin, Yu.V., Heaman, L.M., Semenov, V.S.Uranium-lead (U-Pb) geochronology of layered mafic intrusions in the eastern BalticShield: implications for timing and duration..Precambrian Research, Vol. 75, pp. 31-46.Russia, Baltic States, Kola PeninsulaGeochronology, Pechenga, nickel, platinum group elements (PGE), Ultramafic intrusions
DS1995-0779
1995
Heaman, L.M.Heaman, L.M., Mitchell, R.H.Constraints on the emplacement of age of Yakutian province kimberlites from uranium-lead (U-Pb) (U-Pb) perovskite dating.Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 223-24.Russia, Yakutia, Ontario, Kirkland LakeGeochronology, Malo Batuobinsk, Daldyn Alakit, Kuika, Olenek, Velikan
DS1996-0343
1996
Heaman, L.M.Davis, W.J., Parrish, R.R., Roddick, J.C., Heaman, L.M.Isotopic age determinations of kimberlites and related rocks: methods andapplications.Geological Survey of Canada, LeCheminant ed, OF 3228, pp. 39-42.CanadaTechniques -Geochronology, Kimberlites
DS1996-0754
1996
Heaman, L.M.Kjarsgaard, B.A., Heaman, L.M.Distinct emplacement periods of Phanerozoic kimberlites in North America, and implications for Slave Province.northwest Territories Exploration overview 1995, March pp. 3-22. 1p. abstractNorthwest TerritoriesGeochronology, Slave Province
DS1996-0823
1996
Heaman, L.M.LeCheminant, A.N., Heaman, L.M., Van Breemen, O., et al.Mafic magmatism, mantle roots and kimberlites in the Slave CratonGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 161-169.Northwest TerritoriesCraton - dykes, plumes, rifting, Mackenzie Dyke swarm
DS1996-0998
1996
Heaman, L.M.Moser, D.E., Heaman, L.M., Krogh, T.E., Hanes, J.A.Intracrustal extension of an Archean orogen revealed using single grain Ulead zircon geothermometry.Tectonics, Vol. 15, No. 5, Oct. pp. 1093-1109.OntarioSuperior Province, Wawa domain, Geochronology, Wawa gneiss domain
DS1996-1150
1996
Heaman, L.M.Queen, M., Heaman, L.M., Hanes, J.A., Archibald, B.A.40Ar/39Ar phlogopite and U- lead perovskite dating of lamprophyre dykes From the eastern Lake Superior regionCanadian Journal of Earth Sciences, Vol. 33, No. 6, June pp. 958-965.OntarioMidcontinent Rift volcanism., Geochronology
DS1997-0495
1997
Heaman, L.M.Heaman, L.M.Global mafic magmatism at 2.45 Ga: remnants of an ancient large igneousprovince.Geology, Vol. 25, No. 4, April pp. 299-302.OntarioHearst Matachewan, Dike swarms
DS1997-0496
1997
Heaman, L.M.Heaman, L.M., Kjarsgaard, B., Creaser, R.A., CookenbooMultiple episodes of kimberlite magmatism in the Slave Province, NorthAmerica.Lithoprobe Slave/SNORCLE., pp. 14-17.Northwest TerritoriesMagmatism
DS1997-0820
1997
Heaman, L.M.Moser, D.E., Heaman, L.M.Proterozoic zircon growth in Archean lower crustal xenoliths, southern Superior craton -Contributions to Mineralogy and Petrology, Vol. 128, No. 2-3, pp. 164-175.OntarioMatachewan ocean opening, Tectonics, arc
DS1998-0600
1998
Heaman, L.M.Heaman, L.M., Creaser, R.A., Cookenboo, H.O.Zircons from eclogite in the Jericho kimberlite pipe: evidence for Proterozoic high pressure metamorphism...7th International Kimberlite Conference Abstract, pp. 325-7.Northwest TerritoriesSlave Province, geochronology, Deposit - Jericho
DS1998-0840
1998
Heaman, L.M.LeCheminant, A.N., Heaman, L.M., Kretschmar, LeCouteurComplex origins and multiple ages of mantle zircon megacrysts from Canadian and South African kimberlites.7th International Kimberlite Conference Abstract, pp. 486-8.Northwest Territories, South Africascanning electron microscope (SEM) and backscatter electron (BSE) imaging on zircons, Deposit - Drybones Bay, Kaalvallei, Leceister
DS1999-0026
1999
Heaman, L.M.Ashton, K.E., Heaman, L.M., Lewry, HartlaubAge and origin of the Jan Lake Complex: a glimpse at the buried Archean craton of the Trans Hudson Orogen.Canadian Journal of Earth Sciences, Vol. 36, No. 2, Feb. pp. 185-208.Manitoba, SaskatchewanLithoprobe, Geophysics - seismics
DS1999-0517
1999
Heaman, L.M.Noyes, A.K., Heaman, L.M.An overview of radiometric techniques used to determine kimberlite emplacement ages.Assocation of Exploration Geologists (AEG) 19th. Diamond Exploration Methods Case Histories, pp. 108-117.GlobalKimberlite, Geochronology - review
DS2000-0138
2000
Heaman, L.M.Card, C.D., Bethune, K.M., Ashton, K.E., Heaman, L.M.The Oldman Bulyea shear zone: the Nevins Lake Block - Train Lake domain boundary, eastern Rae Province.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) 2000 Conference, 4p. abstractSaskatchewan, Western CanadaDeformation - stratigraphy, Tectonics
DS2000-0380
2000
Heaman, L.M.Halls, H.C., Heaman, L.M.The paleomagnetic significance of new uranium-lead (U-Pb) age dat a from the Molson dike swarm, Causchon Lake area.Canadian Journal of Earth Sciences, Vol. 37, No. 6, June pp. 957-66.ManitobaGeochronology, Molson dyke swarm
DS2000-0400
2000
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A.Timing of eastern North American kimberlite magmatism: continental extension of the Great Meteor Hotspot trackEarth and Planetary Science Letters, Vol. 178, No. 3-4, May 30, pp. 253-68.Ontario, ManitobaGeochronology - age determinations, Magmatism - craton
DS2000-0882
2000
Heaman, L.M.Sgarbi, G.N., Heaman, L.M.uranium-lead (U-Pb) perovskite ages for Brazilian kamafugitesIgc 30th. Brasil, Aug. abstract only 1p.Brazil, ParaguayKamafugites, Geochronology
DS2001-0463
2001
Heaman, L.M.Heaman, L.M.The timing of kimberlite emplacement and implications for diamond exploration.Prospectors and Developers Association of Canada (PDAC) 2001, 1p. abstractNorthwest TerritoriesDiamond - exploration brief overview, Geochronology
DS2001-0464
2001
Heaman, L.M.Heaman, L.M., LeCheminant, A.N.Anomalous uranium-lead (U-Pb) systematics in mantle derived baddeleyite xenocrysts from Ile Bizard: evidence ...Chemical Geology, Vol. 172, No. 1-2, Feb. pp. 77-93.QuebecGeochronology, High temperature radon diffusion
DS2002-0072
2002
Heaman, L.M.Ashton, K.E., Hartlaub, R.P., Heaman, L.M.,Card, C.D.Neoarchean history of the Rae province in northern Saskatchewan: insights into Archean tectonism.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.4., p.4.SaskatchewanTectonics
DS2002-0073
2002
Heaman, L.M.Ashton, K.E., Hartlaub, R.P., Heaman, L.M.,Card, C.D.Neoarchean history of the Rae province in northern Saskatchewan: insights into Archean tectonism.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.4., p.4.SaskatchewanTectonics
DS2002-0074
2002
Heaman, L.M.Ashton, K.E., Hartlaub, R.P., Heaman, L.M.,MoreilliPaleoproterozoic history of the Rae Province in northern saskatchewan: the The lon Taitson Trans HudsonGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.4., p.4.SaskatchewanTectonics
DS2002-0075
2002
Heaman, L.M.Ashton, K.E., Hartlaub, R.P., Heaman, L.M.,MoreilliPaleoproterozoic history of the Rae Province in northern saskatchewan: the The lon Taitson Trans HudsonGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.4., p.4.SaskatchewanTectonics
DS2002-0181
2002
Heaman, L.M.Bohm, C.O., Heaman, L.M., Creaser, R.A., Corkery, SternTectonic assembly of the Trans Hudson: Superior boundary zone in northern Manitoba: Paleoarchean crustGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.11., p.11.ManitobaCollision, Geochronology
DS2002-0182
2002
Heaman, L.M.Bohm, C.O., Heaman, L.M., Creaser, R.A., Corkery, SternTectonic assembly of the Trans Hudson: Superior boundary zone in northern Manitoba: Paleoarchean crustGac/mac Annual Meeting, Saskatoon, Abstract Volume, P.11., p.11.ManitobaCollision, Geochronology
DS2002-0480
2002
Heaman, L.M.French, J.E., Heaman, L.M., Chacko, T.Feasibility of chemical U Th total Pb baddeleyite dating by electron microprobeChemical Geology, Vol. 188,1-2,pp.85-104.Northwest Territories, South AfricaGeochronology - Great Bear, Moore Lakes, Muskox, Phalaborwa, carbonatite
DS2002-0661
2002
Heaman, L.M.Hartlaub, R.P.,Heaman, L.M., Ashton, Chacko, CreaserWas there an - 2000 km long Neoarchean extensional event in the Rae Craton? Evidence from the Murmac Bay..Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.46., p.46.SaskatchewanGeochronology
DS2002-0662
2002
Heaman, L.M.Hartlaub, R.P.,Heaman, L.M., Ashton, Chacko, CreaserWas there an - 2000 km long Neoarchean extensional event in the Rae Craton? Evidence from the Murmac Bay..Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.46., p.46.SaskatchewanGeochronology
DS2002-0663
2002
Heaman, L.M.Hartlaub, R.P.,Heaman, L.M., Ashton, Chacko, CreaserExtent of Rae Craton basement: evidence of an ancient >3.7 Ga component from U Pb Nd isotope studies.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.47., p.47.SaskatchewanGeochronology
DS2002-0664
2002
Heaman, L.M.Hartlaub, R.P.,Heaman, L.M., Ashton, Chacko, CreaserExtent of Rae Craton basement: evidence of an ancient >3.7 Ga component from U Pb Nd isotope studies.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.47., p.47.SaskatchewanGeochronology
DS2002-0684
2002
Heaman, L.M.Heaman, L.M.Musings on 2.45 Ga Earth: the temporal link between global mafic magmatism and high grade metamorphism.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.48., p.48.GlobalMagmatism - igneous provinces, dykes
DS2002-0685
2002
Heaman, L.M.Heaman, L.M.Musings on 2.45 Ga Earth: the temporal link between global mafic magmatism and high grade metamorphism.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.48., p.48.GlobalMagmatism - igneous provinces, dykes
DS2002-0686
2002
Heaman, L.M.Heaman, L.M., Creaser, R.A., Cookenboo, H.O.Extreme enrichment of high field strength elements in Jericho eclogite xenoliths: a cryptic record of Paleoproterozoic subduction, partial melting...Geology, Vol. 30,6, June,pp. 507-10.Northwest Territories, NunavutMetasomatism - Slave Craton, Deposit - Jericho
DS2002-0687
2002
Heaman, L.M.Heaman, L.M., Erdmer, P., Owne, J.V.U Pb geochronologic constraints on the crustal evolution of the Long Range Inlier, Newfoundland.Canadian Journal of Earth Science, Vol.39,5, May, pp.845-65.NewfoundlandGeochronology
DS2002-0688
2002
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A.A Cretaceous corridor of kimberlite magmatism: U Pb results from the Fort a la Corne field.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.47., p.47.SaskatchewanGeochronology
DS2002-0689
2002
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A.A Cretaceous corridor of kimberlite magmatism: U Pb results from the Fort a la Corne field.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.47., p.47.SaskatchewanGeochronology
DS2002-1029
2002
Heaman, L.M.McClenaghan, M.B., Kjarsgaard, I.M., Kjardsgaard, B.A., Heaman, L.M.Mineralogy of kimberlite boulders from eskers in the Lake Timiskaming and Kirkland Lake areas, northeastern Ontario.Geological Survey of Canada Open File, No.4361, 1 CD $ 26.OntarioGeochemistry - database CD
DS2003-0128
2003
Heaman, L.M.Bohm, C.O., Heaman, L.M.Kimberlite potential of the NW Superior Craton and Superior boundary zoneManitoba Annual Convention, Nov. 13, 1/4p. abstract.ManitobaNews item - craton, hotspot
DS2003-0364
2003
Heaman, L.M.Eccles, D.R., Heaman, L.M., Luth, R.W., Creaser, R.A.Petrogenetic considerations for the Late Cretaceous northern Alberta kimberlite8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractAlbertaKimberlite petrogenesis
DS2003-0568
2003
Heaman, L.M.Heaman, L.M., Creaser, R.A., Cookenboo, H.O., Chacko, T.Multi stage modification of the mantle lithosphere beneath the Slave Craton: evidence8ikc, Www.venuewest.com/8ikc/program.htm, Session 2, POSTER abstractNunavutEclogites and Diamonds, Deposit - Jericho
DS2003-0569
2003
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A.The temporal evolution of North American kimberlite magmatism8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractCanada, United StatesKimberlite petrogenesis, Geochronology
DS2003-0570
2003
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A., Creaser, R.A.The timing of kimberlite magmatism in North America: implications for global kimberliteLithos, Vol. 71, 2-4, pp. 153-184.Northwest TerritoriesGeochronology
DS2003-1398
2003
Heaman, L.M.Upton, B.G., Emeleus, C.H., Heaman, L.M., Goodenough, K.M., Finch, A.A.Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronologyLithos, Vol. 68, 1-2, pp. 43-65.GreenlandMagmatism
DS2003-1400
2003
Heaman, L.M.Upton, B.G.J., Emeleus, C.H., Heaman, L.M., Goodenough, K.M., Finch, A.A.Magmatism of the mid-Proterozoic Gardar Province, south Greenland: chronologyLithos, Vol. 68, May, pp. 43-65.GreenlandDyke swarms, basalts
DS200412-0177
2003
Heaman, L.M.Bohm, C.O., Heaman, L.M.Kimberlite potential of the NW Superior Craton and Superior boundary zone.Manitoba Geological Survey, Nov. 13, 1/4p. abstract.Canada, ManitobaNews item - craton, hotspot
DS200412-0500
2003
Heaman, L.M.Eccles, D.R., Heaman, L.M., Luth, R.W., Creaser, R.A.Petrogenetic considerations for the Late Cretaceous northern Alberta kimberlite province.8 IKC Program, Session 7, AbstractCanada, AlbertaKimberlite petrogenesis
DS200412-0806
2004
Heaman, L.M.Hay, S.E., Heaman, L.M., Strand, P.The Churchill kimberlites: a newly discovered Diamondiferous kimberlite province in Nunavut Canada.Geological Association of Canada Abstract Volume, May 12-14, SS14-06 p. 265.abstractCanada, NunavutPetrography
DS200412-0810
2004
Heaman, L.M.Heaman, L.M., Gower, C.F., Perreault, S.The timing of Proterozoic magmatism in the Pinware terrane of southeast Labrador, easternmost Quebec and northwest Newfoundland.Canadian Journal of Earth Sciences, Vol. 41, 2, February pp. 127-150.Canada, Quebec, LabradorMagmatism, geochronology
DS200412-0811
2003
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A.The temporal evolution of North American kimberlite magmatism.8 IKC Program, Session 7, AbstractCanada, United StatesKimberlite petrogenesis Geochronology
DS200412-0812
2003
Heaman, L.M.Heaman, L.M., Kjarsgaard, B.A., Creaser, R.A.The timing of kimberlite magmatism in North America: implications for global kimberlite genesis and diamond exploration.Lithos, Vol. 71, 2-4, pp. 153-184.Canada, Northwest TerritoriesGeochronology
DS200412-1013
2004
Heaman, L.M.Kjarsgaard, I.M., McClenaghan, M.B., Kjarsgaard, B.A., Heaman, L.M.Indicator mineralogy of kimberlite boulders from eskers in the Kirkland Lake and Lake Timiskaming areas, Ontario, Canada.Lithos, Vol. 77, 1-4, Sept. pp. 705-731.Canada, Ontario, Kirkland LakeMunro, Misema River eskers, Sharp lake, geomorphology
DS200412-1272
2004
Heaman, L.M.McHattie, T.G., Heaman, L.M., Creaser, R.A., Skulski, T., Sandeman, H.Dynamic melting in an Archean mantle plume: chemical signature of Prince Albert Group komatiite and basalt, Nunavut Canada.Geochimica et Cosmochimica Acta, 13th Goldschmidt Conference held Copenhagen Denmark, Vol. 68, 11 Supp. July, ABSTRACT p.A595.Canada, NunavutMantle plume
DS200412-1791
2004
Heaman, L.M.Sgarbi, P.B., Heaman, L.M., Gaspar, J.C.U Pb perovskite for Brazialian kamafugitic rocks: further support for a temporal link to a mantle plume hotspot track.Journal of South American Earth Sciences, Vol. 16, 8, pp. 715-724.South America, Brazil, GoiasGeochemistry, geochronology, alkaline province
DS200412-2024
2003
Heaman, L.M.Upton, B.G., Emeleus, C.H., Heaman, L.M., Goodenough, K.M., Finch, A.A.Magmatism of the mid-Proterozoic Gardar Province, South Greenland: chronology, petrogenesis and geological setting.Lithos, Vol. 68, 1-2, pp. 43-65.Europe, GreenlandMagmatism
DS200412-2026
2003
Heaman, L.M.Upton, B.G.J., Emeleus, C.H., Heaman, L.M., Goodenough, K.M., Finch, A.A.Magmatism of the mid-Proterozoic Gardar Province, south Greenland: chronology, petrogenesis and geological setting.Lithos, Vol. 68, May, pp. 43-65.Europe, GreenlandDyke swarms, basalts
DS200412-2238
2003
Heaman, L.M.Zonneveld, J.P., Kjarsgaard, B.A., Harvey, S.E., Marcia, K.Y., McNeil, D., Heaman, L.M., White, D.J.Sedimentologic and stratigrahic constraints on emplacement of the Star kimberlite, east central Saskatchewan.8 IKC Program, Session 1, AbstractCanada, SaskatchewanGeology, economics Deposit - Star
DS200512-0303
2004
Heaman, L.M.French, J.E., Heaman, L.M., Chacko, T., Rivard, B.Global mafic magmatism and continental breakup at 2.2 Ga: evidence from the Dharwar Craton, India.Geological Society of America Annual Meeting ABSTRACTS, Nov. 7-10, Paper 142-10, Vol. 36, 5, p. 340.IndiaMagmatism
DS200512-0411
2004
Heaman, L.M.Heaman, L.M.2.5-2.4 GA global magmatism: remnants of supercontinents or production of superplumes?Geological Society of America Annual Meeting ABSTRACTS, Nov. 7-10, Paper 105-5, Vol. 36, 5, p.255.MantleMagmatism, cratons, age determinations, geochronology
DS200512-0882
2005
Heaman, L.M.Purves, M.C., Heaman, L.M., Creaser, R.A., Schmidberger, S.S., Simoneti, A.Origin and isotopic evolution of the Muskox intrusion, Nunavut.GAC Annual Meeting Halifax May 15-19, Abstract 1p.Canada, NunavutLayered intrusion - ultramafic
DS200512-1036
2005
Heaman, L.M.Srivastava, R.K., Heaman, L.M., Sinha, A.K., Shihua, S.Emplacement age and isotope geochemistry of Sung Valley alkaline carbonatite complex, Shillong Plateau, northeastern India: implications for primary carbonateLithos, Vol. 81, 1-4, April pp. 33-54.IndiaMelt, silicate rocks, geochronology, Kerguelen plume
DS200512-1110
2005
Heaman, L.M.Upton, B.G.J., Ramo, O.T., Heaman, L.M., Blichert-Toft, J., Kalsbeek, F., Barry, T.L., Jepsen, H.F.The Mesoproterozoic Zig-Zag Dal basalts and associated intrusions of eastern North Greenland: mantle plume lithosphere interaction.Contributions to Mineralogy and Petrology, Vol. 149, 1, pp. 40-56.Europe, GreenlandTectonics
DS200612-0545
2005
Heaman, L.M.Hartlaub, R.P., Chacko, T., Heaman, L.M., Creaser, R.A., Ashton, K.E., Simonetti, A.Ancient (Meso-Paleoarchean) crust in the Rae Province, Canada: evidence from Sm-Nd and U-Pb constraints.Precambrian Research, Vol. 141, 3-4, Nov. 20, pp. 137-153.Canada, Saskatchewan, Alberta, Northwest TerritoriesGeochronology, crustal recycling
DS200612-0546
2006
Heaman, L.M.Hartlaub, R.P., Heaman, L.M., Simonetti, A., Bohm, C.O.Relicts of Earth's crust: U Pb, Lu Hf and morphological characteristics of > 3.7 Ga detrital zircon of the western Canadian Shield.Geological Society of America, Processes on the Earth, Special Paper 405, Chapter 5.CanadaGeochronology
DS200612-0547
2006
Heaman, L.M.Harvey, S., Kjarsgaard, B.A., Zonneveld, J.P., Heaman, L.M., McNeil, D.Volcanology and sedimentology of distinct eruptive phases at the Star kimberlite, Fort a la Corne field, Saskatchewan.Emplacement Workshop held September, 5p. extended abstractCanada, SaskatchewanDeposit - Star geology
DS200612-0556
2006
Heaman, L.M.Heaman, L.M., Creaser, R.A., Cookenboo, H.O., Chacko, T.Multi stage modification of the northern Slave mantle lithosphere: evidence from zircon and diamond bearing eclogite xenoliths entrained in Jericho kimberlite.Journal of Petrology, Vol. 47, 4, April pp. 821-858.Canada, NunavutGeochronology - Jericho
DS200612-0706
2006
Heaman, L.M.Kjarsgaard, B.A., Harvey, S.E., Zonneveld, J.P., Heaman, L.M., White, D., MacNeil, D.Volcanic stratigraphy, eruptive sequences and emplacement of the 140/141 kimberlite Fort a la Corne field, Saskatchewan.Emplacement Workshop held September, 5p. extended abstractCanada, SaskatchewanDeposit - 140/141 geology
DS200612-1240
2005
Heaman, L.M.Schmidberger, S.S., Heaman, L.M., Simonetti, A., Craser, R.A., Cookenboo, H.O.Formation of Paleoproterozoic eclogitic mantle Slave Province ( Canada): insights from in-situ Hf and U-Pb isotopic analyses of mantle zircons.Earth and Planetary Science Letters, Vol. 240, 3-4, Dec. 15, pp. 621-633.Canada, Northwest TerritoriesJericho, subduction, Archean
DS200612-1411
2006
Heaman, L.M.Tappe, S., Foley, S.F., Jenner, G.A., Heaman, L.M., Kjarsgaard, B.A., Romer,R.L., Stracke, A., Joyce, HoefsGenesis of ultramafic lamprophyres and carbonatites at Aillik Bay, Labrador: a consequence of incipient lithospheric thinning beneath the North Atlantic CratonJournal of Petrology, Vol. 47,7, pp. 1261-1315.Canada, LabradorCarbonatite
DS200712-0284
2006
Heaman, L.M.Eccles, D.R., Creaser, R.A., Heaman, L.M., Sweet, A.R., Ward, J.Geochronology and setting of Late Cretaceous to Paleocene kimberlites in the Buffalo Head Hills, north central Alberta.34th Yellowknife Geoscience Forum, p. 20-21. abstractCanada, AlbertaGeochronology
DS200712-0580
2007
Heaman, L.M.Krauss, C., Chacko, T., Heaman, L.M.Petrological and geochronological investigation of lower crustal xenoliths from the Diavik diamond mine, Slave Craton NWT.Geological Association of Canada, Gac-Mac Yellowknife 2007, May 23-25, Volume 32, 1 pg. abstract p.45.Canada, Northwest TerritoriesDiavik - geochronology
DS200712-0951
2007
Heaman, L.M.Schmidberger, S.S., Simonetti, A., Heaman, L.M., Creaser, R.A., Whieford, S.Lu Hf in-situ Sr and Pb isotope trace element systematics for mantle eclogites from the Diavik diamond mine: evidence for Paleproterozoic subduction..Earth and Planetary Science Letters, Vol. 254, 1-2, Feb. 15, pp. 55-68.Canada, Northwest TerritoriesDeposit - Diavik, geochronology, Slave Craton
DS200712-1000
2006
Heaman, L.M.Smart, K.A., Heaman, L.M., Chacko, T.Preliminary geochemistry and geothermobarometry of mantle eclogite xenoliths from the Jericho kimberlite, Nunavut.34th Yellowknife Geoscience Forum, p. 100. abstractCanada, NunavutJericho - xenoliths
DS200712-1001
2007
Heaman, L.M.Smart, K.A., Heaman, L.M., Chacko, T., Simonetti, A., Kopylova, M.Mineral chemistry and clinopyroxene Sr Pb isotope compositions of mantle eclogite xenoliths from the Jericho kimberlite, Nunavut.Geological Association of Canada, Gac-Mac Yellowknife 2007, May 23-25, Volume 32, 1 pg. abstract p.76.Canada, NunavutMineral chemistry
DS200712-1068
2007
Heaman, L.M.Tappe, S., Foley, S.F., Heaman, L.M., Romer, R.E., Stracke, A., Kjarsgaard, B.A., Jenner, G.A.Interactions between carbonate magmas and MARID metasomes: the case of Diamondiferous aillikites from the Torngat Mountains, Canada.Plates, Plumes, and Paradigms, 1p. abstract p. A1003.Canada, LabradorAillikite, magmatism
DS200812-0059
2008
Heaman, L.M.Aulbach, S., Creaser, R.A.,Heaman, L.M., Simonetti, S.S., Griffin, W.L., Stachel, T.Sulfides, diamonds and eclogites: their link to peridotites and Slave Craton hydrothermal evolution.Goldschmidt Conference 2008, Abstract p.A36.Canada, Northwest TerritoriesDeposit - A 154, geochronology
DS200812-0202
2008
Heaman, L.M.Chamberlain, K.R., Harrison, T.M., Schmitt, A.K., Heaman, L.M., Swapp, S.M., Khudoley, A.K.In situ SIMS microbaddeleyite U Pb dating method for mafic rocks.Goldschmidt Conference 2008, Abstract p.A147.TechnologyGeochronology
DS200812-0311
2008
Heaman, L.M.Eccles, D.R., Creaser, R.A., Heaman, L.M., Ward, J.RbSr and UpB geochronology and setting of the Buffalo Head Hills kimberlite field, northern Alberta.Canadian Journal of Earth Sciences, Vol. 45, 5, pp. 513-529.Canada, AlbertaGeochronology
DS200812-0312
2008
Heaman, L.M.Eccles, D.R., Heaman, L.M., Sweet, A.R.Kimberlite sourced bentonite; its paleoenvironment and implications for the Late Cretaceous K14 kimberlite cluster, northern Alberta.Canadian Journal of Earth Sciences, Vol. 45, 5, pp. 531-547.Canada, AlbertaK 14 project
DS200812-0366
2008
Heaman, L.M.Frei, D., Hutchinson, M.T., Gerdes, A., Heaman, L.M.Common lead corrected U Pb age dating of perovskite by laser ablation - magnetic sectorfield ICP-MS9IKC.com, 3p. extended abstractMantleGeochronology
DS200812-0367
2008
Heaman, L.M.French, J.E., Heaman, L.M., Chacko, T., Srivastava, R.K.1891-1883 Ma southern Bastar-Cuddapah mafic igneous events, India: a newly recognized large igneous province.Precambrian Research, Vol. 160, pp. 308-322.IndiaGeochronology - sill
DS200812-0459
2008
Heaman, L.M.Heaman, L.M.Precambrian Large Igneous Provinces: an overview of geochronology, origins and impact on Earth evolution.Journal of the Geological Society of India, Vol. 72, 1, pp. 15-34.GlobalIgneous rocks
DS200812-0496
2008
Heaman, L.M.Hutchison, M.T., Heaman, L.M.Chemical and physical characteristics of diamond crystals from Garnet Lake, Sarfartoq, West Greenland: an association with carbonatitic magmatism.Canadian Mineralogist, Vol. 46, 4, August pp.Europe, GreenlandDiamond morphology, crystallography
DS200812-1082
2008
Heaman, L.M.Smart, K.A., Heaman, L.M., Chocko, T., Simonetti, A., Kopylova, M., Mah, D., Daniels, D.The origin of diamond rich high MGO eclogite xenoliths from the Jericho kimberlite, Nunavut.Northwest Territories Geoscience Office, p. 56-57. abstractCanada, NunavutDeposit - Jericho
DS200812-1152
2008
Heaman, L.M.Tappe, S., Foley, S.F., Kjarsgaard, B.A, Romer, R.L., Heaman, L.M., Stracke, A., Jenner, G.A.Origin of Diamondiferous Torngat ultramafic lamprophyres and the role of multiple MARID type and carbonatitic vein metasomatized cratonic mantle ...9IKC.com, 3p. extended abstractCanada, Quebec, LabradorGenesis of SiO2 poor potassic melts
DS200812-1153
2008
Heaman, L.M.Tappe, S., Foley, S.F., Kjarsgaard, B.A., Romer, R.L., Heaman, L.M., Stracke, A., Jenner, G.A.Between carbonatite and lamproite - Diamondiferous Torngat ultramafic lamprohyres formed by carbonate fluxed melting of cratonic Marid type metasomes.Geochimica et Cosmochimica Acta, Vol. 72, 13, pp. 3258-3286.Canada, Labrador, QuebecTorngat
DS200812-1154
2008
Heaman, L.M.Tappe, S., Steenfelt, A., Heaman, L.M., Romer, R.J., Simonetti, A., Muehlenbachs, K.The alleged carbonatitic kimberlitic melt continuum: contrary evidence from West Greenland.Goldschmidt Conference 2008, Abstract p.A934.Europe, GreenlandDeposit - Safartoq
DS200812-1330
2008
Heaman, L.M.Zurevinski, S., Heaman, L.M., Creaser, R.A., Strand, P.The newly discovered Churchill kimberlite field, Canada: petrography, mineral chemistry and geochronology.9IKC.com, 3p. extended abstractCanada, NunavutMineralogy
DS200812-1331
2008
Heaman, L.M.Zurevinski, S.E., Heaman, L.M., Creaser, R.A., Strand, P.The Churchill kimberlite field, Nunavut, Canada: petrography, mineral chemistry, and geochronology.Canadian Journal of Earth Sciences, Vol. 45, 8, pp. 1039-1059.Canada, NunavutDeposit - Churchill district
DS200812-1332
2008
Heaman, L.M.Zurevisnki, S., Heaman, L.M., Eichenberg, D.The geochemistry of Diavik kimberlites, Lac de Gras, NWT, Canada.9IKC.com, 3p. extended abstractCanada, Northwest TerritoriesDeposit - Diavik
DS200912-0018
2009
Heaman, L.M.Aulbach, S., Creaser, R.A., Pearson, N.J., Simonetti, S.S., Heaman, L.M., Griffin, W.L., Stachel, T.Sulfide and whole rock Re-Os systematics of eclogite and pyroxenite xenoliths from the Slave Craton, Canada.Earth and Planetary Science Letters, in press available,Canada, Northwest TerritoriesDeposit - Diavik
DS200912-0183
2009
Heaman, L.M.Doornbos, C., Heaman, L.M., Doupe, J.P., England, J., Simonetti, A., Lejeunesse, P.The first integrated use of in situ U Pb geochronology and geochemical analyses to determine long distance transport of glacial erratics from maIn land Canada into western Arctic Archipelgo.Canadian Journal of Earth Sciences, Vol. 46, 2, pp. 101-122.Canada, Melville PeninsulaGeochronology - western Arctic Archipelago
DS200912-0290
2009
Heaman, L.M.Heaman, L.M.The application of U Pb geochronology to mafic, ultramafic and alkaline rocks: an evaluation of three mineral standards.Chemical Geology, Vol. 261, 1-2, pp. 42-51.TechnologyGeochonology
DS200912-0681
2009
Heaman, L.M.Secher, K., Heaman, L.M., Nielsen, T.F.D., Jensen, S.M., Schjeth, F., Creaser, R.A.Timing of kimberlite, carbonatite and ultramafic lamprophyric emplacement in the alkaline province located at 64 - 67 N in southern West Greenland.Lithos, In press available, 21p.Europe, GreenlandGeochronology
DS200912-0698
2009
Heaman, L.M.Smart, K.A., Chacko, T., Heaman, L.M., Simoneti, A.Origin of diamond rich, high MGO eclogite xenoliths from the Jericho kimberlite, Nuanvut.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyCanada, NunavutDeposit - Jericho geochemistry
DS200912-0699
2009
Heaman, L.M.Smart, K.A., Chacko, T., Heaman, L.M., Stachel, T., Muehlenbachs, K.Multiple origins of eclogitic diamonds from the Jericho kimberlite, Nunavut.37th. Annual Yellowknife Geoscience Forum, Abstracts p. 58-59.Canada, NunavutDiamond genesis
DS200912-0700
2009
Heaman, L.M.Smart, K.A., Heaman, L.M., Chacko, T.Jericho eclogites of the Slave Craton record multiple subduction related crust formation events.Goldschmidt Conference 2009, p. A1238 Abstract.Canada, Northwest TerritoriesDeposit - Jericho
DS200912-0701
2009
Heaman, L.M.Smart, K.A., Heaman, L.M., Chacko, T., Simonetti, A., Kopylova, M., Mah, D., Daniels, D.The origin of hig MgO diamond eclogites from the Jericho kimberlite, Canada.Earth and Planetary Science Letters, Vol. 284, 3-4, pp. 527-537.Canada, NunavutDeposit - Jericho
DS200912-0745
2009
Heaman, L.M.Tappe, S., Heaman, L.M., Romer, R.L., Steenfelt, A., Simonetti, A., Muehlenbach, K., Stracke, A.Quest for primary carbonatite melts beneath cratons: a West Greenland perspective.Goldschmidt Conference 2009, p. A1314 Abstract.Europe, GreenlandCarbonatite
DS200912-0746
2009
Heaman, L.M.Tappe, S., Heaman, L.M., Smart, K.A., Muehlenbachs, K., Simonetti, A.First results from Greenland eclogite xenoliths: evidence for an ultra depleted peridotitic component within the North Atlantic craton mantle lithosphere.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyEurope, GreenlandMelting
DS200912-0747
2009
Heaman, L.M.Tappe, S., Sleenfelt, A., Heaman, L.M., Simonetti, A.The newly discovered Jurassic Tikusaaq carbonatite allikite occurrence, West Greenland, and some remarks on carbonatite kimberlite relationships.Lithos, in press availableEurope, GreenlandPetrology
DS201012-0024
2009
Heaman, L.M.Aulbach, S., Stachel, T., Craeser, R.A., Heaman, L.M., Shirey, S.B., MUehlenbachs, K., Eichenberg, D., HarrisSulphide survival and diamond genesis during formation and evolution of Archean subcontinental lithosphere: a comparison between the Slave and Kaapvaal cratons.Lithos, Vol. 112 S pp. 747-757.Canada, AfricaGeochronology
DS201012-0026
2010
Heaman, L.M.Aulbach, S., Stachel, T., Heaman, L.M., Creaser, R.A., Shirey, S.B.Formation of cratonic subcontinental lithospheric mantle and complementary komatiite from hybrid plume sources.Contributions to Mineralogy and Petrology, In press available, 14p.Canada, Northwest TerritoriesPeridotitic sulphide inclusions in diamonds - SCLM
DS201012-0274
2010
Heaman, L.M.Heaman, L.M., Pearson, D.G.Nature and evolution of the Slave Province subcontinental lithospheric mantle.Canadian Journal of Earth Sciences, Vol. 47, 4, pp. 369-388.Canada, Northwest TerritoriesGeophysics - seismic
DS201012-0430
2010
Heaman, L.M.Lehman, B., Burgess, R., Frei, D., Belyatsky, B., Mainkar, D., Chalapthi Rao, N.V., Heaman, L.M.Diamondiferous kimberlites in central India synchronous with Deccan flood basalts.Earth and Planetary Science Letters, Vol. 290, 1-2, Feb. 15, pp. 142-149.IndiaMineral chemistry
DS201012-0431
2010
Heaman, L.M.Lehmann, B., Burgess, R., Frei, D., Belyatsky, B., Mainkar, D., Chalapthi Rao, N.V., Heaman, L.M.Diamondiferous kimberlites in central India synchronous with Deccan flood basalts.International Dyke Conference Held Feb. 6, India, 1p. AbstractIndiaDharwar and Bundelkhand cratons
DS201012-0778
2010
Heaman, L.M.Tappe, S., Heaman, L.M.Can alkaline magmatism destroy a craton? Lessons learned from the Greenland Labrador diamond province.International Dyke Conference Held Feb. 6, India, 1p. AbstractCanada, Labrador, Europe, GreenlandAlkaline rocks, magmatism
DS201112-0045
2011
Heaman, L.M.Aulbach, S., Stachel, T., Heaman, L.M., Creaser, R.A., Shirey, S.B.Formation of cratonic subcontinental lithospheric mantle and complementary komatiite from hybrid plume sources.Contributions to Mineralogy and Petrology, Vol. 161, 6, pp. 947-960.MantleHotspots
DS201112-0046
2011
Heaman, L.M.Aulbach, S., Stachel, T., Heaman, L.M., Creaser, R.A.,Thomassot, E., Shirey, S.B.C and S transfer in subduction zones: insight from diamonds.Goldschmidt Conference 2011, abstract p.462.Canada, Northwest TerritoriesDiavik, Ekati
DS201112-0499
2011
Heaman, L.M.Kamo, S.L., Corfu, F., Heaman, L.M., Moser, D.E.The Krogh revolution: advances in the measurement of time.Canadian Journal of Earth Sciences, Vol. 48, 2, pp. 87-94.TechnologyGeochronology
DS201112-0974
2011
Heaman, L.M.Smart, K.A., Chacko, T., Stachel, T., Muehlenbachs, K., Stern, R.A., Heaman, L.M.Diamond growth from oxidized carbon sources beneath the Northern Slave Craton, Canada: A delta 13 C-N study of eclogite hosted diamonds from the Jericho kimberlite.Geochimica et Cosmochimica Acta, Vol. 75, pp. 6027-6047.Canada, NunavutJericho - diamond morphology
DS201112-1177
2011
Heaman, L.M.Zurevinski, S.E.,Heaman, L.M., Creaser, R.A.The origin of Triassic/Jurassic kimberlite magmatism, Canada: two mantle sources revealed from the Sr-Nd isotopic composition of groundmass perovskite.Geochemical, Geophysics, Geosystems: G3, Vol. 12, 10.1029Canada, Ontario, Quebec, LabradorCorridor - Timiskaming, Rankin, Attawapiskat, Kirkland
DS201212-0040
2012
Heaman, L.M.Aulbach, S., Stachel, T., Heaman, L.M., Creaser, R.A., Seitz, H.M., Shirey, S.B.Diamond formation in the slab and mantle wedge: examples from the Slave Craton.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractCanada, Northwest TerritoriesDiamond genesis
DS201212-0265
2012
Heaman, L.M.Grutter, H.S., Gerdes, A., Marko, L., Heaman, L.M.U-Pb geochronology of perovskite and zircon from the Chigicherla kimberlites, Anatapur district, India.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractIndiaDeposit - Chigicherla
DS201312-0223
2013
Heaman, L.M.Donatti-Filho, J.P., Tappe, S., Oliveira, E.P., Heaman, L.M.Age and origin of Neoproterozoic Brauna kimberlitic melt generation with the metasomatized base of Sao Francisco craton, BrazilChemical Geology, Vol. 353, pp. 19-35.South America, BrazilGeochronology, geochemistry (kimberlites and orangeites)
DS201412-0729
2014
Heaman, L.M.Reiminik, J.R., Chacko, T., Stern, R.A., Heaman, L.M.Earth's earliest evolved crust generated in an Iceland-like setting.Nature Geoscience, Vol. 7, pp. 529-533.Europe, IcelandMagmatism, upwelling mantle rocks
DS201412-0841
2014
Heaman, L.M.Smart, K.A., Chacko, T., Simonetti, A., Sharp, Z.D., Heaman, L.M.A record of Paleoproterozoic subduction preserved in the northern Slave cratonic mantle: Sr-Pb-O isotope and trace element investigations of eclogite xenoliths from the Jericho and Muskox kimberlites.Journal of Petrology, Vol. 55, 3, pp. 549-583.Canada, NunavutDeposit - Jericho, Muskox
DS201504-0201
2015
Heaman, L.M.Heaman, L.M., Pell, J., Grutter, H.S., Creaser, R.A.U-Pb geochronology and Sr/Nd isotope compositions of groundmass perovskite from the newly discovered Jurassic Chidliak kimberlite field, Baffin Island, Canada.Earth and Planetary Science Letters, Vol. 415, April pp. 183-189.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS201504-0215
2015
Heaman, L.M.Sarkar, C., Heaman, L.M., Pearson, D.G.Duration and periodicity of kimberlite volcanic activity in the Lac de Gras kimberlite field, Canada and some recommendations for kimberlite geochronology.Lithos, Vol. 218-219, pp. 155-166.Canada, Northwest TerritoriesDeposit - Eddie
DS201506-0281
2015
Heaman, L.M.Kent, D.V., Kjarsgaard, B.A., Gee, J.S., Muttoni, G., Heaman, L.M.Tracking the Late Jurassic apparent ( or true) polar shift in U-Pb-dated kimberlites from cratonic North America ( Superior Province of Canada).Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 4, pp. 983-994.Canada, Ontario, TimiskamingDeposit - Peddie
DS201606-1084
2016
Heaman, L.M.Evans, D.A.D., Trindade, R.I.F., Catelani, E.L., D'Agrella-Filho, Heaman, L.M., Oliveira, E.P., Soderlund, U., Ernst, R.E., Smirnovm A.V., Salminen, J.M.Return to Rodinia? Moderate to high paleolatitude of the Sao Francisco/Congo craton at 920 Ma.Geological Society of London Special Publication Supercontinent Cycles through Earth History., Vol. 424, pp. 167-190.South America, BrazilSupercontinents

Abstract: Moderate to high palaeolatitudes recorded in mafic dykes, exposed along the coast of Bahia, Brazil, are partly responsible for some interpretations that the São Francisco/Congo craton was separate from the low-latitude Rodinia supercontinent at about 1050 Ma. We report new palaeomagnetic data that replicate the previous results. However, we obtain substantially younger U-Pb baddeleyite ages from five dykes previously thought to be 1.02- 1.01 Ga according to the 40 Ar/ 39 Ar method. Specifically, the so-called 'A-normal' remanence direction from Salva-dor is dated at 924.2 + 3.8 Ma, within error of the age for the 'C' remanence direction at 921.5 + 4.3 Ma. An 'A-normal' dyke at Ilhéus is dated at 926.1 + 4.6 Ma, and two 'A-normal' dykes at Olivença have indistinguishable ages with best estimate of emplacement at 918.2 + 6.7 Ma. We attribute the palaeomagnetic variance of the 'A-normal' and 'C' directions to lack of averaging of geomagnetic palaeosecular variation in some regions. Our results render previous 40 Ar/ 39 Ar ages from the dykes suspect, leaving late Mesoproterozoic palaeolatitudes of the São Francisco/Congo craton unconstrained. The combined 'A-normal' palaeomagnetic pole from coastal Bahia places the São Francisco/Congo craton in moderate to high palaeolatitudes at c. 920 Ma, allowing various possible positions of that block within Rodinia. Despite more than two decades of intense global research, the configuration of Neoproterozoic supercontinent Rodinia remains enigmatic. Following the first global synthesis by Hoffman (1991), most models include a central location for Laurentia, flanked by 'East' Gondwana-Land cra-tons along its proto-Cordilleran margin and 'West'
DS201610-1903
2016
Heaman, L.M.Reimink, J.R., Davies, J.H.F.L., Chacko, T., Stern, R.A., Heaman, L.M., Sarkar, C., Schaltegger, U., Creaser, R.A., Pearson, D.G.No evidence for Hadean continental crust within Earth's oldest evolved rock unit. (Acasta Gneiss Complex)Nature Geoscience, Vol. 9, pp. 777-780.CanadaHadean crust

Abstract: Due to the acute scarcity of very ancient rocks, the composition of Earth’s embryonic crust during the Hadean eon (>4.0 billion years ago) is a critical unknown in our search to understand how the earliest continents evolved. Whether the Hadean Earth was dominated by mafic-composition crust, similar to today’s oceanic crust1, 2, 3, 4, or included significant amounts of continental crust5, 6, 7, 8 remains an unsolved question that carries major implications for the earliest atmosphere, the origin of life, and the geochemical evolution of the crust-mantle system. Here we present new U-Pb and Hf isotope data on zircons from the only precisely dated Hadean rock unit on Earth—a 4,019.6 ± 1.8?Myr tonalitic gneiss unit in the Acasta Gneiss Complex, Canada. Combined zircon and whole-rock geochemical data from this ancient unit shows no indication of derivation from, or interaction with, older Hadean continental crust. Instead, the data provide the first direct evidence that the oldest known evolved crust on Earth was generated from an older ultramafic or mafic reservoir that probably surfaced the early Earth.
DS201612-2329
2016
Heaman, L.M.Reimink, J.R., Davies, J.H.F.L., Chacko, T., Stern, R.A., Heaman, L.M., Sarkar, C., Schaltegger, U., Creaser, R.A., Pearson, D.G.No evidence for Hadean continental crust within Earth's oldest evolved rock unit.Nature Geoscience, Vol. 9, pp. 777-780.CanadaAcasta Gneiss

Abstract: Due to the acute scarcity of very ancient rocks, the composition of Earth’s embryonic crust during the Hadean eon (>4.0 billion years ago) is a critical unknown in our search to understand how the earliest continents evolved. Whether the Hadean Earth was dominated by mafic-composition crust, similar to today’s oceanic crust1, 2, 3, 4, or included significant amounts of continental crust5, 6, 7, 8 remains an unsolved question that carries major implications for the earliest atmosphere, the origin of life, and the geochemical evolution of the crust-mantle system. Here we present new U-Pb and Hf isotope data on zircons from the only precisely dated Hadean rock unit on Earth—a 4,019.6 ± 1.8?Myr tonalitic gneiss unit in the Acasta Gneiss Complex, Canada. Combined zircon and whole-rock geochemical data from this ancient unit shows no indication of derivation from, or interaction with, older Hadean continental crust. Instead, the data provide the first direct evidence that the oldest known evolved crust on Earth was generated from an older ultramafic or mafic reservoir that probably surfaced the early Earth.
DS201703-0396
2017
Heaman, L.M.Almeida, V.V., Janasi, V.A., Heaman, L.M., Shaulis, B.J., Hollanda, M.H.B.M., Renne, P.R.Contemporaneous alkaline and tholeiitic magmatism in the Ponta Grossa Arch, Parana Etendeka magmatic province: constraints from U-Pb zircon baddeleyite and 40Ar/39Ar phlogopite dating of the Jose Fernandes gabbro and mafic dykes.Journal of Volcanology and Geothermal Research, in press available 11p.South America, BrazilAlkaline rocks

Abstract: We report the first high-precision ID-TIMS U-Pb baddeleyite/zircon and 40Ar/39Ar step-heating phlogopite age data for diabase and lamprophyre dykes and a mafic intrusion (José Fernandes Gabbro) located within the Ponta Grossa Arch, Brazil, in order to constrain the temporal evolution between Early Cretaceous tholeiitic and alkaline magmatism of the Paraná-Etendeka Magmatic Province. U-Pb dates from chemically abraded zircon data yielded the best estimate for the emplacement ages of a high Ti-P-Sr basaltic dyke (133.9 ± 0.2 Ma), a dyke with basaltic andesite composition (133.4 ± 0.2 Ma) and the José Fernandes Gabbro (134.5 ± 0.1 Ma). A 40Ar/39Ar phlogopite step-heating age of 133.7 ± 0.1 Ma from a lamprophyre dyke is identical within error to the U-Pb age of the diabase dykes, indicating that tholeiitic and alkaline magmatism were coeval in the Ponta Grossa Arch. Although nearly all analysed fractions are concordant and show low analytical uncertainties (± 0.3-0.9 Ma for baddeleyite; 0.1-0.4 Ma for zircon; 2?), Pb loss is observed in all baddeleyite fractions and in some initial zircon fractions not submitted to the most extreme chemical abrasion treatment. The resulting age spread may reflect intense and continued magmatic activity in the Ponta Grossa Arch.
DS201709-2016
2017
Heaman, L.M.Kjarsgaard, B.A., Heaman, L.M., Sarkar, C., Pearson, D.G.The North American mid-Cretaceous kimberlite corridor: wet, edge-driven decompression melting of an OIB-type deep mantle source.Geochemistry, Geophysics, Geosystems: G3, Vol. 18, 7, pp. 2727-2747.Canada, Somerset Island, Saskatchewan, United States, Kansasmagmatism, convection, diamond genesis

Abstract: Thirty new high-precision U-Pb perovskite and zircon ages from kimberlites in central North America delineate a corridor of mid-Cretaceous (115–92 Ma) magmatism that extends ?4000 km from Somerset Island in Arctic Canada through central Saskatchewan to Kansas, USA. The least contaminated whole rock Sr, Nd, and Hf isotopic data, coupled with Sr isotopic data from groundmass perovskite indicates an exceptionally limited range in Sr-Nd-Hf isotopic compositions, clustering at the low ?Nd end of the OIB array. These isotopic compositions are distinct from other studied North American kimberlites and point to a sublithospheric source region. This mid-Cretaceous kimberlite magmatism cannot be related to mantle plumes associated with the African or Pacific large low-shear wave velocity province (LLSVP). All three kimberlite fields are adjacent to strongly attenuated lithosphere at the edge of the North American craton. This facilitated edge-driven convection, a top-down driven processes that caused decompression melting of the transition zone or overlying asthenosphere. The inversion of ringwoodite and/or wadsleyite and release of H2O, with subsequent metasomatism and synchronous wet partial melting generates a hot CO2 and H2O-rich protokimberlite melt. Emplacement in the crust is controlled by local lithospheric factors; all three kimberlite fields have mid-Cretaceous age, reactivated major deep-seated structures that facilitated kimberlite melt transit through the lithosphere.
DS201809-2082
2018
Heaman, L.M.Sarkar, C., Kjarsgaard, B.A., Pearson, D.G., Heaman, L.M., Locock, A.J., Armstrong, J.P.Geochronology, classification and mantle source characteristics of kimberlites and related rocks from the Rae craton, Melville Peninsula, Nunavut, Canada.Mineralogy and Petrology, doi.org/10.1007/ s00710-018-0632-5 20p.Canada, Nunavut, Melville Peninsuladeposit - Pelly Bay, Darby, Aviat, Qilalugaq

Abstract: Detailed geochronology along with petrographic, mineralogical and geochemical studies have been conducted on recently found diamond-bearing kimberlitic and related rocks in the Rae Craton at Aviat and Qilalugaq, Melville Peninsula, north-east Canada. Magmatic rocks from the Aviat pipes have geochemical (both bulk rock and isotopic) and mineralogical signatures (e.g., core to rim Al and Ba enrichment in phlogopite) similar to Group I kimberlite. In contrast, Aviat intrusive sheets are similar to ‘micaceous’ Group II kimberlite (orangeite) in their geochemical and mineralogical characteristics (e.g., phlogopite and spinel compositions, highly enriched Sr isotopic signature). Qilalugaq rocks with the least crustal contamination have geochemical and mineralogical signatures [e.g., high SiO2, Al2O3 and H2O; low TiO2 and CO2; less fractionated REE (rare earth elements), presence of primary clinopyroxene, phlogopite and spinel compositions] that are similar to features displayed by olivine lamproites from Argyle, Ellendale and West Greenland. The Naujaat dykes, in the vicinity of Qilalugaq, are highly altered due to extensive silicification and carbonation. However, their bulk rock geochemical signature and phlogopite chemistry are similar to Group I kimberlite. U-Pb perovskite geochronology reveals that Aviat pipes and all rocks from Qilalugaq have an early Cambrian emplacement age (540-530 Ma), with the Aviat sheets being ~30 Ma younger. This volatile-rich potassic ultramafic magmatism probably formed by varying degrees of involvement of asthenospheric and lithospherically derived melts. The spectrum of ages and compositions are similar to equivalent magmatic rocks observed from the nearby north-eastern North America and Western Greenland. The ultimate trigger for this magmatism could be linked to Neoproterozoic continental rifting during the opening of the Iapetus Ocean and breakup of the Rodinia supercontinent.
DS201810-2370
2018
Heaman, L.M.Ranger, I.M., Heaman, L.M., Pearson, D.G., Muntener, C., Zhuk, V.Punctuated, long lived emplacement history of the Renard 2 kimberlite, Canada, revealed by new high precision U-Pb groundmass perovskite dating. IF-TIMSMineralogy and Petrology, doi.org/101007/ s00710-018-0629-0 13p.Canada, Quebecdeposit - Renard

Abstract: Kimberlites are rare volatile-rich ultramafic magmas thought to erupt in short periods of time (<1 Myr) but there is a growing body of evidence that the emplacement history of a kimberlite can be significantly more protracted. In this study we report a detailed geochronology investigation of a single kimberlite pipe from the Renard cluster in north-central Québec. Ten new high precision ID-TIMS (isotope dilution - thermal ionization mass spectrometry) U-Pb groundmass perovskite dates from the main pipe-infilling kimberlites and several small hypabyssal kimberlites from the Renard 2 pipe indicate kimberlite magmatism lasted at least ~20 Myr. Two samples of the main pipe-infilling kimberlites yield identical weighted mean 206Pb/238U perovskite dates with a composite date of 643.8?±?1.0 Myr, interpreted to be the best estimate for main pipe emplacement. In contrast, six hypabyssal kimberlite samples yielded a range of weighted mean 206Pb/238U perovskite dates between ~652-632 Myr. Multiple dates determined from these early-, syn- and late-stage small hypabyssal kimberlites in the Renard 2 pipe demonstrate this rock type (commonly used to date kimberlites) help to constrain the duration of kimberlite intrusion history within a pipe but do not necessarily reliably record the emplacement age of the main diatreme in the Renard cluster. Our results provide the first robust geochronological data on a single kimberlite that confirms the field relationships initially observed by Wagner (1914) and Clement (1982); the presence of antecedent (diatreme precursor) intrusions, contemporaneous (syn-diatreme) intrusions, and consequent (post-diatreme) cross-cutting intrusions. The results of this detailed U-Pb geochronology study indicate a single kimberlite pipe can record millions of years of magmatism, much longer than previously thought from the classical viewpoint of a rapid and short-duration emplacement history.
DS201812-2776
2019
Heaman, L.M.Aulbach, S., Heaman, L.M., Jacob, D.E., Viljoen, K.S.Ages and sources of mantle eclogites: ID-TIMS and in situ MC-ICPMS Pb-Sr isotope sytematics of clinopyroxene.Chemical Geology, Vol. 503, pp. 15-28.Mantleeclogite

Abstract: Strontium and Pb isotopic compositions of clinopyroxene (cpx) in selected samples from three well-characterised eclogite suites with oceanic crustal protoliths (Lace/Kaapvaal craton, Orapa/Zimbabwe craton and Koidu/West African craton) were acquired by high-precision isotope dilution thermal ionisation mass spectrometry (ID-TIMS) and in situ multicollector-laser ablation-inductively-coupled plasma mass spectrometry (MC-LA-ICPMS). The aims of this study are twofold: (1) assess their utility to obtain formation or resetting age constraints and identify elemental signatures that enhance the chances of successful age dating, and (2) to confirm the veracity and utility of results obtained by novel MC-LA-ICPMS techniques. Strontium-Pb isotope systematics of eclogitic cpx measured in this study are decoupled and may reflect addition of unsupported radiogenic Sr during seawater alteration or interaction with oceanic sediments in subduction mélanges, and/or disturbance due to mantle metasomatism, to which the more incompatible Pb is more susceptible. Despite a complex history, subsets of samples yield meaningful model dates. Clinopyroxene fractions from Lace with high Pb contents (36?ppm), unradiogenic Pb isotopic compositions (206Pb/204Pb?=?13.5713.52) and low 238U/204Pb (1.01.5) give single-stage model Pb dates of 2.902.84?Ga. In contrast, samples from Orapa plot to the right of the Geochron and do not yield meaningful Pb model ages. However, these data do define secondary isochrons that can be modelled to yield minimum age constraints on major events affecting the cratonic lithosphere. Within the uncertainties, the resultant 2.18?±?0.45?Ga age obtained for Koidu eclogites reflect disturbance of the Pb isotope system due to subduction beneath the craton linked to the Eburnean orogeny, while they retained their unradiogenic 87Sr/86Sr (0.7016). Similarly, the age for samples from Orapa (2.20?±?0.54?Ga) is interpreted as an overprint age related to Palaeoproterozoic accretion at the western craton margin. Gabbroic eclogites (Eu/Eu*?>?1) with plagioclase-rich protoliths having low time-integrated Rb/Sr and U/Pb retain the least radiogenic Sr and, in part, Pb. High model ? (9.0 to 9.1) for several eclogites from Lace with elevated LREE, Th and Pb abundances reflects ca. 3.0?Ga addition of a sedimentary component, possibly derived from reworking of a high-? basaltic protocrust, as observed on other cratons. We suggest that sample targeting can be usefully guided by fast-throughput in situ LA-ICPMS techniques, which largely yield results identical to ID-TIMS, albeit at lower precision, and which can further help identify kimberlite contamination in the mineral separates used for solution work.
DS201812-2777
2018
Heaman, L.M.Aulbach, S., Heaman, L.M., Stachel, T.Diavik deposit: The diamondiferous mantle root beneath the central Slave craton.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp.319-342.Canada, Northwest Territoriesdeposit - Diavik
DS201902-0257
2019
Heaman, L.M.Aulbach, S., Heaman, L.M., Jacob, D., Viljoen, K.S.Ages and sources of mantle eclogites: ID-TIMS and in situ MC-ICPMS Pb-Sr isotope systematics of clinopyroxene.Chemical Geology, Vol. 503, pp. 15-28.Africa, South Africa, Zimbabwe, Sierra Leonedeposit - Lace, Orapa, Koidu

Abstract: Strontium and Pb isotopic compositions of clinopyroxene (cpx) in selected samples from three well-characterised eclogite suites with oceanic crustal protoliths (Lace/Kaapvaal craton, Orapa/Zimbabwe craton and Koidu/West African craton) were acquired by high-precision isotope dilution thermal ionisation mass spectrometry (ID-TIMS) and in situ multicollector-laser ablation-inductively-coupled plasma mass spectrometry (MC-LA-ICPMS). The aims of this study are twofold: (1) assess their utility to obtain formation or resetting age constraints and identify elemental signatures that enhance the chances of successful age dating, and (2) to confirm the veracity and utility of results obtained by novel MC-LA-ICPMS techniques. Strontium-Pb isotope systematics of eclogitic cpx measured in this study are decoupled and may reflect addition of unsupported radiogenic Sr during seawater alteration or interaction with oceanic sediments in subduction mélanges, and/or disturbance due to mantle metasomatism, to which the more incompatible Pb is more susceptible. Despite a complex history, subsets of samples yield meaningful model dates. Clinopyroxene fractions from Lace with high Pb contents (3-6?ppm), unradiogenic Pb isotopic compositions (206Pb/204Pb?=?13.57-13.52) and low 238U/204Pb (1.0-1.5) give single-stage model Pb dates of 2.90-2.84?Ga. In contrast, samples from Orapa plot to the right of the Geochron and do not yield meaningful Pb model ages. However, these data do define secondary isochrons that can be modelled to yield minimum age constraints on major events affecting the cratonic lithosphere. Within the uncertainties, the resultant 2.18?±?0.45?Ga age obtained for Koidu eclogites reflect disturbance of the Pb isotope system due to subduction beneath the craton linked to the Eburnean orogeny, while they retained their unradiogenic 87Sr/86Sr (0.7016). Similarly, the age for samples from Orapa (2.20?±?0.54?Ga) is interpreted as an overprint age related to Palaeoproterozoic accretion at the western craton margin. Gabbroic eclogites (Eu/Eu*?>?1) with plagioclase-rich protoliths having low time-integrated Rb/Sr and U/Pb retain the least radiogenic Sr and, in part, Pb. High model ? (9.0 to 9.1) for several eclogites from Lace with elevated LREE, Th and Pb abundances reflects ca. 3.0?Ga addition of a sedimentary component, possibly derived from reworking of a high-? basaltic protocrust, as observed on other cratons. We suggest that sample targeting can be usefully guided by fast-throughput in situ LA-ICPMS techniques, which largely yield results identical to ID-TIMS, albeit at lower precision, and which can further help identify kimberlite contamination in the mineral separates used for solution work.
DS201905-1018
2019
Heaman, L.M.Bohm, C.O., Hartlaub, R.P., Heaman, L.M., Cates, N., Guitreau, M., Bourdon, B., Roth, A.S.G., Mojzsis, S.J., Blichert-Toft, J.The Assean Lake Complex: ancient crust at the northwestern margin of the Superior Craton, Manitoba, Canada.Earths Oldest Rocks, researchgate.com Chapter 28, 20p. Pdf availableCanada, Manitobacraton

Abstract: This chapter describes the Assean Lake Complex (ALC) at ancient crust at the Northwestern margin of the Superior Craton, Manitoba, and Canada. An initial tectonic model for the Assean Lake area indicated that a regionally extensive high-strain zone running through the lake marks the suture between Archean high-grade crustal terranes of the Superior Craton to the southeast and Paleoproterozoic rocks of the Trans-Hudson Orogen to the northwest. Detailed geologic remapping combined with isotopic and geochemical studies led to a re-interpretation of the crust immediately north of the Assean Lake high-strain zone as Mesoarchean. The study area straddles the boundary between the Archean Superior Craton and the ca.1.90-1.84 Ga arc and marginal basin rocks of the Trans-Hudson Orogen, which represent the remains of ca. 1.83-1.76 Ga ocean closure and orogeny. It is indicated that the gneisses of the Split Lake Block consist primarily of meta-igneous protoliths of gabbroic to granitic composition. Tonalite and granodiorite are the most volumetrically dominant, but an anorthosite dome is also present in the northeast. Mapping, isotopic, and age data combined with high-resolution aero-magnetic data indicate that the Mesoarchean ALC is a crustal slice up to 10 km wide, and has a strike length of at least 50 km.
DS202002-0161
2019
Heaman, L.M.Aulbach, S., Woodland, A.B., Stern, R.A., Vasilyev, P., Heaman, L.M., Viljoen, K.S.Evidence for a dominantly reducing Archaean ambient mantle from two redox proxies, and low oxygen fugacity of deeply subducted oceanic crust.Nature Research Scientific Reports, https://doi.org/10.1038/ s41598-019-55743-1 11p. PdfMantlemelting, redox

Abstract: Privacy Policy. You can manage your preferences in 'Manage Cookies'. Oxygen fugacity (fO2) is an intensive variable implicated in a range of processes that have shaped the Earth system, but there is controversy on the timing and rate of oxidation of the uppermost convecting mantle to its present fO2 around the fayalite-magnetite-quartz oxygen buffer. Here, we report Fe3+/?Fe and ƒf2 for ancient eclogite xenoliths with oceanic crustal protoliths that sampled the coeval ambient convecting mantle. Using new and published data, we demonstrate that in these eclogites, two redox proxies, V/Sc and Fe3+/?Fe, behave sympathetically, despite different responses of their protoliths to differentiation and post-formation degassing, seawater alteration, devolatilisation and partial melting, testifying to an unexpected robustness of Fe3+/?Fe. Therefore, these processes, while causing significant scatter, did not completely obliterate the underlying convecting mantle signal. Considering only unmetasomatised samples with non-cumulate and little-differentiated protoliths, V/Sc and Fe3+/?Fe in two Archaean eclogite suites are significantly lower than those of modern mid-ocean ridge basalts (MORB), while a third suite has ratios similar to modern MORB, indicating redox heterogeneity. Another major finding is the predominantly low though variable estimated fO2 of eclogite at mantle depths, which does not permit stabilisation of CO2-dominated fluids or pure carbonatite melts. Conversely, low-fO2 eclogite may have caused efficient reduction of CO2 in fluids and melts generated in other portions of ancient subducting slabs, consistent with eclogitic diamond formation ages, the disproportionate frequency of eclogitic diamonds relative to the subordinate abundance of eclogite in the mantle lithosphere and the general absence of carbonate in mantle eclogite. This indicates carbon recycling at least to depths of diamond stability and may have represented a significant pathway for carbon ingassing through time.
DS202002-0167
2019
Heaman, L.M.Bohm, C.O., Hartlaub, R.P., Heaman, L.M., Cates, N., Guitreau, M., Bourdon, B., Roth, A.S.G., Mojzsis, S.J., Blichert-Toft, J.The Assean Lake Complex: ancient crust at the northwestern margin of the Superior craton, Manitoba, Canada. ( not specific to diamonds)Earth's Oldest Rocks, Chapter 28, 20p. Pdf.Canada, Manitobacraton
DS202007-1129
2020
Heaman, L.M.Chen, Y., Gu, Y/.J., Heaman, L.M., Wu, L., Saygin, E., Hung, S-H.Reconciling seismic structures and Late Cretaceous kimberlite magmatism in northern Alberta, Canada.Geology, Vol. 48, in press available, 5 p. pdfCanada, Albertadeposit - Birch Mountain, Mountain Lake

Abstract: The Late Cretaceous kimberlites in northern Alberta, Canada, intruded into the Paleoproterozoic crust and represent a nonconventional setting for the discovery of diamonds. Here, we examined the origin of kimberlite magmatism using a multidisciplinary approach. A new teleseismic survey reveals a low-velocity (-1%) corridor that connects two deep-rooted (>200 km) quasi-cylindrical anomalies underneath the Birch Mountains and Mountain Lake kimberlite fields. The radiometric data, including a new U-Pb perovskite age of 90.3 ± 2.6 Ma for the Mountain Lake intrusion, indicate a northeast-trending age progression in kimberlite magmatism, consistent with the (local) plate motion rate of North America constrained by global plate reconstructions. Taken together, these observations favor a deep stationary (relative to the lower mantle) source region for kimberlitic melt generation. Two competing models, mantle plume and slab subduction, can satisfy kinematic constraints and explain the exhumation of ultradeep diamonds. The plume hypothesis is less favorable due to the apparent age discrepancy between the oldest kimberlites (ca. 90 Ma) and the plume event (ca. 110 Ma). Alternatively, magma generation may have been facilitated by decompression of hydrous phases (e.g., wadsleyite and ringwoodite) within the mantle transition zone in response to thermal perturbations by a cold slab. The three-dimensional lithospheric structures largely controlled melt migration and intrusion processes during the Late Cretaceous kimberlite magmatism in northern Alberta.
DS202008-1368
2019
Heaman, L.M.Aulbach, S., Woodand, A.B., Stern, R.A., Vasileyev, P., Heaman, L.M., Viljoen, K.S.Evidence for a dominantly reducing Archean ambient mantle from two redox proxies, and low oxygen fugacity of deeply subducted oceanic crust. Nature Research Scientific Reports, Vol. 9:20190 doir.org/10.38 /s41598-019-55743-1, 11p. PdfMantleeclogite

Abstract: Oxygen fugacity (ƒO2) is an intensive variable implicated in a range of processes that have shaped the Earth system, but there is controversy on the timing and rate of oxidation of the uppermost convecting mantle to its present ƒO2 around the fayalite-magnetite-quartz oxygen buffer. Here, we report Fe3+/?Fe and ƒO2 for ancient eclogite xenoliths with oceanic crustal protoliths that sampled the coeval ambient convecting mantle. Using new and published data, we demonstrate that in these eclogites, two redox proxies, V/Sc and Fe3+/?Fe, behave sympathetically, despite different responses of their protoliths to differentiation and post-formation degassing, seawater alteration, devolatilisation and partial melting, testifying to an unexpected robustness of Fe3+/?Fe. Therefore, these processes, while causing significant scatter, did not completely obliterate the underlying convecting mantle signal. Considering only unmetasomatised samples with non-cumulate and little-differentiated protoliths, V/Sc and Fe3+/?Fe in two Archaean eclogite suites are significantly lower than those of modern mid-ocean ridge basalts (MORB), while a third suite has ratios similar to modern MORB, indicating redox heterogeneity. Another major finding is the predominantly low though variable estimated ƒO2 of eclogite at mantle depths, which does not permit stabilisation of CO2-dominated fluids or pure carbonatite melts. Conversely, low-ƒO2 eclogite may have caused efficient reduction of CO2 in fluids and melts generated in other portions of ancient subducting slabs, consistent with eclogitic diamond formation ages, the disproportionate frequency of eclogitic diamonds relative to the subordinate abundance of eclogite in the mantle lithosphere and the general absence of carbonate in mantle eclogite. This indicates carbon recycling at least to depths of diamond stability and may have represented a significant pathway for carbon ingassing through time.
DS1999-0365
1999
Heaman ...Kjarsgaard, B.J., Leckie, D.A., McNeil, D., Heaman ...Cretaceous kimberlite chaos? Fort a la Corne revisited and resolved8th. Calgary Mining forum, 2p. abstractSaskatchewanKimberlite, Deposit - Fort a la Corne
DS200712-1069
2007
Heamna, L.M.Tappe, S., Foley, S.F., Stracke, A., Romer, R.L., Kjarsgaard, B.A., Heamna, L.M., Joyce, N.Craton reactivation on the Labrador sea margins 40Ar 39Ar age and Sr Nd Hf Pb isotope constraints from alkaline and carbonatite intrusives.Earth and Planetary Science Letters, Vol. 256, 3-4, pp. 433-454.CanadaCarbonatite
DS1991-0693
1991
Hean, S.Hean, S.Environment and the economyThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Special Feature on environment, Vol. 84, No. 952, Augustpp. 52-54CanadaLegal -environment, Economics
DS200612-0363
2006
Heaney, P.JEaton-Magana, S., Post, J.E., Freitas, J.A., Klein, P.B., Walters, R.A., Heaney, P.J, Butler, J.E.Luminescence of the Hope diamond and other blue diamonds.GIA Gemological Research Conference abstract volume, Held August 26-27, p. 32. 1/2p.TechnologySpectroscopy
DS1998-0332
1998
Heaney, P.J.De, S., Heaney, P.J., Vincenzi, E.P., Hargraves, R.B.Microstructural comparison between natural polycrystalline diamond -carbonado and artificial..Ima 17th. Abstract Vol., p. A16. poster abstractBrazil, Central African RepublicCarbonado, Diamond synthesis
DS2001-0239
2001
Heaney, P.J.De, S., Heaney, P.J., Wang, J.Chemical heterogeneity in carbonado, an enigmatic polycrystalline diamondEarth and Plan. Sci. Letters, Vol. 185, No. 3-4, Feb. 28, pp. 315-30.Central African RepublicGeochemistry - carbonado, Cathodluminescence
DS2001-0465
2001
Heaney, P.J.Heaney, P.J., Vicenzi, E.P., Giannuzzi, L., Livi, K.J.T.Focused ion beam milling: a method of site specific sample extraction for microanalysis of Earth materials.American Mineralogist, Vol. 86, pp. 1094-99.GlobalMicroanalysis - TEM, FIB
DS2002-0690
2002
Heaney, P.J.Heaney, P.J., Vicenzi, E.P., Subarnakha, De.Microstructural distinctions between two polycrystalline diamond variatiesEos, American Geophysical Union, Spring Abstract Volume, Vol.83,19, 1p.Brazil, Central African RepublicDiamond - morphology, carbonado
DS2002-1664
2002
Heaney, P.J.Vicenzi, E.P., Heaney, P.J., Snyder, K.Radiation halos, a rare microstructure in diamonds from the Central African RepublicEos, American Geophysical Union, Spring Abstract Volume, Vol.83,19, 1p.Central African RepublicDiamond - morphology, carbonado
DS200412-0433
2004
Heaney, P.J.De, S., Heaney, P.J., Fei, Y., Vicenzi, E.P.Microstructural study of synthetic sintered diamond and comparsion with carbonado, a natural polycrstalline diamond.American Mineralogist, Vol. 89, 2-3, Feb. Mar. pp. 439-46.TechnologyDiamond morphology
DS200512-0412
2005
Heaney, P.J.Heaney, P.J., Vicenzi, E.P., De, S.Strange diamonds: the mysterious origins of carbonado and framesite.Elements, Vol. 1, 2, March pp. 85-90.South America, Brazilframesite, polycrystalline, mineralogy
DS200712-0283
2006
Heaney, P.J.Eaton-Magana, S., Post, J.E., Walters, R.A., Heaney, P.J., Butler, J.E.Fluoresence of fancy color natural diamonds.Gems & Gemology, 4th International Symposium abstracts, Fall 2006, p.131-2. abstract onlyTechnologyDiamond colour - UV radiation
DS200812-0309
2008
Heaney, P.J.Eaton-Magana, S., Post, J.E., Heaney, P.J., Frietas, J., Klein, P., Walters, R., Butler, J.E.Using phosphorescence as a fingerprint for the Hope and other blue diamonds.Geology, Vol. 36, 1, pp.TechnologyDiamond morphology
DS200812-0310
2007
Heaney, P.J.Eaton-Magana, S., Post, J.E., Heaney, P.J., Walters, R.A., Breeding, C.M., Butler, J.E.Fluorescence spectra of colored diamonds using a rapid, mobile spectrometer.Gems & Gemology, Vol. 43, 4, Winter pp. 332-351.TechnologyType 1 a diamonds
DS1998-0601
1998
Heaney, R.B.Heaney, R.B., Taylor, P.T.Microstructural observations of polycrystalline diamond: a contribution To the carbonado conundrum.Earth and Planetary Science Letters, Vol. 164, No.3-4, Dec.30, pp. 421-42.GlobalDiamond morphology, Carbonado
DS201112-0695
2011
Heap, M.J.Mollo, S., Vinciguerra, S., Lezzi, G., Iarocci, A., Scarlato, P., Heap, M.J., Dingwell, D.B.Volcanic edifice weakening via devolatization reactions.Geophysical Journal International, In press, availableMantleVolcanism - not specific to diamonds
DS201810-2375
2018
Heap, M.J.Ryan, A.G., Russell, J.K., Heap, M.J.Rapid solid state sintering in volcanic systems.American Mineralogist, MS #6714, 19p.Mantlevolcanism
DS1998-1050
1998
Hearherington, A.Mueller, P., Hearherington, A.The Wyoming Province and its place in the evolution of Precambrian NorthAmerica.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A46.WyomingTectonic, Lithoprobe
DS2002-0691
2002
Hearld TribuneHearld TribuneGemesis ready to shine. Diamond chambers could produce rough gems by Friday using a process invented in Russia and fine tuned in Sarasota ( USA).Hearld Tribune, Nov. 21, 2p.United StatesNews item
DS1988-0136
1988
Hearm, B.C.Collerson, K., Hearm, B.C., Macdonald, R.A., Upton, B.F., Park, J.G.Granulite xenoliths from the Bearpaw Mountains,Montana: constraints on the character and evolution of lower continental crustTerra Cognita, Eclogite conference, Vol. 8, No. 3, Summer, p. 270. AbstractMontanaXenoliths, Bearpaw Mountains
DS1987-0181
1987
Hearn, B.C.Eggler, D.H., Dudas, F.O., Hearn, B.C., McCallum, M.E., McGee, E.S.Lithosphere of the continental United States: Xenoliths in Kimberlites and other alkaline magmasin: Nixon, P.H. ed. Mantle xenoliths, J. Wiley, pp. 41-58United States, Montana, Colorado Wyoming, Kansas, Arkansas, MichiganTennessee, Kentucky, Pennsylvania, New York, Wyoming, Arizon
DS1992-0970
1992
Hearn, B.C.Macdonald, R., Upton, B.G.J., Collerson, K.D., Hearn, B.C.Potassic mafic lavas of the Bearpaw Mountains, Montana-mineralogy, chemistry and origin ( review)Journal of Petrology, Vol. 33, No. 2, April pp. 305-346MontanaPotassic magmatism, Bearpaw Mountains
DS201412-0179
2014
Hearn, B.C.Delpit, S., Ross, P-S., Hearn, B.C.Deep bedded ultramafic diatremes in the Missouri River breaks volcanic field, Montana, USA: 1 km of syn-eruptive subsidence.Bulletin of Volcanology, Vol. 76, p. 832-United States, MontanaMissouri Breaks diatreme
DS201504-0192
2014
Hearn, B.C.Delpit, S., Ross, P-S., Hearn, B.C.Deep bedded ultramafic diatremes in the Missouri River Breaks volcanic field, Montana, USA.Bulletin of Volcanology, Vol. 76, p. 832-United States, MontanaDiatreme
DS202111-1763
2021
Hearn, B.C.Chin, E.J., Chilson-Parks, B., Boneh, Y., Hirth, G., Saal, A.E., Hearn, B.C., Hauri, E.H.The peridotite deformation cycle in cratons and the deep impact of subduction.Tectonophysics, Vol. 817, 229029, 22p. PdfUnited States, Wyomingdeposit - Homestead, Williams

Abstract: Xenoliths play a crucial role in interpretation of mantle deformation and geochemistry. The classic work of Mercier and Nicolas (1975) introduced the concept of the peridotite deformation cycle, which connected observed microstructures to a physical sequence of deformation. We revisit Mercier and Nicolas' original concept, bringing in new constraints using large area EBSD maps and associated microstructural datasets, analysis of water contents in nominally anhydrous minerals, and trace element chemistry of pyroxenes and garnets. We apply these techniques to a well-characterized suite of peridotite xenoliths from the Eocene-age Homestead and Williams kimberlites in the northwestern Wyoming Craton. Pyroxene water content and trace element mineral chemistries reveal ubiquitous hydrous metasomatism beneath the craton, most likely linked to the Cenozoic Laramide Orogeny. Homestead xenoliths primarily exhibit coarse protogranular and equigranular textures, B-type olivine fabrics, and generally elevated mineral water contents compared to Williams. Xenoliths from Williams are strongly deformed, with porphyroclastic and transitional textures containing annealed olivine tablets, mostly A-type olivine fabrics, and generally lower mineral water contents. As a whole, mantle from Homestead to Williams reflects a cratonic scale deformation cycle that likely initiated in Laramide times and lasted until the end of orogeny in the Eocene. At Williams, evidence for a rapid deformation “sub-cycle” within the main deformation cycle is preserved in the tablet-bearing xenoliths, corresponding to the enigmatic “transitional” texture of Mercier and Nicolas (1975). Our results suggest that this texture reflects interruption of the main deformation cycle by processes possibly related to a rapidly forming lithospheric instability and generation of the kimberlite magma - offering a new interpretation of this ambiguous peridotite texture. Collectively, our results incorporate typically disparate geochemical and textural datasets on xenoliths to shed new insights into how metasomatism, volatiles, and deformation are connected in the deep cratonic lithosphere.
DS1982-0423
1982
Hearn, B.C. JR.Mcgee, E.S., Hearn, B.C. JR.Inclusions in the Lake Ellen Kimberlite, Northern Michigan, united States (us)Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 220, (abstract.).Michigan, United States, Great LakesKimberlite, Geophysics, Magnetic, Groundmag
DS1986-0353
1986
Hearn, B.C. Jr.Hearn, B.C. Jr.Alkalic ultramafic magmas in north central Montana, USA: genetic connections of alnoite, kimberlite and carbonatite #1Proceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, Geological, No. 16, pp. 33-35MontanaCarbonatite, Alkaline rocks
DS1986-0553
1986
Hearn, B.C. Jr.McGee, E.S., Hearn, B.C. Jr.Carbonates xenoliths from the Macdougal Springs mica peridotitediatreme:inferences for upper mantle conditions in north central MontanaProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 291-293MontanaBlank
DS1998-0602
1998
Hearn, B.C. Jr.Hearn, B.C. Jr.Peridotite xenoliths from Porcupine Dome, Montana: depleted subcontinental lithosphere samples ...7th International Kimberlite Conference Abstract, pp. 328-30.MontanaMagma - olivine phlogopite carbonate, Deposit - Porcupine Dome
DS201608-1438
2015
Hearn, B.C. Jr.Schulze, D.J., Hearn, B.C. Jr.Mantle xenocrysts from the Masontown, Pennsylvania kimberlite: an ordinary mantle with Si-enriched spinel.The Canadian Mineralogist, Vol. 53, pp. 767-773.United States, PennsylvaniaDike - Monongahela River

Abstract: A hypabyssal kimberlite dike in southwestern Pennsylvania (USA), emplaced through Proterozoic basement and Phanerozic cover, contains a xenocryst and xenolith assemblage typical of material sampled within the subcontinental lithosphere, including xenocrysts of Cr-rich pyrope, magnesiochromite, Cr-rich diopside, and peridotite xenoliths. Temperatures and depths of equilibration of the clinopyroxene (840 ºC and 130 km to 1350 ºC and 170 km) indicate some sampling in the field of diamond stability. Diamonds have not been reported, however, and the chemistry of the garnet (lherzolite, Cr-poor megacryst, and Group II eclogite) and spinel (<56.0 wt.% Cr2O3) are consistent with diamond absence and the off-craton tectonic setting of the kimberlite. An unusual feature of this suite is that, unlike most mantle xenolith/xenocryst spinel, some of those from Masontown have an unusually high silica content (to 0.59 wt.% SiO2). The significance of the high silica content is unclear, but may be related to an ultrahigh-pressure precursor chromite polymorph with a calcium ferrite structure, which can accommodate Si in solid solution.
DS1983-0299
1983
Hearn, B.C.JRHearn, B.C.JR, Mcgee, E.S.Garnets in Montana Diatremes; a Key to Prospecting for Kimberlites.United States Geological Survey (USGS) Bulletin., No. 1604, 33P.United States, Montana, Rocky MountainsMineral Chemistry, Inclusions, Microprobe, Analyses
DS1960-0839
1967
Hearn, B.C.JR.Hearn, B.C.JR.Montana Diatremes With Kimberlitic AffinitiesEos, Vol. 48, No. 1, P. 256, (abstract.).United States, Montana, Rocky MountainsDiatreme
DS1960-0961
1968
Hearn, B.C.JR.Hearn, B.C.JR.Diatremes with Kimberlitic Affinities in North Central Montana.Science., Vol. 159, No. 3815, PP. 622-625.United States, Montana, Rocky MountainsKimberlite
DS1970-0091
1970
Hearn, B.C.JR.Hearn, B.C.JR.Xenoliths of the Bearpaw Mountains. Eagle Buttes, and Missouri River Breaks Montana.Gsa Penrose Conference, Sahuaro Lake, Arizona, Catalogue Of, PP. 93-98.United States, Montana, Rocky MountainsXenoliths, Petrography
DS1970-0712
1973
Hearn, B.C.JR.Hearn, B.C.JR., Boyd, F.R.Garnet Peridotite Xenoliths in a Montana Kimberlite. #1International Kimberlite Conference FIRST, EXTENDED ABSTRACT VOLUME., PP. 167-169.United States, Montana, Rocky MountainsKimberlite, Rocky Mountains
DS1975-0102
1975
Hearn, B.C.JR.Hearn, B.C.JR., Boyd, F.R.Garnet Peridotite Xenoliths in a Montana Kimberlite. #2Physics Chem. Earth., Vol. 9, PP. 247-256.United States, Montana, Rocky MountainsBlank
DS1975-0292
1976
Hearn, B.C.JR.Hearn, B.C.JR.Geologic and Tectonic Maps of the Bearpaw Mountains Area North Central Montana.United States Geological Survey (USGS) miscellaneous INV., MAP No. MI 919, 1:125, 000.United States, Montana, Rocky MountainsGeology, Tectonics
DS1975-1069
1979
Hearn, B.C.JR.Hearn, B.C.JR.Preliminary Map of Diatremes and Alkalic Ultramafic Intrusions in the Missouri River Breaks Vicinity, North Central Montana.United States Geological Survey (USGS) OPEN FILE REPORT., No. 79-128.United States, Montana, Rocky MountainsBlank
DS1980-0168
1980
Hearn, B.C.JR.Hearn, B.C.JR.Geology of the Williams Kimberlite Diatremes, North Centralmontana.Geological Society of America (GSA), Vol. 12, No. 6, MARCH P. 274. (abstract.).United States, Montana, Rocky MountainsBlank
DS1980-0229
1980
Hearn, B.C.JR.Mcgee, E.S., Hearn, B.C.JR.Garnets as Tracer Minerals for Montana KimberlitesGeological Society of America (GSA), Vol. 12, No. 6, P. 280, (abstract.).MontanaKimberlite, Rocky Mountains
DS1981-0210
1981
Hearn, B.C.JR.Hearn, B.C.JR.Diamond Potential of Missouri Breaks Diatremes, MontanaUnited States Geological Survey (USGS) PROF. PAPER., No. 1175, P. 4, (abstract.).United States, Montana, Rocky MountainsBlank
DS1981-0211
1981
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from the Williams Kimberlites, North Central Montana.Geological Society of America (GSA), Vol. 13, No. 4, P. 199, (abstract.).United States, Montana, Rocky MountainsBlank
DS1982-0267
1982
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from Williams Kimberlites, North-centralmontana, United States (us)Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 218, (abstract.).United States, Montana, Rocky MountainsKimberlite, Alnoite, Diatreme, Lherzolite, Harzburgite, Dunite
DS1982-0268
1982
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Garnet in Montana Diatremes: a Key to Prospecting for Kimberlites.United States Geological Survey (USGS) OPEN FILE REPORT., No. 82-722, 45P.United States, Montana, Rocky MountainsKimberlite, Analyses, Williams, Big Slide, Bulletinwacker Coulee
DS1983-0300
1983
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotites from Williams Kimberlites, North Centralmontana, United States (us)United States Geological Survey (USGS) OPEN FILE., No. 83-172, 26P.United States, Montana, Rocky MountainsAlnoite, Xenoliths, Petrography, Lherzolite, Geology, Diatreme
DS1983-0441
1983
Hearn, B.C.JR.Mcgee, E.S., Hearn, B.C.JR.Lake Ellen Kimberlite, Michigan, United States (us)United States Geological Survey (USGS) OPEN FILE., No. 83-156, 22P.United States, Michigan, Great LakesXenolith, Megacrysts, Petrology, Petrography, Inclusions, Kimberite
DS1984-0351
1984
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Garnet Peridotite from Williams Kimberlites, North Central Montana, United States (us)Proceedings of Third International Kimberlite Conference, Vol. 2, PP. 57-70.United States, Rocky Mountains, MontanaInclusions, Textures, Petrography, Mineral Chemistry, Analyses
DS1984-0503
1984
Hearn, B.C.JR.Mcgee, E.S., Hearn, B.C.JR.The Lake Ellen Kimberlite, Michigan, United States (us)Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 143-154.United States, Michigan, Great LakesProspecting, History, Xenocrysts, Mineralogy, Analyses, Inclusion
DS1985-0276
1985
Hearn, B.C.JR.Hearn, B.C.JR.Alkalic Ultramafic Magmas, Missouri Breaks, Montana: the Kimberlite-alnoite Continuum.Geological Society of America (GSA), Vol. 17, No. 3, P. 161. (abstract.).United States, Montana, Rocky MountainsBlank
DS1985-0277
1985
Hearn, B.C.JR.Hearn, B.C.JR., Mcgee, E.S.Research on Kimberlites and Applications to Diamond Prospecting.United States Geological Survey (USGS) INF. Circular, No. 949, PP. 22-23.United States, Montana, Michigan, Colorado, Great Lakes, Rocky MountainsCurrent Review
DS1989-0607
1989
Hearn, B.C.Jr.Hearn, B.C.Jr.Alkalic ultramafic magmas in north central Montana, USA: genetic connections of alnoite, kimberlite and carbonatite #2Geological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 109-119MontanaAlnoite, Kimberlite
DS1989-0608
1989
Hearn, B.C.Jr.Hearn, B.C.Jr., Collerson, K.D., MacDonald, R.A., Upton, B.G.J.Mantle crustal lithosphere of north central Montana,USA: evidence fromxenolithsNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 125. AbstractMontanaXenoliths
DS1989-0609
1989
Hearn, B.C.Jr.Hearn, B.C.Jr., Dudas, F.O., Eggler, D.H., Hyndman, D.W. , O'BrienMontana high pressureotassium igneous province. Crazy Mountains to Montana. July 20-27American Geophysical Union (AGU) 28th. International Geological Congress Field Trip Guidebook, No. T 346, 86pMontanaHighwood Mountains, Minettes, Shonkinites, Lamproites
DS1989-0984
1989
Hearn, B.C.Jr.McGee, E.S., Hearn, B.C.Jr.Primary and secondary mineralogy of carbonated peridotites from the Macdougal Springs diatremeGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 725-734MontanaMineralogy, Peridotite
DS1991-0694
1991
Hearn, B.C.Jr.Hearn, B.C.Jr., Collerson, K.D., Upton, B.G.J., Macdonald, R.A.Ancient enriched upper mantle beneath north-central Montana: evidence fromxenolithsGuidebook of the Central Montana Alkalic Province, ed. Baker, D.W., Berg. R., No. 100, pp. 133-135. extended abstractMontanaMantle, xenoliths
DS1993-0721
1993
Hearn, B.C.Jr.Irving, A.J., Carlson, R.W., Hearn, B.C.Jr.Differentiation history of lithospheric mantle: Osmium, Strontium, neodymium and lead isotopic evidence from garnet peridotite xenoliths, Williams kimberlite, MontanaEos, Transactions, American Geophysical Union, Vol. 74, No. 16, April 20, supplement abstract p. 320MontanaGeochronology
DS1994-0749
1994
Hearn, B.C.Jr.Hearn, B.C.Jr.Composite megacrysts and megacryst aggregates from the Williamskimberlites, Montana, USA: multiple products of mantle melts. #2Proceedings of Fifth International Kimberlite Conference, Vol. 1, pp. 388-404.MontanaMegacrysts, Deposit -Williams
DS1998-0214
1998
Hearn, B.C.Jr.Carlson, R.W., Irving, A.J., Hearn, B.C.Jr.Peridotite xenoliths from the William kimberlite, Montana: implications for delamination Wyoming Craton7th International Kimberlite Conference Abstract, pp. 132-4.MontanaLithosphere - geochronology, Deposit - WilliaM.
DS201412-0213
2014
Hearn, B.C.Jr.Duke, G.I., Carlson, R.W., Frost, C.D., Hearn, B.C.Jr., Eby, G.N.Continental scale linearity of kimberlite-carbonatite magmatism, mid-continent North America.Earth and Planetary Science Letters, Vol. 403, pp. 157-163.Canada, United StatesLineaments
DS1987-0351
1987
Hearn, B.C.Jr.He YongnianKirby, S.H., Hearn, B.C.Jr.He Yongnian, Lin ChuangyongGeophysical implications of mantle xenoliths ; evidence for fault zones In the deep lithosphere of eastern ChinaUnited States Geological Survey (USGS) Circular No. 956 Geophysics and petrology of the deep crust and, pp. 63-65ChinaLineaments
DS200712-1141
2007
Hearn, E.H.Welford, J.K., Hearn, E.H., Clowes, R.M.Possible role of midcrustal igneous sheet intrusions in cratonic arch formation.Tectonics, Vol. 26, 11p.United States, CanadaCratonic arches
DS2003-0215
2003
Hearn, Jr. B.C.Carlson, R.W., Irving, A.J., Schulze, D.J., Hearn, Jr. B.C.Timing of lithospheric mantle modification beneath the Wyoming Craton8 Ikc Www.venuewest.com/8ikc/program.htm, Session 4, AbstractColorado, MontanaMantle geochemistry, Geochronology, Sloan, Homestead, Williams
DS2003-0571
2003
Hearn, Jr. B.C.Hearn, Jr. B.C.Upper mantle xenoliths in the Homestead kimberlite central Montana, USA: depleted8 Ikc Www.venuewest.com/8ikc/program.htm, Session 6, POSTER abstractMontanaDeposit - Homestead
DS200412-0279
2003
Hearn, Jr.B.C.Carlson, R.W., Irving, A.J., Schulze, D.J., Hearn, Jr.B.C.Timing of lithospheric mantle modification beneath the Wyoming Craton.8 IKC Program, Session 4, AbstractUnited States, Colorado, MontanaMantle geochemistry Geochronology, Sloan, Homestead, Williams
DS200412-0813
2003
Hearn, Jr.B.C.Hearn, Jr.B.C.Upper mantle xenoliths in the Homestead kimberlite central Montana, USA: depleted and re enriched Wyoming craton samples.8 IKC Program, Session 6, POSTER abstractUnited States, MontanaMantle petrology Deposit - Homestead
DS1991-0695
1991
Hearn, T.Hearn, T., Beghoul, N., Barazangi, M.Tomography of the western United States from regional arrival timesJournal of Geophysical Research, Vol. 96, No. B 10, September 10, pp. 16, 369-16, 381Basin and Range, CordilleraCrust -thickness, Geophysics -seismics
DS1999-0726
1999
Hearn, T.Tandon, K., Brown., L., Hearn, T.Deep structure of the northern Rio Grande rift beneath the San Luis basin (Colorado) from a seismic surveyTectonophysics, Vol. 302, No. 1-2, Feb. 15, pp. 41-56.ColoradoTectonics, rift evolution
DS1991-1375
1991
Hearn, T.M.Pratt, T.L., Hauser, E.C., Hearn, T.M., Reston, T.J.Reflection polarity of the Midcrustal Surrency bright spot beneath southeastern Georgia. Testing the fluid hypothesisJournal of Geophysical Research, Vol. 96, No. B6, June 10, pp. 10, 145-10, 158GeorgiaGeophysics, Tectonics
DS200512-0413
2004
Hearn, T.M.Hearn, T.M., Wang, S., Ni, J.F., Xu, Z., Yu,Y., Zhang, X.Uppermost mantle velocities beneath Chin a and surrounding regions.Journal of Geophysical Research, Vol. 109, 11, DOI 10:1029/2003 JB002874ChinaGeophysics - seismics
DS1991-0696
1991
Hearne, B.C.Jr.Hearne, B.C.Jr.Composite megacrysts and megacryst aggregates from the Williamskimberlites, Montana, United States (US): multiple products of mantle melts #1Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 170-172MontanaWillams, kimberlites, Geochemistry
DS2003-0206
2003
Hearne, B.J.Jr.Canil, D., Schulze, D.J., Hall, D., Hearne, B.J.Jr., Milliken, S.M.Lithospheric roots beneath western Laurentia: the geochemical signal in mantle garnetsCanadian Journal of Earth Sciences, Vol. 40, 8, Aug. pp. 1027-51.Wyoming, British ColumbiaTectonics,geochemistry, geochronology, Ni thermometry
DS200412-0266
2003
Hearne, B.J.Jr.Canil, D., Schulze, D.J., Hall, D., Hearne, B.J.Jr., Milliken, S.M.Lithospheric roots beneath western Laurentia: the geochemical signal in mantle garnets.Canadian Journal of Earth Sciences, Vol. 40, 8, Aug. pp. 1027-51.United States, WyomingTectonics,geochemistry, geochronology, Ni thermometry
DS1991-0697
1991
Hearne, S.C.Hearne, S.C.Geology of the Montana diatremesConference registration The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Xerox Tower Suite 1210, 3400 de Maissoneuve, Sept. 5-13, 1991 Fax 514 939-2714MontanaDiatremes, Alkaline rocks
DS1987-0286
1987
Hearns, B.C.Jr.Hearns, B.C.Jr., McGee, E.S.Crust and upper mantle beneath the Northern Plains; evidence from MontanaxenolithsUnited States Geological Survey (USGS) Circular No.956 Geophysics and petrology of the deep crust and upper, pp. 32-34MontanaXenoliths
DS2000-0969
2000
Hearns, P.USGS, Hearns, P., Hare, Schruber, Sherrill, LaMarGlobal GIS database: digital atlas of Central and South AmericaUsgs, DDS-62-A ( CD ROM)Central America, South AmericaDigital Data series - atlas
DS1994-0750
1994
Hearst, R.Hearst, R., Morris, W., Thomas, M.Magnetic interpretation along the Sudbury structure -Lithoprobe transectGeophy. Res. Letters, Vol. 21, No. 10, May 15, pp. 951-954OntarioLithoprobe, Sudbury Structure
DS2002-0692
2002
Hearts on FireHearts on FireA milestone advertising campaign in the world of branded diamonds: Hearts on Fire national WOW campaign building its brand through local partnerships.Hearts on Fire, Nov. 25, 1p.MassachusettsPress release, diamond synthesis
DS1981-0212
1981
Heasler, H.P.Heasler, H.P.A Summary of Geothermal Potential and Development in WyomingThe Interstate Oil Compact Comm. Committee Bulletin., Vol. 23, No. 1, PP. 18-26.United States, Wyoming, Rocky MountainsBlank
DS1997-0497
1997
Heasley, D.Heasley, D.Indigineous people are part of environmental protectionMining Engineering, Vol. 49, No. 11, Nov. pp. 20-21GlobalAboriginal, Native - claims
DS2002-0693
2002
Heath, C.P.M.Heath, C.P.M.Technical, non-technical and other skills needed by Canadian Mining, Petroleum, Public Sector organizationsGeoscience Canada, Vol.29,1,March pp. 21-34.CanadaMining - skill profile
DS1960-0557
1965
Heath, D.C.Heath, D.C., Toerien, D.K.A Cryptovolcanic Structure on Hatzium Ii. 28, Southwest Africa.Geological Survey of South Africa Annual Report, Vol. 1, PP. 81-85.Southwest Africa, NamibiaGeology, Hatzium Dome
DS1988-0296
1988
Heath, K.C.G.Heath, K.C.G.Mine costing... remarks on a previously published paperTransactions of the Institute of Mining and Metallurgy (IMM), Vol. 97, October pp. A 196-197. Database # 17539ZambiaGeostatistics, Costs-mining
DS200612-0557
2005
Heath, P.J.Heath, P.J., Greenhalgh, S., Direen, N.G.Modeling gravity and magnetic gradient tensor responses for exploration within the regolith.Exploration Geophysics, Vol. 36, 4, pp. 357-364.AustraliaGeophysics - not specific to diamonds
DS1975-1138
1979
Heathcote, R.Mccormick, G., Heathcote, R.Mineralogy of the Morrilton Alvikite Dike, Conway County, ArkansasGeological Society of America (GSA), Vol. 11, P. 163. (abstract.).United States, Gulf Coast, Arkansas, Conway CountyBlank
DS1970-0925
1974
Heathcote, R.C.Heathcote, R.C.Fenitization of the Arkansaw Novaculite and Adjacent Intrusive, Garland County, Arkansaw.M.s. Thesis, University Arkansaw, 56P.United States, Gulf Coast, Arkansas, Garland CountyAlteration
DS1975-0293
1976
Heathcote, R.C.Heathcote, R.C.Fenitization of the Arkansaw Novaculite, Garland County, Arkansas.Geological Society of America (GSA), Vol. 8, No. 6, P. 910. (abstract.).United States, Gulf Coast, Arkansas, Garland CountyAlteration
DS1975-1070
1979
Heathcote, R.C.Heathcote, R.C.Temporal Relationships of Carbonatite and Fenite at Potash Sulfur Springs, Arkansaw.Geological Society of America (GSA), Vol. 11, No. 2, PP. 148-149. (abstract.).United States, Gulf Coast, Arkansas, Garland CountyPetrology
DS1981-0213
1981
Heathcote, R.C.Heathcote, R.C., Owens, D.R.Formation of Vanadium at Potash Sulfur Springs, ArkansawGeological Society of America (GSA), Vol. 13, No. 7, P. 470. (abstract.).United States, Gulf Coast, Arkansas, Garland CountyVanadium
DS1987-0287
1987
Heathcote, R.C.Heathcote, R.C.Mica compositions and carbonatite petrogenesis in the potash Sulfur Springs intrusive complex, Garland County, ArkansawPhd. Thesis, University of Iowa, Iowa City, Iowa, 144pArkansasBlank
DS1987-0452
1987
Heathcote, R.C.McCormick, G.R., Heathcote, R.C.Mineral chemistry and petrogenesis of carbonatite intrusions, Perry and Conway Counties, ArkansawAmerican Mineralogist, Vol. 72, No. 1-2, Jan-Feb. pp. 59-66ArkansasUSA, Carbonatite
DS1989-0610
1989
Heathcote, R.C.Heathcote, R.C., McCormick, G.R.Major-cation substitution in phlogopite and evolution of carbonatite In the Potash Sulfur Springs complex, Garland County, ArkansawAmerican Mineralogist, Vol. 74, No. 1-2, January-February pp. 132-140ArkansasAnalyses: Clinopyroxenes, phlogopite
DS1991-1489
1991
Heather, K.B.Sage, R.P., Heather, K.B.The structure, stratigraphy and mineral deposits of the Wawa areaGeological Association of Canada (GAC) Annual Meeting held Toronto May 1991, Guidebook, No. A6, 38pOntarioGeology, Wawa, Structure, Iron
DS2002-1104
2002
HeatheringtonMueller, P.A., Heatherington, Kelly, Wooden, MogkPaleoproterozoic crust within the Great Falls tectonic zone: implications for assembly of southern Laurentia.Geology, Vol. 30, No. 2, Feb. pp. 127-30.MontanaTectonics, Archean Hearne, Wyoming
DS1987-0288
1987
Heatherington, A.Heatherington, A., Bowring, S.A., Luhr, J.Petrogenesis of calc-alkaline and alkaline volcanics from the western Mexican volcanic belt PB-isotopesGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p.698. abstracMexicoMinette
DS1996-1001
1996
Heatherington, A.Mueller, P.A., Heatherington, A.Proterozoic evolution of the Northwestern Wyoming CratonGeological Society of America, Abstracts, Vol. 28, No. 7, p. A-314.WyomingTectonics, Geochronology
DS2002-0473
2002
Heatherington, A.Foster, D.A., Mueller, P.A., Heatherington, A., Vogl, J., Meert, J., Lewis, R.Configuration of the 2.0 - 1.6 GA accretionary margin NW of the Wyoming Province:Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 559.WyomingTectonics, Gondwana
DS1994-1249
1994
Heatherington, A.L.Mueller, P.A., Heatherington, A.L., Wooden, J.L., et al.Precambrian zircons from the Florida basement: a Gondwanan connectionGeology, Vol. 22, No. 2, Feberuary pp. 119-122GlobalGondwana, Geochronology
DS1996-1002
1996
Heatherington, A.L.Mueller, P.A., Heatherington, A.L., Nutman, A.P.Contrasts between samarium-neodymium (Sm-Nd) whole rock and uranium-lead (U-Pb) zircon systematics in the Tobacco Root batholith, Montana..Tectonophysics, Vol. 265, No. 1/2, Nov. 15, pp. 169-180MontanaGeochronology, Crustal age provinces
DS1996-1003
1996
Heatherington, A.L.Mueller, P.A., Heatherington, A.L., Nutman, A.P.Contrasts between samarium-neodymium (Sm-Nd) whole rock and uranium-lead (U-Pb) (U-Pb) zircon systematics in the Tobacco Root batholith, MontanaTectonophysics, Vol. 265, No. 1/2, Nov. 5, pp. 169-180.MontanaGeochronology, Crustal age Provinces
DS1975-0494
1977
Heatherington, E.A.Denison, R.E., Burke, W.H., Otto, J.B., Heatherington, E.A.Age of Igneous and Metamorphic Activity Affecting the Ouachita Foldbelt.Arkansaw GEOL. COMM., PP. 25-40.United States, Oklahoma, ArkansasStructure, Geochronology
DS201609-1707
2016
Heaton, T.Broom-Fendley, S., Heaton, T., Wall, F., Gunn, G.Tracing the fluid source of heavy REE mineralization in carbonatites using a novel method of oxygen isotope analysis in apatite: the example of Songwe Hill, Malawi.Chemical Geology, Vol. 440, pp. 275-287.Africa, MalawiCarbonatite

Abstract: Stable (C and O) isotope data from carbonates are one of the most important methods used to infer genetic processes in carbonatites. However despite their ubiquitous use in geological studies, it is suspected that carbonates are susceptible to dissolution-reprecipitation and isotopic resetting, especially in shallow intrusions, and may not be the best records of either igneous or hydrothermal processes. Apatite, however, should be much less susceptible to these resetting problems but has not been used for O isotope analysis. In this contribution, a novel bulk-carbonatite method for the analysis of O isotopes in the apatite PO4 site demonstrates a more robust record of stable isotope values. Analyses of apatite from five carbonatites with magmatic textures establishes a preliminary Primary Igneous Apatite (PIA) field of ?18O = + 2.5 to + 6.0‰ (VSMOW), comparable to Primary Igneous Carbonatite (PIC) compositions from carbonates. Carbonate and apatite stable isotope data are compared in 10 carbonatite samples from Songwe Hill, Malawi. Apatite is heavy rare earth element (HREE) enriched at Songwe and, therefore, oxygen isotope analyses of this mineral are ideal for understanding HREE-related mineralisation in carbonatites. Carbonate C and O isotope ratios show a general trend, from early to late in the evolution, towards higher ?18O values (+ 7.8 to + 26.7‰, VSMOW), with a slight increase in ?13C (? 4.6 to ? 0.1‰, VPDB). Oxygen isotope ratios from apatite show a contrary trend, decreasing from a PIA field towards more negative values (+ 2.5 to ? 0.7‰, VSMOW). The contrasting results are interpreted as the product of the different minerals recording fluid interaction at different temperatures and compositions. Modelling indicates the possibility of both a CO2 rich fluid and mixing between meteoric and deuteric waters. A model is proposed where brecciation leads to depressurisation and rapid apatite precipitation. Subsequently, a convection cell develops from a carbonatite, interacting with surrounding meteoric water. REE are likely to be transported in this convection cell and precipitate owing to decreasing salinity and/or temperature.
DS200412-0221
2004
Heber, V.S.Brooker, R.A., Heber, V.S., Kelly, S.P., Wood, B.J.Noble gas partitioning during mantle melting: possible retention of He & Ar relative to U, Th & K.Lithos, ABSTRACTS only, Vol. 73, p. S15. abstractMantleMelting
DS201701-0026
2016
Hebert, C.Piet, H., Badro, J., Nabiel, F., Dennenwaldt, T., Shim, S-H., Cantoni, M., Hebert, C., Gillet, P.Spin and valence dependence on iron partitioning in Earth's deep mantle.Proceedings of National Academy of Science USA, Vol. 113, no. 40, pp. 11127-11130.MantleUHP

Abstract: We performed laser-heated diamond anvil cell experiments combined with state-of-the-art electron microanalysis (focused ion beam and aberration-corrected transmission electron microscopy) to study the distribution and valence of iron in Earth's lower mantle as a function of depth and composition. Our data reconcile the apparently discrepant existing dataset, by clarifying the effects of spin (high/low) and valence (ferrous/ferric) states on iron partitioning in the deep mantle. In aluminum-bearing compositions relevant to Earth's mantle, iron concentration in silicates drops above 70 GPa before increasing up to 110 GPa with a minimum at 85 GPa; it then dramatically drops in the postperovskite stability field above 116 GPa. This compositional variation should strengthen the lowermost mantle between 1,800 km depth and 2,000 km depth, and weaken it between 2,000 km depth and the D" layer. The succession of layers could dynamically decouple the mantle above 2,000 km from the lowermost mantle, and provide a rheological basis for the stabilization and nonentrainment of large low-shear-velocity provinces below that depth.
DS201805-0964
2018
Hebert, C.Nabiel, F., Badro, J., Dennenwaldt, T., Oveisi, E., Cantoni, M., Hebert, C., El Goresy, A., Barrat, J-A., Gillet, P.A large planetary body inferred from diamond inclusions in a urelite metorite.Nature Communications, doe:10.1038/ s41467-018- 030808-6 6p. PdfTechnologyureilite

Abstract: Planetary formation models show that terrestrial planets are formed by the accretion of tens of Moon- to Mars-sized planetary embryos through energetic giant impacts. However, relics of these large proto-planets are yet to be found. Ureilites are one of the main families of achondritic meteorites and their parent body is believed to have been catastrophically disrupted by an impact during the first 10 million years of the solar system. Here we studied a section of the Almahata Sitta ureilite using transmission electron microscopy, where large diamonds were formed at high pressure inside the parent body. We discovered chromite, phosphate, and (Fe,Ni)-sulfide inclusions embedded in diamond. The composition and morphology of the inclusions can only be explained if the formation pressure was higher than 20?GPa. Such pressures suggest that the ureilite parent body was a Mercury- to Mars-sized planetary embryo.
DS200912-0291
2009
Hebert, L.B.Hebert, L.B., Antoshechkina, P., Asimow, P., Gurnis, M.Emergence of low viscosity channel in subduction zones through the coupling of mantle flow and thermodynamics.Earth and Planetary Interiors, Vol. 278, 3-4, pp. 243-256.MantleSubduction
DS1997-0402
1997
Hebert, R.Giguere, E., Hebert, R., Sharma, K.N.M., Cimon, J.Les peridotites grenvilliennes de l'Ouest du Quebec et leur potentiel diamantifere.Quebec Department of Mines, DV 97-03, p. 39.QuebecExploration - assessment
DS1998-0507
1998
Hebert, R.Giguere, E., Hebert, R., Sharma, K.N.M., Cimon, J.Les roches ultramafiques de la region de Temiscamingue et Fort CoulongeQuebec Department of Mines, DV 98-05, p. 41.QuebecExploration - assessment
DS1998-1038
1998
Hebert, R.Morin, D., Corriveau, L., Hebert, R.Magmatic suites underplating the southern Grenville Province: ultramafic xenoliths of 1.07 Ga Rivard dyke.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Abstract Volume, p. A127. abstract.QuebecMinette, Xenolith - petrography
DS1980-0169
1980
Hebert, S.Hebert, S.Diamonds 1980East Sussex: Wayland World Resources Series, 72P.South Africa, GlobalKimberley, Mineral Resources
DS201801-0022
2017
Hecht, H.Hecht, H., Oguchi, T.Global evalusation of erosion rates in relation to tectonics. Progress in Earth and Planetary Science, 7p. PdfGlobaltectonics

Abstract: Understanding the mechanisms and controlling factors of erosion rates is essential in order to sufficiently comprehend bigger processes such as landscape evolution. For decades, scientists have been researching erosion rates where one of the main objectives was to find the controlling factors. A variety of parameters have been suggested ranging from climate-related, basin morphometry and the tectonic setting of an area. This study focuses on the latter. We use previously published erosion rate data obtained mainly using 10Be and sediment yield and sediment yield data published by the United States Geological Survey. We correlate these data to tectonic-related factors, i.e., distance to tectonic plate boundary, peak ground acceleration (PGA), and fault distribution. We also examine the relationship between erosion rate and mean basin slope and find significant correlations of erosion rates with distance to tectonic plate boundary, PGA, and slope. The data are binned into high, medium, and low values of each of these parameters and grouped in all combinations. We find that groups with a combination of high PGA (>?0.2.86 g) and long distance (>?1118.69 km) or low PGA (
DS1986-0354
1986
Hecht, J.Hecht, J.The chemical vapor that grows diamonds. (Editorial)New Scientist, Vol. 112, No. 1529, October 9, p. 28. (abstract.)GlobalDiamond morphology
DS1994-0751
1994
Hecht, J.Hecht, J.Buckyballs add polish to diamond filmsNew Scientist, July 30, p. 20.GlobalCVD diamond filM.
DS201212-0364
2012
Hecht, L.Koeberl, C., Claeys, P., Hecht, L., McDonald, I.Geochemistry of impactites.Elements, Vol. 8, 1, Feb. pp. 37-42.TechnologyPGM, isotopes
DS1989-0611
1989
Heck, F.R.Heck, F.R.Mesozoic extension in the southern AppalachiansGeology, Vol. 17, No. 8, August pp. 711-714AppalachiaTectonics, Rifts
DS1991-0319
1991
Hecker, B.Crane, K., Hecker, B., Golubev, V.Heat flow and hydrothermal vents in Lake Baikal, U.S.S.REos Transactions, Vol. 72, No. 52, December 24, pp. 585, 588RussiaTectonics, Rifting
DS202007-1145
2020
Hecker, J.G.Hecker, J.G., Marks, M.A.W., Wenzel, T., Markl, G.Halogens in amphibole and mica from mantle xenoliths: implications for the halogen distribution and halogen budget of the metasomatized continental lithosphere.American Mineralogist, Vol. 105, pp. 781-794.Mantlemetasomatism

Abstract: This study reports halogen contents (F and Cl) of amphibole and phlogopite derived from mantle xenoliths and one peridotite massif, for amphibole and phlogopite megacrysts and ultramafic magmatic cumulates (hornblendites) found in alkaline volcanic rocks from 12 localities in Europe and Africa. Amphibole and phlogopite contain more F than Cl with F/Cl ratios reaching about 160 in phlogopites and 50 in amphiboles. Phlogopites are higher in F (median of 3400 ?g/g) than amphibole (median of 1000 ?g/g), while median Cl contents are higher in amphibole (290 ?g/g) compared to phlogopite (180 ?g/g). The Cl contents and the F/Cl ratios in amphibole and phlogopite from mantle xenoliths exhibit large differences between samples of the same region, recording very large variations of halogen contents in the continental lithosphere. We suggest that the halogen content in such samples largely depends on the initial composition of percolating melts and fluids in the continental lithosphere. During reaction of these agents with peridotitic wall-rocks, Cl is preferentially retained in the fluid as it is much more incompatible compared to water and F. This desiccation effect continuously increases salinity (Cl content) and decreases the F/Cl ratio in the agent with time, causing variable Cl contents and F/Cl ratios in amphibole and phlogopite at a specific locality. Subsequent partial melting processes may then sequester and re-distribute, especially Cl among amphibole, phlogopite and melts/fluids as a result of its strong incompatibility, whereas F is much less affected as it behaves slightly compatible. The impact of even small amounts of amphibole and mica on the total halogen budget in the continental lithosphere is significant and both minerals can effectively contribute to the high halogen contents typical of alkaline melts.
DS1992-0692
1992
Hedenquist, J.W.Hedenquist, J.W.Magmatic contributions to hydrothermal systems and the behavior of volatiles in magmaJapan Geological Survey, Report No. 279, 200pMantleMagmatism, Volatiles
DS1999-0488
1999
Hedenquist, J.W.Molnar, F., Lexa, J., Hedenquist, J.W.Eoithermal mineralization of the Western CarpathiansSociety of Economic Geologists Guidebook, Vol. 31, 260p.Hungary, SlovakiaBook - table of contents, Gold, metallogeny
DS201712-2674
2017
Hedenquist, J.W.Arndt, N.T., Fontbote, L., Hedenquist, J.W., Kesler, S.E., Thompson, J. F.H., Wood, D.G.Future Global and Mineral Resources.geochemicalperspectives.org, Vol. 6, 1, April, 187p. Pdf 28 MBGlobalgeochemistry

Abstract: Some scientists and journalists, and many members of the general public, have been led to believe that the world is rapidly running out of the metals on which our modern society is based. Advocates of the peak metal concept have predicted for many decades that increasing consumption will soon lead to exhaustion of mineral resources. Yet, despite ever-increasing production and consumption, supplies of minerals have continued to meet the needs of industry and society, and lifetimes of reserves remain similar to what they were 30-40 years ago. In this volume, we discuss the reasons for this apparent paradox using our broad experience and expertise on both academic and industrial sides of the minerals sector. Many misconceptions arise from flawed estimates of the size of global mineral resources which stem from a lack of understanding of the critical difference between reserves and resources. Some authors use quoted reserves – the amount of metal proven to exist and to be economic for mining at present – when predicting imminent shortages. Resources – the amount that may be accessible in the upper few kilometres of the crust – are far larger.Over the last 150 years, improved technologies, economies of scale and increased efficiency have combined to reduce costs hence allowing lower-grade ore to be mined economically. The net result is that the long-term inflation-adjusted price of most metals has decreased more or less in parallel with increasing production, a second apparent paradox that frequently is not well understood. Using copper as the principal example and other metals as appropriate, we summarise the latest research on ore deposits and the activities of the minerals industry. Following a description of the numerous geological processes that form ore deposits, we outline the scientific methods used by the minerals industry to explore for new deposits. We also discuss how resources are mined and how minerals are processed, as well as recent efforts to reduce related environmental impacts. Economic and societal factors influence supply, and these are as important as the actual presence of a resource. Finally, we discuss the critical roles that geoscientists will play in assuring continued supplies of minerals. These include the development of new concepts and techniques that will assist the discovery, mining, processing, remediation, and management of mineral resources. It is essential that researchers help to educate the general public about the need for continued exploration to find new resources to meet growth in world living standards. We demonstrate that global resources of copper, and probably of most other metals, are much larger than most currently available estimates, especially if increasing efficiencies and higher prices allow lower-grade ores to be mined. These observations indicate that supplies of important mineral commodities will remain adequate for the foreseeable future.
DS1960-0669
1966
Hedge, C.E.Goldich, S.S., Lidiak, E.G., Hedge, C.E., Wathall, F.G.Geochronology of the Midcontinent Region, United States. Pt. 2. Northern Area.Journal of GEOPHYSICAL RESEARCH, Vol. 71, No. 22, PP. 5389-5408.GlobalMid-continent
DS1960-0670
1966
Hedge, C.E.Goldich, S.S., Muehlberger, W.R., Kidiak, E.G., Hedge, C.E.Geochronology of the Midcontinent Region, United States. Pt. 4: Eastern Area.Journal of GEOPHYSICAL RESEARCH, Vol. 71, No. 22, PP. 5375-5388.GlobalMid-continent
DS1960-0713
1966
Hedge, C.E.Muehlberger, W.R., Hedge, C.E., Denison, R.E., Marvin, R.F.Geochronology of the Midcontinent Region, United States. Pt. 3, Southern Area.Journal of GEOPHYSICAL RESEARCH, Vol. 71, PP. 5409-5426.GlobalMid-continent
DS1960-1008
1968
Hedge, C.E.Peterman, Z.E., Hedge, C.E., Braddock, W.A.Age of Precambrian Events in the Northeast Front Range, Colorado.Journal of Geophysical Research, Vol. 73, PP. 2277-2296.United States, Colorado, State Line, Rocky MountainsDiatreme
DS1975-0336
1976
Hedge, C.E.Mccallum, M.E., Hedge, C.E.Rubidium-strontium Ages of Granitic Rocks in the Rawah Batholith, medicine Bow Mountains, Northern Colorado.Isochron West., No. 17, PP. 33-37.United States, State Line, Colorado, WyomingGeochronology, Batholites
DS1982-0072
1982
Hedge, C.E.Armbrustmacher, T.J., Hedge, C.E.Genetic implications of minor element and Strontium isotope geochemistry of alkaline rocks complexes...Contributions to Mineralogy and Petrology, Vol. 79, pp. 424-35.ColoradoAlkaline Rocks, Wet Mountains Area
DS1982-0570
1982
Hedge, C.E.Smith, C.B., Mccallum, M.E., Hedge, C.E.Rubidium-strontium Isotopic Ratios in Selected Lower Crust Upper Mantle nodules from Colorado-Wyoming Kimberlites.United States Geological Survey (USGS) OPEN FILE Report, No. 82-0178, 22P.Colorado, WyomingKimberlite, State Line, Rocky Mountains
DS201805-0963
2018
Hedge, V.S.McKenzie, N.R., Smyre, A.J., Hedge, V.S., Stockli, D.F.Continental growth histories revealed by detrital zircon trace elements: a case study from India. Geology, Vol. 46, 3, pp. 275-278.Indiacraton

Abstract: Simultaneous acquisition of detrital zircon Pb-Pb ages and trace element abundances from grains collected across the Indian craton, spanning ?3 b.y., reveals prominent shifts in Eu/Eu* and light and middle to heavy rare earth element ratios. These shifts correspond to a ca. 3.0-2.2 Ga interval of crustal thickening during Indian craton formation, followed by a period wherein arc magmatism occurred along thinner craton margins from ca. 1.9 to 1.0 Ga, with arc magmatism concentrated along attenuated continental margins after ca. 1.0 Ga. Similar temporal shifts in trace element concentrations are recognized in global whole-rock compilations. We propose that the post-1.0 Ga increase in juvenile magmatism reflects a switch to lateral arc terrane accretion as the primary style of continental growth over the past billion years.
DS2002-0694
2002
Hedlin, M.A.Hedlin, M.A., Shearer, P.M.Probing mid-mantle heterogeneity using PKP coda wavesPhysics of the Earth and Planetary Interiors, Vol. 130, No. 3-4, pp. 195-208.MantleGeophysics - seismics, Core-mantle boundary
DS1999-0659
1999
Hedlin, M.A.H.Shearer, P.M., Flanagan, M.P., Hedlin, M.A.H.Experiments of migration processing of SS precursor dat a to image Upper mantle discontinuity structure.Journal of Geophysical Research, Vol. 104, No. 4, Apr. 10, pp. 7229-42.MantleDiscontinuity
DS1970-0527
1972
Heeley, G.P.Heeley, G.P.Meeting New Demands for Mine "dust"Johannesburg: International Diamond Annual, Vol. 2, PP. 277-278.South AfricaDiamond Mining Recovery, Kimberlite Pipes
DS200512-0414
2005
Heemskerk, M.Heemskerk, M.Collecting dat a in artisanal and small scale mining communities: measuring progress towards more sustainable livelihoods.Natural Resources Forum, Vol.29, 1, pp. 82-87.Not specific to diamonds
DS201212-0290
2012
Heenan BlaikieHeenan BlaikieCSA provides guidance to clarify use and disclosure od preliminary economic assessments.Heenan Blaikie, Aug. 16, 3p. SummaryCanadaLegal - PEA
DS1998-1510
1998
Heeremans, M.Van Balen, R.T., Heeremans, M.Middle Proterozoic early Paleozoic evolution of central Baltoscandi nan intracratonic basins: evidence diapirs..Tectonophysics, Vol. 300, No. 1-4, Dec. 31, pp. 131-42.Norway, Sweden, ScandinaviaTectonic, Craton - Baltoscandia
DS2000-0461
2000
Heeremans, M.Kaikkonen, P., Moisio, K., Heeremans, M.Thermomechanical lithospheric structure of the Central Fennoscandian ShieldPhysical Earth and Planetary Interiors, Vol. 119, No.3-4, May. pp.209-35.Finland, Baltic Shield, FennoscandiaGeothermometry, Tectonics, seismicity
DS1930-0217
1936
Heertje, H.Heertje, H.Die Diamantbewerkers Van AmsterdamAmsterdam: D.b. Centens Uitgevers Maatschappy, 317P.GlobalAmsterdam Diamond Trade, Kimberley
DS1989-1338
1989
Hefferan, K.Saquaque, A., Admou, H., Karson, J., Hefferan, K., Reuber, I.Precambrian accretionary tectonics in the Bou-Azzer-El Graara region, Anti-Atlas, MoroccoGeology, Vol. 17, No. 12, December pp. 1107-1110MoroccoOphiolite, Late Proterozoic
DS2000-0401
2000
Hefferan, K.P.Hefferan, K.P., Admou, H., Saquaque, A.Anti-Atlas (Morocco) role in Neoproterozoic western GondwanaPrecambrian Research, Vol. 103, No. 1-2, Sept. pp.89-96.MoroccoTectonics, Gondwana
DS1992-0693
1992
Hefferman, V.Hefferman, V.Canada - exploration overview of diamond play in CanadaSeg Newsletter, No. 9, April p. 16Northwest TerritoriesNews item, Dia Met, BHP, Monopros
DS200412-0814
2004
Hefferman, V.Hefferman, V.Mineral property valuation. International movement to standardize property valuation gains momentum.Engineering and Mining Journal, August pp. 21-22,24,26.AustraliaEconomics - not specific to diamonds
DS200812-0460
2007
Hefferman, V.Hefferman, V.Renard pre-feasibility hinges on access, diamond value.Diamonds in Canada Magazine, Northern Miner, November pp. 26-27.Canada, QuebecNews item - Renard
DS200812-0461
2007
Hefferman, V.Hefferman, V.It's the homestretch for De Beers at Victor.Diamonds in Canada Magazine, Northern Miner, November pp. 23-25.Canada, Ontario, AttawapiskatNews item - Victor
DS201112-0426
2011
Hefferman, V.Hefferman, V.The Point Lake 'epiphany' how a single discovery spawned an entire industry.Diamonds in Canada Magazine, Northern Miner, November pp. 12-19.Canada, Northwest TerritoriesHistory of companies
DS201712-2692
2017
Hefferman, V.Hiyate, A., Hefferman, V.Dominion's latest transformation .. Next chapter Washington Companies takeover is just the latest twist in the company's history.Diamonds In Canada Magazine, Northern Miner, Nov. pp. 4-5.Canada, Northwest Territoriesdeposit - Ekati
DS202203-0351
2022
Heffernan, A.Heffernan, A.Development, conservation, empowerment: the trilemma of community-based natural resource management in Namibia.Environmental Management, Vol. 69, pp.480-491.pdfAfrica, NamibiaESG

Abstract: Community-Based Natural Resource Management (CBNRM) is a form of resource governance that has been widely popularized across southern Africa. CBNRM consists of three main goals or pillars which include economic development, environmental conservation, and community empowerment. It is intended to devolve control of certain natural resources from national government to local communities. The idea being that local residents will manage resources more sustainably and break neopatrimonial webs that have led to mismanagement and protracted underdevelopment. However, with communities there are important politics that often go understudied and there are instances where the same type of issues that going local was intended to circumvent, are re-engendered at the local level. Beyond this, CBNRM cannot only be understood as a form of domestic resource governance that happens in a vacuum and instead there are important politics and power imbalances between local, national, and global actors, that sees the will of some win out over others. As a result of these power asymmetries, I argue that the three goals of CBNRM form a trilemma in which the realization of one goal undermines success in achieving one or both of the others. As a result, CBNRM programs have failed to achieve the success proponents envision. Thus, it becomes integral to understand and account for the politics involved, rather than to analyze CBNRM as an apolitical policy fix for domestic conservation as much of the literature presents it as.
DS200512-0415
2005
Heffernan, V.Heffernan, V.Canada's diamond potential sparkles. The north remains the focus of exploration but Saskatchewan, Ontario and Quebec are also in the spotlight.Investment Research, August pp. 33-36.CanadaNews item - projects and overview
DS200712-0424
2007
Heffernan, V.Heffernan, V.Victor mine. Ontario's first diamond mine approaches production. Provinical avarice taints Victor mine on eve of opening.Diamonds in Canada Magazine, Northern Miner, June p. 10-13.Canada, Ontario, AttawapiskatVictor mine
DS200812-0462
2008
Heffernan, V.Heffernan, V.Is Amaruk the real deal? Buoyed by early results, Diamonds North seeks size in Nunavut's most promising diamond camp.Northern Miner, Diamonds in Canada, June pp. 2-5.Canada, NunavutHistory, overview
DS200812-0463
2008
Heffernan, V.Heffernan, V.Taher-ible.... little room for error reality and then things get rough.Northern Miner, Mining Markets, Vol. 1, 1, pp. 32-36.Canada, NunavutJericho mine
DS201112-0427
2010
Heffernan, V.Heffernan, V.A major gamble .. for metal miners dabbling in diamonds can mean a big payoff or dashed hopes. History of BHP, Rio, Teck, Newmont, Kinross.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 18-20.CanadaNews item - history
DS201312-0374
2013
Heffernan, V.Heffernan, V.Airborne EM methods: be wary of relying on the tried and true. Brief mention of EkatiEarthExplorer @geosoft.com, 1p. PrecisTechnologyGeophysics
DS201412-0350
2014
Heffernan, V.Heffernan, V.Rediscovering its swagger. A look at how Canada's minerals industry can adapt in the face of uncertainty. Core Magazine , Fall, pp. 4,5,6,8,9.CanadaDiscoveries - costs, mine-life trends, reglatories
DS201212-0060
2012
Hefffrich, G.R.Bastow, I.D., Kendall, J.M., Brisbourne, A.M., Snyder, D.B., Thompson, D., Hawthorne, D., Hefffrich, G.R., Wookey, J., Horleston, A., Eaton, D.The Hudson Bay lithospheric experiment.Astronomy and Geophysics, pp. 6.21-6.24.Canada, Ontario, QuebecGeophysics - seismics
DS2003-0572
2003
Heffrich, G.Heffrich, G., Ascencio, E., Knapp, J., Owens, T.Transition zone structure in a tectonically inactive area: 410 and 660 km discontinuityGeophysical Journal International, Vol. 155, 1, pp. 193-199.North Sea, EuropeGeophysics - seismics, mantle
DS200412-0815
2003
Heffrich, G.Heffrich, G., Ascencio, E., Knapp, J., Owens, T.Transition zone structure in a tectonically inactive area: 410 and 660 km discontinuity properties under the northern North Sea.Geophysical Journal International, Vol. 155, 1, pp. 193-199.EuropeGeophysics - seismics, mantle
DS1992-0694
1992
Heflin, J.R.Heflin, J.R., Garito, A.F.Buckministerfullerene: optics beyond the limitsNature, Vol. 356, No. 6366, March 19, p. 192GlobalFullerenes, Optics
DS2000-0402
2000
Hegardt, E.Hegardt, E., Cornell, D.H.A 1.0 Ga crustal subduction and exhumation model for BalticaJournal of African Earth Sciences, p. 38. abstract.Baltic States, Norway, Sweden, KolaSubduction, Tectonics
DS1989-0540
1989
Hegarty, K.A.Green, P.F., Duddy, I.R., Leslett, G.M., Hegarty, K.A., GleadowThermal annealing of fission tracks in apatite, 4. Quantitative modelling techniques and extension to geological timescalesChemical Geology, Vol. 79, No. 2, August 1, pp. 155-GlobalGeochronology, Timescales
DS200612-0629
2005
Hegarty, K.A.Jackson, M.P.A., Hudec, M.R., Hegarty, K.A.The great West African Tertiary coastal uplift: fact or fiction? A perspective from the Angola Rift.Tectonics, Vol. 24, 6, TC6013. 10.1029/2005 TC1836Africa, West Africa, AngolaGeomorphology
DS2000-0151
2000
Hegde, G.V.Chadwick, B., Vasudev, V.N., Hegde, G.V.The Dharwar Craton, southern India, interpreted as the result of Late Archean oblique convergence.Precambrian Research, Vol. 99, No. 1-2, pp. 91-111.India, south IndiaTectonics, Craton - Dharwar
DS200812-0464
2008
Hegde, V.S.Hegde, V.S., Chavadi, V.C.Geochemistry of dykes around Arabali, western Dharwar Craton and petrogenetic inferences.Journal of the Geological Society of India, Vol. 71, 5, pp. 651-660.IndiaDykes
DS202007-1135
2020
Hegde, V.S.Corfu, F., Hegde, V.S.U-Pb systematics of the western Dharwar craton - glimpse of a billion year history of crustal evolution and relations to ancient supercratons.Journal of South American Earth Sciences, Vol. 102, 102659, 12p. PdfIndiageochronology

Abstract: The Dharwar Craton developed progressively over a billion years, through two main stages of crustal growth separated by a few-hundred million year long period of relative quiescence. The first stage between 3.4 and 3.0 Ga developed a proto-craton, which was considerably amplified during the second main stage between 2.7 and 2.4 Ga, through extensive magmatism, tectonism, and crustal consolidation. This paper reports U-Pb dating results obtained in four specific areas of the craton, with the data encompassing key moments in this long development. Rocks formed during the proto-craton stage include a 3089 Ma augen gneiss and a 2973 Ma evolved granite, the latter of which marks the final cratonization event of the proto-craton. The beginning of the second main stage is recorded in this study by 2650 Ma tonalite and trondhjemite, a 2623 Ma granite dyke cutting augen gneiss, and 2614, 2602 and 2588 Ma volcanic rocks. Titanite responded differently to the long evolution, as a function of location and type of overprint. It preserved an original 2973 Ma magmatic age in the west, but was reset and/or crystallized during secondary events in central domains of the craton, yielding ages between 2590 and 2360 Ma. A diorite stock intruded at 2207 Ma in the consolidated crust. It is correlated with the Anantapur-Kunigal mafic dyke swarm, one of a series of such events in the Dharwar Craton between 2.35 and 1.79 Ma. In terms of its overall evolution the Dharwar Craton has an affinity with the Slave clan, which includes the Wyoming and Zimbabwe cratons. It also matches many features in the evolution of the São Francisco Craton, a probable other member of Sclavia. This is in contrast to the Amazonian Craton, which has more affinity with the Superior clan.
DS1997-0498
1997
Hegenberg, F.E.N.Hegenberg, F.E.N.Brazilian mining industry in the age of liberalisation privitising CVRDJournal of Mineral Policy, Vol. 12, No. 3, pp. 2-10BrazilEconomics, Privitization, legal
DS1985-0043
1985
Hegenberger, W.Balfour, D.J., Hegenberger, W., Medlycott, A.S., Wilson, K.J.Kimberlites Near Sikereti, North Eastern Southwest Africa/namibia.Communs. Geological Survey Swa/namibia., Vol. 1, PP. 69-77.Southwest Africa, NamibiaHistory, Pipe, Lithology, Petrography, Xenoliths, Age Of Emplacement
DS200812-0192
2008
Hegger, E.Chakhmouradian, A.H., Bohm, C.O., Demeny, A., Reguir, E.P., Hegger, E., Halden, N.M., Yang, P.Kimberlite from Wekusko Lake, Manitoba: a diamond indicator bearing beforsite and not a kimberlite, after all.9IKC.com, 3p. extended abstractCanada, manitobaCarbonatite
DS2000-0539
2000
HegnerKroner, A., Willner, A.P., Collins, A., Hegner, MuhongoThe Mozambique Belt of East Africa and Madagascar: a new zircon and neodymium ages - implications Rodinia, GondwanaJournal of African Earth Sciences, p. 49. abstract.GlobalSupercontinent - Gondwana
DS1989-0612
1989
Hegner, E.Hegner, E., Kyser, T.K., Hulbert, L.neodymium, Strontium and Oxygen isotopic constraints on the petrogenesis of mafic intrusions in the Proterozoic Trans-Hudson orogen of central CanadaCanadian Journal of Earth Sciences, Vol. 26, No. 5, May pp. 1027-1035OntarioGeochronology, Mafic intrusions
DS1989-0613
1989
Hegner, E.Hegner, E., Kyserm T.K., Hulbert, L.neodymium, Strontium, and Oxygen isotopic constraints on the petrogenesis of mafic intrusions in the Proterozoic Trans Hudson OrogenCanadian Journal of Earth Sciences, Vol. 26, pp. 1027-35.Saskatchewan, ManitobaGeochronology
DS1994-0752
1994
Hegner, E.Hegner, E., Kroner, A., Hunt, P.A precise uranium-lead (U-Pb) (U-Pb) zircon age for the Archean Pongola Supergroup volcanics inSwazilandJournal of African Earth Sciences, Vol. 18, No. 4, May pp. 339-342GlobalGeochronology, Archean
DS1995-0780
1995
Hegner, E.Hegner, E., Ruddick, J.C., Fortier, S.M., Hulbert, L.neodymium, Strontium, Phosphorus, Argon, and Oxygen isotopic systematics of Sturgeon Lake kimberlite-emplacement age, alteration, source..Contributions to Mineralogy and Petrology, Vol. 120, No. 2, Jun. pp. 212-222.SaskatchewanGeochronology, Deposit -Sturgeon Lake
DS1995-0781
1995
Hegner, E.Hegner, E., Walter, H.J., Satir, M.lead, Strontium, neodymium isotope compositions and trace element geochemistry of megacrysts and melilitites from UrachContributions to Mineralogy and Petrology, Vol. 122, pp. 322-335.GermanyTertiary Urach field, isotopes, European Volcanic Province
DS1997-0569
1997
Hegner, E.Kalt, A., Hegner, E., Satir, M.neodymium, Strontium, and lead isotopic evidence for diverse lithospheric mantle sources of East African carbonatiteTectonophysics, Vol. 278, No. 1-4, Sept. 15, pp. 31-46.Africa, east Africa, Tanzania, KenyaTectonics, Rifting, Carbonatite
DS1998-0093
1998
Hegner, E.Beard, A.D., Downes, H., Hegner, E., Sablukov, S.M.Mineralogy and geochemistry of Devonian ultramafic minor intrusions of southern Kola Peninsula.Contributions to Mineralogy and Petrology, Vol. 130, pp. 288-303.Russia, Arkangelsk, Kola PeninsulaKimberlites, mellilites, Petrogenesis
DS2000-0538
2000
Hegner, E.Kroner, A., Hegner, E., Pidgeon, R.T.Age and magmatic history of the Antananrivo Block, central Madagascar: derived from zircon geochronologyAmerican Journal of Science, Vol. 300, No. 4, Apr. pp. 251-88.MadagascarMagmatism, Geochronology - age determinations, isotopic
DS2002-0174
2002
Hegner, E.Blusztajn, J., Hegner, E.Osmium isotope systematics of melilitites from the Tertiary Central European Volcanic province in SW Germany.Chemical geology, Vol. 189, 1-2, pp. 91-103.GermanyMelilitites, Geochronology
DS2003-0863
2003
Hegner, E.Mahotkin, I.L., Downes, H., Hegner, E., Beard, A.D.Devonian dike swarms of alkaline, carbonatitic and primitiv magma type rocks from the8ikc, Www.venuewest.com/8ikc/program.htm, Session 4, POSTER abstractRussia, Kola PeninsulaMantle geochemistry
DS200412-0439
2004
Hegner, E.Demeny, A., Vennemann, T.W., Hegner, E., Nagy, G., Milton, J.A., Embey-Isztin, A., Homonnay, Z., Dobosi, G.Trace element and C O Sr Nd isotope evidence for subduction related carbonate silicate melts in mantle xenoliths ( Pannonian BasLithos, Vol. 75, 1-2, July pp. 89-113.Europe, HungarySubduction, trace element fingerprinting, petrogenetic
DS200812-0194
2008
Hegner, E.Chakhmouradian, A.R., Demeny, A., Reguir, E.P., Hegner, E., Halden, N.M., Yang, P.'Kimberlite' from Wekusko Lake, Manitoba: re-assessment and implications for further exploration. Beforsite ( primary dolomite carbonatite)... 'notion' could beManitoba Geological Survey, Nov. 21, 1p. abstract.Canada, ManitobaPetrology - potentially diamondiferous
DS200812-0296
2007
Hegner, E.Downes, H., Mahotkin, I.I., Beard, A.D., Hegner, E.Petrogenesis of alkali silicate, carbonatitic and kimberlitic magmas of the Kola alkaline carbonatite province.Vladykin Volume 2007, pp. 45-56.Russia, Kola PeninsulaCarbonatite
DS201012-0094
2009
Hegner, E.Chakhmouradian, A.R., Bohm, C.O., Demeny, A., Reguir, E.P., Hegner, E., Creaser, R.A., Halden, N.M., Yang, P.'Kimberlite' from Wekusko Lake Manitoba: actually a diamond indicator bearing dolomite carbonatite.Lithos, Vol. 112 S pp. 347-357.Canada, ManitobaCarbonatite
DS201212-0617
2012
Hegner, E.Sajeev, K., Windley, B.F., Hegner, E., Komiya, T.High temperature, high pressure granulites ( retrogressed eclogites) in the central region of the Lewisian NW Scotland: crustal scale subduction in the Neoarchean.Gondwana Research, in pressEurope, ScotlandEclogite
DS201811-2586
2018
Hegner, E.Kroner, A., Nagel, T.J., Hoffmann, J.E., Liu, X., Wong, J., Hegner, E., Xie, H., Kasper, U., Hofmann, A., Liu, D.High temperature metamorphism and crustal melting at ca. 3.2 Ga in the eastern Kaapvaal craton.Precambrian Research, Vol. 317, pp. 101-116.Africa, South Africacraton

Abstract: The question of whether high-grade metamorphism and crustal melting in the early Archaean were associated with modern-style plate tectonics is a major issue in unravelling early Earth crustal evolution, and the eastern Kaapvaal craton has featured prominently in this debate. We discuss a major ca. 3.2?Ga tectono-magmatic-metamorphic event in the Ancient Gneiss Complex (AGC) of Swaziland, a multiply deformed medium- to high-grade terrane in the eastern Kaapvaal craton consisting of 3.66-3.20?Ga granitoid gneisses and infolded greenstone remnants, metasedimentary assemblages and mafic dykes. We report on a 3.2?Ga granulite-facies assemblage in a metagabbro of the AGC of central Swaziland and relate this to a major thermo-magmatic event that not only affected the AGC but also the neighbouring Barberton granitoid-greenstone terrane. Some previous models have related the 3.2?Ga event in the eastern Kaapvaal craton to subduction processes, but we see no evidence for long, narrow belts and metamorphic facies changes reflecting lithospheric suture zones, and there is no unidirectional asymmetry in the thermal structure across the entire region from Swaziland to the southern Barberton granite-greenstone terrane as is typical of Phanerozoic and Proterozoic belts. Instead, we consider an underplating event at ca. 3.2?Ga, giving rise to melting in the lower crust and mixing with mantle-derived under- and intraplated mafic magma to generate the voluminous granitoid assemblages now observed in the AGC and the southern Barberton terrane. This is compatible with large-scale crustal reworking during a major thermo-magmatic event and the apparent lack of a mafic lower crust in the Kaapvaal craton as shown by seismic data.
DS202009-1630
2020
Hegner, E.Hegner, E., Rajesh, S., Willbold, M., Muller, D., Joachimiski, M., Hofmann, M., Linnemann, U., Zieger, J., Pradeepkumar, A.P.Sediment derived origin of the putatative Munnar carbonatite, South India.Journal of Asian Earth Science, Vol. 200, 104432, 18p. PdfIndiadeposit - Munnar

Abstract: Metacarbonate assemblages in high-grade metamorphic terranes often pose challenges when trying to distinguish between mantle-derived carbonatite and sedimentary carbonate protoliths. We present a study of granulite-facies metacarbonate samples of the putative Munnar carbonatite described as decimeter-thick dikes and veins, and layers of a meter-thick metacarbonate and calc-silicate assemblage, respectively. Thin sections of the metacarbonate dike samples show absence of pyrochlore and ubiquitous scapolite, titanite, wollastonite, and detrital zircons are compatible with impure limestone protoliths. Nd and Sr isotope compositions indicate protoliths with Paleoproterozoic crustal residence times which contrast the mantle sources of Indian and global carbonatites. Trace-element patterns display the characteristics of upper crust, and Ce- and Y-anomalies in a number of samples suggest protolith formation under marine conditions. Carbon and oxygen isotope compositions of the metacarbonate samples interlayered with calc-silicate rocks are similar to those in marine limestone. The metacarbonate dikes, however, show mantle-like compositions which are interpreted as reflecting equilibration with mantle-derived CO2 during granulite-facies metamorphism. The dikes yielded a U-Pb zircon crystallization age of 1020 ± 70 Ma and a cross-cutting quartz syenite, thought to be cogenetic, a magmatic age of 620 ± 35 Ma; the hosting gneiss provided a magmatic age of 2452 ± 14 Ma. We conclude that the layered metacarbonate and calc-silicate rocks represent a former marine limestone and marl sequence and the metacarbonate dikes and veins small-volume melts of crust-derived carbonate-rich sediment.
DS1992-0210
1992
Hei, K.J.Canil, D., Hei, K.J.Constraints on the origin of mantle-derived low Calcium garnetsContributions to Mineralogy and Petrology, Vol. 109, No. 4, February pp. 421-430MantleGarnets -low calcium.
DS201504-0204
2015
Heidari, H.Kaminsky, F.V., Ryabchikov, I.D., McCammon, C.A., Longo, M., Abakumov, A.M., Turner, S., Heidari, H.Oxidation potential in the Earth's lower mantle as recorded by ferropericlase inclusions in diamond.Earth and Planetary Science Letters, Vol. 417, pp. 49-56.South America, BrazilDeposit - Juina
DS1970-0558
1972
Heidari, M.Mcginnis, L.D., Heigold, P.C., Heidari, M., Carlson, D.R.Second Generation Gravity Studies in the MidcontinentGeological Society of America (GSA), Vol. 4, No. 5, P. 337. (abstract.).GlobalMid-continent
DS2003-0597
2003
Heidelbach, F.Holtzman, B.K., Kohlstedt, D.L., Zimmerman, M.E., Heidelbach, F., Hiraga, T.Melt segregation and strain partitioning: implications for seismic anisotropy and mantleScience, No. 5637, August 29,p. 1227-29.MantleGeophysics - seismic
DS200412-0845
2003
Heidelbach, F.Holtzman, B.K., Kohlstedt, D.L., Zimmerman, M.E., Heidelbach, F., Hiraga, T., Hustoft, J.Melt segregation and strain partitioning: implications for seismic anisotropy and mantle flow.Science, No. 5637, August 29,p. 1227-29.MantleGeophysics - seismic
DS200612-1420
2005
Heidelbach, F.Terry, M.P., Heidelbach, F.Deformation enhanced metamorphic reactions and the rheology of high pressure shear zones, Western Gneiss region, Norway.Journal of Metamorphic Geology, Vol. 24, 1, pp. 3-18.Europe, NorwayUHP
DS1950-0216
1955
Heidgen, H.Heidgen, H.The Diamond Seeker in Tanganyika. the Story of John Williamson.Austria: Verlag Styria., 139P.Tanzania, East AfricaKimberlite
DS1995-0782
1995
Heidi, F.Heidi, F., Wlotzha, F.MeteoritesSpringer, 242p. approx. $ 30.00GlobalBook -ad, Meteorites
DS1950-0475
1959
Heidigen, H.Heidigen, H.The Diamond Seeker. (biography of Williamson)London: Blackie., Tanzania, East AfricaKimberlite, Kimberley, Janlib, Biography
DS1960-0152
1961
Heier, K.S.Heier, K.S.Layered Gabbro, Hornblendite, Carbonatite and Nepheline Syenite on Stjernoy.Norsk Geol. Tidsskr., Vol. 41, PP. 109-155.Norway, ScandinaviaPetrography
DS1960-0249
1962
Heier, K.S.Heier, K.S.A Note on the Uranium, Thorium, and Potassium Contents in the Nepheline syenite and Carbonatite on Stjernoy.Norske Geol. Tidsskr., Vol. 42, PP. 287-292.Norway, ScandinaviaUltramafic And Related Rocks, Uranium, Thorium
DS1960-0460
1964
Heier, K.S.Heier, K.S.Geochemistry of the Nepheline Syenite on StjernoyNorske Geol. Tidsskr., Vol. 44, PP. 205-215.Norway, ScandinaviaUltramafic And Related Rocks
DS1970-0155
1970
Heier, K.S.Mysen, B.O. , Heier, K.S.A Note on the Field Occurrence of a Large Eclogite on Hareid,sunmore, Western Norway.Norske Geol. Tidsskr., Vol. 50, No. 1, PP. 93-96.Norway, ScandinaviaBlank
DS1970-0572
1972
Heier, K.S.Mysen, B.O., Heier, K.S.Petrogenesis of Eclogites in High Grade Metamorphic Terrains As Exemplified by the Hereidland Eclogite, Western Norway.Contributions to Mineralogy and Petrology, Vol. 36, PP. 73-94.Norway, ScandinaviaPetrography
DS1992-0695
1992
Heier, K.S.Heier, K.S.Lands cape geochemistry: retrospect and prospect -1990. critical comments #1Applied Geochemistry, Vol. 7, No. 1, January pp. 57-59GlobalGeomorphology, geochemistry, Environmental geochemistry -review
DS1997-0202
1997
Heiffrich, G.R.Collier, J.D., Heiffrich, G.R.Topography of the 410 and 660 km seismic discontinuties in the Izu - Bonin subduction zone.Geophys. Research Letters, Vol. 24, No. 12, June 15, pp. 1535-38.GlobalSubduction zone, Geophysics - seismics
DS1970-0558
1972
Heigold, P.C.Mcginnis, L.D., Heigold, P.C., Heidari, M., Carlson, D.R.Second Generation Gravity Studies in the MidcontinentGeological Society of America (GSA), Vol. 4, No. 5, P. 337. (abstract.).GlobalMid-continent
DS1991-0698
1991
Heigold, P.C.Heigold, P.C.Seismic reflection and seismic refraction surveying in northeasternIllinoisIllinois State Geological Survey, Environmental Geology Report No. 36, 52p. (Ontario Geological Survey (OGS))GlobalGeophysics -seismics, Refraction
DS1991-0910
1991
Heigold, P.C.Kolata, D.R., Heigold, P.C.Proterozoic crustal domain boundary in the southern part of the IllinoisBasinGeological Society of America, Abstract Volume, Vol. 23, No. 3, March p. 22GlobalGeophysics, Cocorp
DS1993-0647
1993
Heigold, P.C.Heigold, P.C., Kolata, D.R.Proterozoic crustal boundary in the southern part of the Illinois BasinTectonophysics, Vol. 217, pp. 307-319GlobalCocorp, Geophysics -seismics
DS1995-1513
1995
Heigold, P.C.Potter, C.J., Goldhaber, M.B., Heigold, P.C., Drahovzal, J.Structure of the Reelfoot Rough Creek Rift System, Fluorspar area fault complex and Hicks Dome...United States Geological Survey (USGS) Prof. paper, No. 1538- Q, 20p.Midcontinent, Illinois, KentuckyGeophysics - seismics
DS2002-1651
2002
Heijboer, T.C.Van Roermund, H.L.M., Carswell, D.A., Drury, M.R., Heijboer, T.C.Microdiamonds in a megacrystic garnet websterite pod from Bardane on the island ofGeology, Vol. 30, 11, Nov. pp. 959-62.NorwaySubduction - deep continental, diamond genesis
DS1994-0460
1994
Heikamp, S.Duba, A., Heikamp, S., Meurer, W., NOver, G., Will, G.Evidence from borehole samples for the role of accessory minerals in lower crustal conductivity.Nature, Vol. 367, No. 6458, January 6, pp. 59-61.MantleSubduction
DS2000-0702
2000
Heikkinen, P.Neprochov, Y.P., Semenov, G.A., Heikkinen, P.Comparison of the crustal structure of the Barents Sea and the Baltic Shield from seismic data.Tectonophysics, Vol.321, No.4, June 30, pp.429-48.Baltic States, Norway, Sweden, Kola, RussiaTectonics, Geophysics - seismics
DS2001-0626
2001
Heikkinen, P.Korje, A., Heikkinen, P., Aaro, S.Crustal structure of the northern Baltic Sea paleoriftTectonophysics, Vol. 331, No. 4, Feb. 28, pp. 341-58.Baltic SeaTectonics - rifting
DS200612-0755
2006
Heikkinen, P.Kuusisto, M., Kukkonen, L.T., Heikkinen, P., Pesonen, L.J.Lithological interpretation of crustal composition in the Fennoscandian Shield with seismic velocity data.Tectonophysics, in pressEurope, Finland, FennoscandiaGeophysics - seismics, wide-angle reflection
DS1995-1003
1995
Heikkinen, P.J.Korja, A., Heikkinen, P.J.Proterozoic extensional tectonics of the central Fennoscandian Shield:results from Baltic and BothnianTectonics, Vol. 14, No. 2, April pp. 504-517.Fennoscandia, Finland, SwedenTectonics, BABEL, Geophysics -seismics, lithosphere
DS200812-0592
2008
Heikkinen, P.J.Korja, A., Heikkinen, P.J.Seismic images of Paleoproterozoic microplate boundaries in the Fennoscandian Shield.Geological Society of America Special Paper, 440, pp. 229-248.Europe, Finland, FennoscandiaGeophysics - seismic
DS1960-0850
1967
Heilammer, R.Kaplan, G., Faure, D., Ellroy, R., Heilammer, R.Contribution a L'etude de L'origine des LamproitesCentr. Rech. ( Pau-snpa ) Bulletin., Vol. 1, No. 1, PP. 153-159.Australia, Western AustraliaLeucite, Lamproite, Mt. North, Geochronology, K Ar, Rb Sr
DS1920-0448
1929
Heiland, C.A.Heiland, C.A.Geophysical Methods of Prospecting: Principles and Recent Successes.Col. Sch. Mines Quarterly, Vol. 24, MARCH, PP. 1-163. (P. 45.).United States, Gulf Coast, Arkansas, PennsylvaniaGeophysics, Prospecting Methods, Kimberlite
DS1930-0162
1934
Heiland, C.A.Heiland, C.A.Precious Stones (1934)American Institute Mining Engineering Transactions, Vol. 110, P. 571.United States, Gulf Coast, ArkansasDiamond Occurrence
DS2000-0403
2000
Heilbron, M.Heilbron, M., Brito Neves, B.B., Pimentel, M.M., et al.Neoproterozoic orogenic systems in eastern, central and northeastern Brasil,and evolution of Gondwana.Igc 30th. Brasil, Aug. abstract only 1p.Brazil, West AfricaTectonics - Craton, orogeny
DS201312-0375
2013
Heilbronner, R.Heilbronner, R., Barrett, S.Image analysis in Earth Sciences…. Micro structures and textures.Springer, $ 99. 00 520p.TechnologyBook - textures
DS201905-1061
2019
Heilimo, E.Nandy, J., Dey, S., Heilimo, E.Neoarchean magmatism through arc and lithosphere melting: evidence from eastern Dharwar craton.Geological Journal, doi.10.1002/gj.3498Indiacraton

Abstract: The Neoarchaean era is characterized by rapid crustal growth corresponding to some fundamental global changes in geodynamic processes. However, the nature of crustal growth including the mechanism and tectonic setting of the Neoarchaean are controversial issues. The eastern Dharwar Craton (EDC) exposes widespread Neoarchaean granite?greenstone belts, which provide an opportunity to evaluate the various models proposed for Neoarchaean crustal growth. In this study, we present field, petrographic, and geochemical data and discuss the petrogenesis and significance for crustal evolution for a suite of previously undescribed banded gneisses, TTG (tonalite-trondhjemite-granodiorite), biotite granites, alkali feldspar granite and gabbro. These rocks are associated with Neoarchaean metavolcanic and metapelites rocks of the Tsundupalle greenstone belt, in the eastern fringe of the EDC. Whole?rock major and trace element geochemical data are consistent with diverse sources, including both crust and enriched mantle in an evolving subduction zone. A convergent orogenic setting is proposed for interpreting the association of various granitoids in the Tsundupalle area. Finally, intrusion of crustally derived, highly silicic, alkali?rich granite, and mantle?derived gabbro emplaced in a post?subduction regime is proposed. Lithospheric delamination and attendant mantle melting are suggested as possible mechanisms for generation of these rocks. The understanding of generation of the different granitoid types along with gabbro provides significant insights into the mechanism of Neoarchaean crustal growth.
DS1995-0087
1995
Heimann, A.Baer, G., Heimann, A.Physics and chemistry of dykesBalkema, 350pGlobalDykes, geochemistry, Table of contents
DS200612-0558
2005
Heimbach, J.Heimbach, J.Ekati Diamond Mine - Panda, Koala and Fox, are these animals related? A comparison of ore body geology at the Ekati Diamond Mine.32ndYellowknife Geoscience Forum, p. 29 abstractCanada, Northwest TerritoriesGeology
DS200812-0248
2007
Heimbach, J.Coutts, B., Heimbach, J., Dyck, D.Panda, from pyrope to production ( now you've found a kimberlite, the work is just starting). BHP Billiton35th. Yellowknife Geoscience Forum, Abstracts only p. 11-12.Canada, Northwest TerritoriesMine planning - Panda
DS1988-0224
1988
Heimlich, R.A.Freeman, M.J., Palmer, D.F, Heimlich, R.A.Magnetic survey of the western serpentinite belt,northern HartfordCounty, MarylandSoutheastern Geology, Vol. 29, No. 2, December pp. 103-128GlobalUltramafic, laterite, Geophysics
DS1989-0614
1989
Hein, F.J.Hein, F.J.Evaluation of petrographic and mineralogic analysis of marine placersedimentsGeological Survey of Canada Open File, No. 2141, 73p. $ 43.00 Precision Microfilming, HalifaxGlobalAlluvial placers -general, Petrography
DS1999-0263
1999
Hein, F.J.Greggs, D.H., Hein, F.J.Lineaments and basement tectonics in the Western Canada sedimentary basin8th. Calgary Mining forum, 1p. abstractSaskatchewan, AlbertaCraton, Tectonics - lineaments
DS1995-0783
1995
Hein, J.Hein, J.The regulator's view of the valuation of mineral assets in expert reportsAustralian Institute of Mining and Metallurgy (AusIMM) Bulletin, No. 1, Feb, pp. 24-29AustraliaEconomics, Ore reserve valuation
DS201510-1784
2015
Hein, K.A.A.Markwitz, V., Hein, K.A.A., Miller, J.Compilation of West African mineral deposits: spatial distribution and mineral endowment. ( mentions diamonds)Precambrian Research, in press available, 21p.Africa, Mali, Mauritania, Senegal, Burkina Faso, Ghana, Ivory CoastMetallogeny

Abstract: The West African Craton is highly endowed in minerals, and their spatial and temporal distribution varies from single to multi-phase mineralization events. They are broadly related to three major tectono-metallogenic elements and formed during distinct mineral epochs: (1) In both Archean Shields (Kénéma-Man and Reguibat) and Paleoproterozoic domains (Baoulé-Mossi, Eglab). These are characterized by giant iron ore deposits that formed between ca. 2.5-2.3 Ga, nearly all gold, porphyry copper, lead-zinc and sedimentary manganese ore that developed between 2.2 and 2.1 Ga, and primary diamonds that formed between two intervals at ca. 2.2-2.0 Ga and in the Mesozoic. (2) Across Pan-African and Variscan belts. These are distinguished by major Precambrian IOCG's, copper-gold that formed at ca. 2.1 Ga and approximately 680 Ma, and Neoproterozoic sedimentary iron ore and phosphate deposits. (3) Within intracratonic and coastal basins. These include the development of Cenozoic lateritic bauxites over Mesozoic dolerites, Tertiary/Quaternary mineral sands deposits, oolitic iron ore and sedimentary phosphate deposits. Geological, spatial and temporal correlations using the multi-commodity West African Mineral Deposit Database highlight that gold and non-gold commodities formed in multiple phases. This commenced in the Liberian Orogeny (2.9-2.8 Ga) with the enrichment of iron ore, nickel sulphides, diamonds and gold in the earth's crust. The pre-Eburnean or Tangaean-EoEburnean-Eburnean I Event yielded gold, and the major Eburnean Orogeny yielded gold, iron ore, manganese, diamonds, magmatic nickel sulphides, copper-gold, lead-zinc, and REE minerals. Throughout the Pan-African event sedimentary manganese deposits, lead-zinc, REE minerals, sedimentary phosphates, and again gold were formed. Primary diamonds and magmatic nickel sulphides are related to the break-up of Gondwana, followed by an intense lateritic weathering period that formed bauxite deposits along the craton margin.
DS201512-1940
2015
Hein, K.A.A.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West African Craton. ( mentions kimberlites)Ore Geology Reviews, Oct 28 10.024Africa, West AfricaReguibat shield, Kenema-Man shield

Abstract: The West African Craton hosts major resources of gold, iron ore, aluminium ore, diamonds, phosphates and manganese. This portfolio of ore deposits is linked to the formation of Archean -Paleoproterozoic greenstone belts, Jurassic rifting and extended periods of Mesozoic to Cenozoic weathering and erosion. We give a brief overview of the temporal and spatial distribution patterns of West African ore deposits with emphasis on the main commodity types. The oldest ore forming processes generated major resources in iron ore and gold in the Kénéma -Man and Reguibat Shields during the Neo-Archean. The majority of gold, porphyry copper, lead -zinc and sedimentary manganese deposits formed during the Paleoproterozoic, dominantly within the Baoulé-Mossi domain. At the same time diamond-bearing kimberlites developed in Ghana. Another distinct diamond event has been recognized in the Mesozoic of the Kénéma -Man shield. Isolated occurrences of IOCG's as well as copper -gold and gold formed in Pan-African/Variscan belts. During the Neoproterozoic, the majority of mineralization consists of sedimentary iron ore and phosphate deposits located within intracratonic basins. During the Phanerozoic aluminium ore, phosphates and mineral sands concentrated along the margins of the coastal and intracratonic basins.
DS201604-0618
2016
Hein, K.A.A.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West African craton. Mentions diamonds in S.L.Ore Geology Reviews, in press available 6p.Africa, Sierra LeoneMetallogeny
DS201605-0845
2016
Hein, K.A.A.Hein, K.A.A.West African mineral atlas monograph.Ore Geology Reviews, in press available outline 5p.Africa, West AfricaBook - Atlas
DS201608-1422
2016
Hein, K.A.A.Markwitz, V., Hein, K.A.A., Jessell, M.W., Miller, J.Metallogenic portfolio of the West Africa craton. Mentions diamonds in Ghana, Mali and GuineaOre Geology Reviews, Vol. 78, pp. 558-563.Africa, Ghana, Mali, GuineaAlluvials
DS1989-0615
1989
Hein, U.F.Hein, U.F.The genesis of the Gakara bastnaesite monazitedeposits: evidence from fluid inclusions79th. Annual Meeting Of The Geologische Vereinigung, Mineral, p. 34. (abstract.)GlobalBastnaesite, Alkaline
DS201312-0116
2013
Heine, C.Butterworth, N.P., Talsman, A.S., Muller, R.D., Seton, M., Bunge, H-P., Schuberth, B.S.A., Shephard, G.E., Heine, C.Geological, tomographic, kinematic and geodynamic constraints on the dynamics of sinking slabs.Earth Science Reviews, Vol. 126, pp. 235-249.MantleSubduction
DS201412-0087
2014
Heine, C.Butterworth, N.P., Talsma, A.S., Muller, R.D., Seton, M., Bunge, H-P., Schuberth, B.S.A., Shephard, G.E., Heine, C.Geological, tomographic, kinematic and geodynamic constraints on the dynamics of sinking slabs.Journal of Geodynamics, Vol. 73, pp. 1-13.MantleSubduction
DS201412-0351
2014
Heine, C.Heine, C., Brune, S.Oblique rifting of the Equatorial Atlantic: why there is no Saharan Atlantic Ocean.Geology, Vol. 42, 3, pp. 211-214.AfricaRift zone
DS201906-1327
2019
Heine, C.Muller, R.D., Zahirovic, S., Williams, S.E., Cannon, J., Seton, M., Bower, D.J., Tetley, M., Heine, C., Le Breton, E., Liu, S., Russell, S.H.J., Yang, T., Leonard, J., Gurnis, M.A global plate model including lithospheric deformation along major rifts and orogens since the Triassic.Tectonics, May 5, 36p. Mantleplate tectonics

Abstract: Global deep?time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic?Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hotspot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 million km2 in the Late Jurassic (~160?155 Ma), driven by a vast network of rift systems. After a mid?Cretaceous drop in deformation it reaches a high of 48 million km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate?mantle system.
DS201907-1562
2019
Heine, C.Muller, D., Zahirovic, S., Williams, S.E., Cannon, J., Seton, M., Bower, D.J., Tetley, M., Heine, C., Le Breton, E., Liu, S., Russell, S.H.J., Yang, T., Leonard, J., Gurnis, M.A global plate model including lithospheric deformation along major rifts and orogens since the Triassic.Tectonics, in press available, 37p.Africa, globalplate tectonics, rotation

Abstract: Global deep?time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic-Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 × 106 km2 in the Late Jurassic (~160-155 Ma), driven by a vast network of rift systems. After a mid?Cretaceous drop in deformation, it reaches a high of 48 x 106 km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate?mantle system.
DS201809-2109
2018
Heinen, B.Walter, M.J., Drewitt, J.W.E., Thomson, A.R., Zhang, H., Lord, O.T., Heinen, B.The fate of carbonate in oceanic crust subducted into Earth's mantle.Goldschmidt Conference, 1p. AbstractMantlesubduction

Abstract: The H/C ratio in earth’s exosphere is higher than it is in the source region of primitive basalts, suggesting an enriched carbon reservoir in the mantle[1]. A plausible explanation is that subduction of carbon may have enriched the mantle in recycled carbon over time. Average basaltic crust contains ~ 2 wt.% CO2 [2], and modeling of slab devolatilisation suggests that subducted carbonate may survive to be transported deeper into the mantle [3]. Carbonated oceanic crust should melt in the transition zone along most subduction geotherms due to a deep trough in the carbonated basalt solidus, and mineral inclusions in superdeep diamonds testify to carbonate melt in their formation [4]. Along cool subduction geotherms carbonate may subduct into the lower mantle, potentially enriching the deep mantle in carbon. Here we report on laser-heated diamond anvil cell experiments in the CaO-MgO-SiO2-CO2 and FeO-MgO-SiO2-CO2 systems at lower mantle pressures where we investigate the stability of carbonate in oceanic crust, and test for decarbonation and diamond forming reactions involving carbonate and coexisiting free silica. We find that carbonate reacts with silica to form bridgmanite ± Ca-perovskite + CO2 at pressures in the range of ~50 to 70 GPa. These decarbonation reactions form an impenetrable barrier to subduction of carbonate into the deeper lower mantle, however, slabs may carry solid CO2 (Phase V) into the deeper lower mantle. We also identify reactions where carbonate or CO2 dissociate to form diamond plus oxygen. We suggest that the deep lower mantle may become enriched in carbon in the form of diamond over time due to subduction of carbonate and solid CO2 and its eventual dissociation to form diamond plus oxygen. Release of oxygen during diamond formation may also provide a mechanism for locally oxidizing the deep mantle.
DS201903-0503
2019
Heinen, B.J.Drewitt, J.W.E., Walter, M.J., Zhang, H., McMahon, S.C., Edwards, D., Heinen, B.J., Lord, O.T., Anzellini, S., Kleppe, A.K.The fate of carbonate in oceanic crust subducted into Earth's lower mantle.Earth and Planetary Science Letters, Vol. 511, pp. 213-222.MantleBridgemanite

Abstract: We report on laser-heated diamond anvil cell (LHDAC) experiments in the FeO-MgO-SiO2-CO2 (FMSC) and CaO-MgO-SiO2-CO2 (CMSC) systems at lower mantle pressures designed to test for decarbonation and diamond forming reactions. Sub-solidus phase relations based on synthesis experiments are reported in the pressure range of ?35 to 90 GPa at temperatures of ?1600 to 2200 K. Ternary bulk compositions comprised of mixtures of carbonate and silica are constructed such that decarbonation reactions produce non-ternary phases (e.g. bridgmanite, Ca-perovskite, diamond, CO2-V), and synchrotron X-ray diffraction and micro-Raman spectroscopy are used to identify the appearance of reaction products. We find that carbonate phases in these two systems react with silica to form bridgmanite ±Ca-perovskite + CO2 at pressures in the range of ?40 to 70 GPa and 1600 to 1900 K in decarbonation reactions with negative Clapeyron slopes. Our results show that decarbonation reactions form an impenetrable barrier to subduction of carbonate in oceanic crust to depths in the mantle greater than ?1500 km. We also identify carbonate and CO2-V dissociation reactions that form diamond plus oxygen. On the basis of the observed decarbonation reactions we predict that the ultimate fate of carbonate in oceanic crust subducted into the deep lower mantle is in the form of refractory diamond in the deepest lower mantle along a slab geotherm and throughout the lower mantle along a mantle geotherm. Diamond produced in oceanic crust by subsolidus decarbonation is refractory and immobile and can be stored at the base of the mantle over long timescales, potentially returning to the surface in OIB magmas associated with deep mantle plumes.
DS1992-0633
1992
Heiner, T.Guocheng Pan, Moss, K., Heiner, T., Carr, J.R.A fortran program for three-dimensional cokriging with case demonstrationComputers and Geosciences, Vol. 18, No. 5, pp. 557-578GlobalGeostatistics, Program -cokriging
DS202009-1671
2020
Heinonen, A.Tiira, T., Janik, T., Skrzynik, T., Komminaho, K., Heinonen, A., Veikkolainen, T., Vakeva, S., Korja, A.Full scale crustal interpretation of Kokkola-Kymi ( KOKKY) seismic profile, Fennoscandian shield.Pure and Applied Geophysics, Vol. 177, 8, pp. 3775-3795. pdfEurope, Finlandgeophysics - seismics

Abstract: The Kokkola-Kymi Deep Seismic Sounding profile crosses the Fennoscandian Shield in northwest-southeast (NW-SE) direction from Bothnian belt to Wiborg rapakivi batholith through Central Finland granitoid complex (CFGC). The 490-km refraction seismic line is perpendicular to the orogenic strike in Central Finland and entirely based on data from quarry blasts and road construction sites in years 2012 and 2013. The campaign resulted in 63 usable seismic record sections. The average perpendicular distance between these and the profile was 14 km. Tomographic velocity models were computed with JIVE3D program. The velocity fields of the tomographic models were used as starting points in the ray tracing modelling. Based on collected seismic sections a layer-cake model was prepared with the ray tracing package SEIS83. Along the profile, upper crust has an average thickness of 22 km average, and P-wave velocities (Vp) of 5.9-6.2 km/s near the surface, increasing downward to 6.25-6.40 km/s. The thickness of middle crust is 14 km below CFGC, 20 km in SE and 25 km in NW, but Vp ranges from 6.6 to 6.9 km/s in all parts. Lower crust has Vp values of 7.35-7.4 km/s and lithospheric mantle 8.2-8.25 km/s. Moho depth is 54 km in NW part, 63 km in the middle and 43 km in SW, yet a 55-km long section in the middle does not reveal an obvious Moho reflection. S-wave velocities vary from 3.4 km/s near the surface to 4.85 km/s in upper mantle, consistently with P-wave velocity variations. Results confirm the previously assumed high-velocity lower crust and depression of Moho in central Finland.
DS201610-1875
2016
Heinonen, J.S.Jennings, E.S., Gibson, S.A., Maclennan, J., Heinonen, J.S.Deep mixing of mantle melts beneath continental flood basalt provinces: constraints from olivine hosted melt inclusions in primitive magmas. Etendeka and KarooGeochimica et Cosmochimica Acta, in press availableAfrica, NamibiaPicrite, ferroPicrite

Abstract: We present major and trace element compositions of 154 re-homogenised olivine-hosted melt inclusions found in primitive rocks (picrites and ferropicrites) from the Mesozoic Paraná-Etendeka and Karoo Continental Flood Basalt (CFB) provinces. The major element compositions of the melt inclusions, especially their Fe/Mg ratios, are variable and erratic, and attributed to the re-homogenisation process during sample preparation. In contrast, the trace element compositions of both the picrite and ferropicrite olivine-hosted melt inclusions are remarkably uniform and closely reflect those of the host whole-rocks, except in a small subset affected by hydrothermal alteration. The Paraná-Etendeka picrites and ferropicrites are petrogenetically related to the more evolved and voluminous flood basalts, and so we propose that compositional homogeneity at the melt inclusion scale implies that the CFB parental mantle melts were well mixed prior to extensive crystallisation. The incompatible trace element homogeneity of olivine-hosted melt inclusions in Paraná-Etendeka and Karoo near primitive magmatic rocks has also been identified in other CFB provinces and contrasts with findings from studies of basalts from mid-ocean ridges (e.g. Iceland and FAMOUS on the Mid Atlantic Ridge), where heterogeneity of incompatible trace elements in olivine-hosted melt inclusions is much more pronounced. We suggest that the low variability in incompatible trace element contents of olivine-hosted melt inclusions in near-primitive CFB rocks, and also ocean island basalts associated with moderately thick lithosphere (e.g. Hawaii, Galápagos, Samoa) may reflect mixing along their longer transport pathways during ascent and/or a temperature contrast between the liquidus and the liquid when it arrives in the crust. These thermal paths promote mixing of mantle melts prior to their entrapment by growing olivine crystals in crustal magma chambers. Olivine-hosted melt inclusions of ferropicrites from the Paraná-Etendeka and Karoo CFB have the least variable compositions of all global melt inclusion suites, which may be a function of their unusually deep origin and low viscosity.
DS201611-2115
2016
Heinonen, J.S.Jennings, E.S., Gibson, S.A., Maclennan, J., Heinonen, J.S.Deep mantle melts beneath continental flood basalt provinces: constraints from olivine hosted melt inclusions in primitive magmas.Geochimica et Cosmochimica Acta, Vol. 196, pp. 36-57.Africa, Namibia, AngolaParan-Etendeka, Karoo

Abstract: We present major and trace element compositions of 154 re-homogenised olivine-hosted melt inclusions found in primitive rocks (picrites and ferropicrites) from the Mesozoic Parana ´-Etendeka and Karoo Continental Flood Basalt (CFB) provinces. The major element compositions of the melt inclusions, especially their Fe/Mg ratios, are variable and erratic, and attributed to the re-homogenisation process during sample preparation. In contrast, the trace element compositions of both the picrite and ferropicrite olivine-hosted melt inclusions are remarkably uniform and closely re?ect those of the host whole-rocks, except in a small subset a?ected by hydrothermal alteration. The Parana ´-Etendeka picrites and ferropicrites are petrogenet- ically related to the more evolved and voluminous ?ood basalts, and so we propose that compositional homogeneity at the melt inclusion scale implies that the CFB parental mantle melts were well mixed prior to extensive crystallisation. The incompatible trace element homogeneity of olivine-hosted melt inclusions in Parana ´-Etendeka and Karoo primitive magmatic rocks has also been identi?ed in other CFB provinces and contrasts with ?ndings from studies of basalts from mid- ocean ridges (e.g. Iceland and FAMOUS on the Mid Atlantic Ridge), where heterogeneity of incompatible trace elements in olivine-hosted melt inclusions is more pronounced. We suggest that the low variability in incompatible trace element contents of olivine-hosted melt inclusions in near-primitive CFB rocks, and also ocean island basalts associated with moderately thick lithosphere (e.g. Hawaii, Gala ´pagos, Samoa), may re?ect mixing along their longer transport pathways during ascent and/or a temperature contrast between the liquidus and the liquid when it arrives in the crust. These thermal paths promote mixing of mantle melts prior to their entrapment by growing olivine crystals in crustal magma chambers. Olivine-hosted melt inclusions of ferropicrites from the Parana ´-Etendeka and Karoo CFB have the least variable compositions of all global melt inclusion suites, which may be a function of their unusually deep origin and low viscosity.
DS201909-2099
2019
Heinonen, J.S.Turunen, S.T., Luttinen, A.V., Heinonen, J.S., Jamal, D.L.Luenha picrites, central Mozambique - messengers from a mantle plume source of Karoo continental flood basalts?Lithos, Vol. 346-347, 16p. PdfAfrica, Mozambiquepicrites

Abstract: We present geochemical and isotopic (Nd, Sr) data for a picrite lava suite from the Luenha River and adjacent areas in Mozambique. The Luenha picrites represent a previously unknown type of picrites related to the Karoo large igneous province (LIP) and are distinguished by their notably low TiO2 contents (0.3-1.0?wt%) and coupling of high Nb/Y with low Zr/Y and Sm/Yb. Relatively high CaO and low Zn/Fe point to a peridotitic mantle source. Contamination-sensitive incompatible element ratios show that one lava flow is likely to be uncontaminated by the crust and its composition suggests a mantle source with primitive mantle-like incompatible element ratios and mildly depleted isotopic ratios (initial 87Sr/86Sr?=?0.7041 and ?Nd?=?+1.4 at 180?Ma). The primary melts of the Luenha picrites had MgO contents in the range of 13-21?wt%. Our preferred estimate for a primary melt composition (MgO?=?18?wt%) resembles experimental melts of fertile mantle peridotite at 3-4?GPa and indicates liquidus temperature of 1445-1582?°C. Geochemical similarities suggest the Luenha picrites were generated from the same overall primitive mantle-like reservoir that produced the main volume of Karoo flood basalts in the Karoo, Kalahari, and Zambezi basins, whereas the previously identified enriched and depleted (upper) mantle sources of Karoo picrite suites (Mwenezi, Antarctica) were subordinate sources for flood basalts. We propose that the Luenha picrites record melting of a hot, chemically primitive mantle plume source that may have been rooted in the sub-African large low shear velocity province boundary and that such a source might have been the most significant magma source in the Karoo LIP.
DS202008-1405
2020
Heinonen, J.S.Kara, J., Vaisanen, M., Heinonen, J.S., Lahaye, Y., O'Brien, H., Huhma, H.Tracing arcologites in the Paleoproteroic era - a shift from 1.88 Ga calc-alkaline to 1.86 Ga high-Nb and adakite-like magmatism in central Fennoscandian shield.Lithos, in press available, 68p. PdfEurope, Fennoscandiaalkaline
DS202201-0018
2022
Heinonen, J.S.Heinonen, J.S., Spera, F.J., Bohrson, W.A.Thermodynamic limits for assimilation of silicate crust in primitive magmas.Geology, Vol. 50, 1, pp. 81-85.Mantlemagmatism

Abstract: Some geochemical models for basaltic and more primitive rocks suggest that their parental magmas have assimilated tens of weight percent of crustal silicate wall rock. But what are the thermodynamic limits for assimilation in primitive magmas? We pursue this question quantitatively using a freely available thermodynamic tool for phase equilibria modeling of open magmatic systems—the Magma Chamber Simulator (https://mcs.geol.ucsb.edu)—and focus on modeling assimilation of wall-rock partial melts, which is thermodynamically more efficient compared to bulk assimilation of stoped wall-rock blocks in primitive igneous systems. In the simulations, diverse komatiitic, picritic, and basaltic parental magmas assimilate progressive partial melts of preheated average lower, middle, and upper crust in amounts allowed by thermodynamics. Our results indicate that it is difficult for any subalkaline primitive magma to assimilate more than 20?30 wt% of upper or middle crust before evolving to compositions with higher SiO2 than a basaltic magma (52 wt%). On the other hand, typical komatiitic magmas have thermodynamic potential to assimilate as much as their own mass (59?102 wt%) of lower crust and retain a basaltic composition. The compositions of the parental melt and the assimilant heavily influence both how much assimilation is energetically possible in primitive magmas and the final magma composition given typical temperatures. These findings have important implications for the role of assimilation in the generation and evolution of, e.g., ultramafic to mafic trans-Moho magmatic systems, siliceous high-Mg basalts, and massif-type anorthosites.
DS2002-0639
2002
HeinrichHalter, W.E., Pettke, T., Heinrich, RothenRutishauserMajor to trace element analysis of melt inclusions by laser ablation ICP MS methods of quantification.Chemical Geology, Vol.183, 1-4, pp.63-86.MantleMelt, Geochemistry - techniques, Inductively Coupled Plasma- Mass
DS1960-0679
1966
Heinrich, .W.Heinrich, .W., Dahlem, D.H.Carbonatites and Alkalic Rocks of the Arkansaw River Area, Fremont county, Colorado.Mineralogical Society of India 4TH. VOLUME., PP. 37-44.United States, Colorado PlateauBlank
DS2002-0695
2002
Heinrich, C.A.Heinrich, C.A., Neubauer, F.Cu au Pb Zn Ag metallogeny of the Alpine Balkan Carpathian Dinaride geodynamic Province.Mineralium deposita, EuropeCopper, gold, lead, zinc, silver, Deposit - Dinaride area
DS200612-0559
2006
Heinrich, C.A.Heinrich, C.A.From fluid inclusion microanalysis to large scale hydrothermal mass transfer in the Earth's interior.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p.MantleMelt inclusions
DS1960-0680
1966
Heinrich, E.W.Heinrich, E.W.The Geology of CarbonatitesChicago: Rand Mcnally, 555P. INDIA PP. 553-570.United States, Canada, South Africa, Russia, Greenland, India, Brazil, EuropeBlank
DS1960-0731
1966
Heinrich, E.W.Quon, S.H., Heinrich, E.W.Abundance and Significance of Some Minor Elements in Carbonatites Calcites and Dolomites.India Mineralogical Society Volume, Edited By P.r.j. Naidu, Proceedings 4TH. GENERAL MEETING, PP. 29-36.IndiaRelated Rocks
DS1960-0840
1967
Heinrich, E.W.Heinrich, E.W., Dahlem, D.H.Carbonatites and Alkalic Rocks of the Arkansaw River Area, Fremont county, Colorado. Part 4. the Pinon Peak Breccia Pipes.American Mineralogist., Vol. 52, No. 5-6, PP. 817-831.United States, Colorado, Rocky MountainsDiatreme
DS1975-0659
1978
Heinrich, E.W.Alexander, D.H., Heinrich, E.W.Geology and Petrogenesis of the Mcclure Mountains Mafic Alkalic Carbonatitic Complex, Fremont County, Colorado.Geological Society of America (GSA), Vol. 10, No. 6, P. 245. (abstract.).United States, Colorado, Rocky MountainsCarbonatite
DS1975-0660
1978
Heinrich, E.W.Alexander, D.H., Heinrich, E.W.Geology and Petrogenesis of the Mcclure Mountain Mafic Alkalic Carbonatitic Complex, Fremont County, Colorado.Geological Society of America (GSA), Vol. 10, No. 6, P. 245. (abstract.).United States, Colorado, Rocky MountainsBlank
DS1981-0214
1981
Heinrich, E.W.Heinrich, E.W.Mineral Deposits of Alkalic RocksGeological Society of America (GSA), Vol. 13, No. 6, MARCH P. 281. (abstract.).GlobalBlank
DS1994-1534
1994
Heinrich, W.Schaaf, P., Heinrich, W.Geochemical, Strontium-neodymium isotopic and P T dat a on a central Mexican xenolith suite: crustal compositions.Mineralogical Magazine, Vol. 58A, pp. 803-804. AbstractMexicoXenboliths, San Luis Potosi field
DS200912-0808
2009
Heinrich, W.Watenphu, A., Wunder, B., Heinrich, W.High pressure ammonium bearing silicates: implications for nitrogen and hydrogen storage in Earth's mantle.American Mineralogist, Vol. 94, 2-3, pp. 283-292.MantleUHP
DS201504-0184
2015
Heinrich, W.Berryman, E.J., Wunder, B., Wirth, R., Rhede, D., Schettler, G., Franz, G., Heinrich, W.An experimental study on K and Na in corporation in dravitic tourmaline and insight into the origin of Diamondiferous tourmaline from the Kokchetav Massif, Kazakhstan.Contributions to Mineralogy and Petrology, Vol. 169, 19p.Russia, KazakhstanDiamondiferous tourmaline

Abstract: Tourmaline was synthesized in the system MgO-Al2O3-B2O3-SiO2-KCl-NaCl-H2O from an oxide mixture and excess fluid at 500-700 °C and 0.2-4.0 GPa to investigate the effect of pressure, temperature, and fluid composition on the relative incorporation of Na and K in dravitic tourmaline. Incorporation of K at the X-site increases with pressure, temperature, and KCl concentration; a maximum of 0.71 K pfu (leaving 0.29 X-vacant sites pfu) was incorporated into K-dravite synthesized at 4.0 GPa, 700 °C from a 4.78 m KCl, Na-free fluid. In contrast, Na incorporation depends predominately on fluid composition, rather than pressure or temperature; dravite with the highest Na content of 1.00 Na pfu was synthesized at 0.4 GPa and 700 °C from a 3.87 m NaCl and 1.08 m KCl fluid. All synthesized crystals are zoned, and the dominant solid solution in the Na- and K-bearing system is between magnesio-foitite [?(Mg2Al)Al6Si6O18(BO3)3(OH)3OH] and dravite [NaMg3Al6Si6O18(BO3)3(OH)3(OH)], with the dravitic component increasing with the concentration of Na in the fluid. In the K-bearing, Na-free system, the dominant solid solution is between magnesio-foitite and K-dravite [KMg3Al6Si6O18(BO3)3(OH)3(OH)], with the K-dravitic component increasing with pressure, temperature, and the concentration of K in the fluid. The unit-cell volume of tourmaline increases with K incorporation from 1555.1(3) to 1588.1(2) Å3, reflecting the incorporation of the relatively large K+ ion. Comparison of our results to the compositional data for maruyamaite (K-dominant tourmaline) from the ultrahigh-pressure rocks of the Kokchetav Massif in Kazakhstan suggests that the latter was formed in a K-rich, Na-poor environment at ultrahigh-pressure conditions near the diamond-stability field.
DS1991-0348
1991
Heinrichs, W.E.Davis, R.W., Heinrichs, W.E.Cross borehole seismic tomography applications to mineral developmentMining Engineering, Vol. 43, No. 8, August pp. 1051-1056GlobalGeophysics -seismic tomography, Overview
DS1989-0616
1989
Heinritzi, F.Heinritzi, F., Williams-Jones, A.E., Wood, S.A.Fluid inclusions in calcite and dolomite of the rare earth elements (REE)zone in the St. Honore carbonatite complex, QuebecGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A20. (abstract.)QuebecCarbonatite
DS1997-1004
1997
Heinsohn, W.D.Schmitz, M., Heinsohn, W.D., Schilling, F.R.Seismic gravity and petrological evidence for partial melt beneath the thickened Central Andean crustTectonophysics, Vol. 270, No. 3-4, March 15, pp. 313-South America, Bolivia, Chile, Brazil, AndesGeophysics - seismic, Mantle melt
DS2003-0862
2003
Heinson, G.Mahoney, S., James, P., Mauger, A., Heinson, G.Geologic and regolith mapping for mineral exploration in the Gawler Craton of SouthInternational Geoscience and Remote Sensing Symposium, Vol. 3, pp. III 1779-81. Ingenta 1034976078AustraliaRemote sensing
DS200412-1202
2003
Heinson, G.Mahoney, S., James, P., Mauger, A., Heinson, G.Geologic and regolith mapping for mineral exploration in the Gawler Craton of South Australia using Hyperion and other remote seInternational Geoscience and Remote Sensing Symposium, Vol. 3, pp. III 1779-81. Ingenta 1034976078AustraliaRemote sensing
DS200512-0416
2005
Heinson, G.Heinson, G., White, A.Electrical resistivity of the northern Australian lithosphere: crustal anisotropy or mantle heterogeneity?Earth and Planetary Science Letters, Vol. 232, 1-2, pp. 157-170.MantleGeophysics - seismics
DS200712-0668
2007
Heinson, G.Maier, R., Heinson, G., Thiel, S., Selway, K., Gill, R., Scroggs, M.A 3D lithospheric resistivity model of the Gawler Craton: southern Australia.Transactions of the Institution of Mining and Metallurgy, Vol. 116, 1, pp. 13-21.AustraliaGeophysics - resistivity
DS201312-0909
2013
Heinson, G.Thiel, S., Heinson, G.Electrical conductors in Archean mantle-result of plume interaction?Geophysical Research Letters, Vol. 40, 12, pp. 2947-2952.MantleHotspots
DS201612-2330
2016
Heinson, G.Robertson, K., Heinson, G., Thiel, S.Lithospheric reworking at the Proterozoic-Phanerozoic transition of Australia imaged using AuLAMP magnetotelluric data.Earth and Planetary Science Letters, Vol. 452, pp. 27-35.AustraliaGeophysics - magnetoctelluric
DS2002-0949
2002
Heintz, D.C.Linn, J.F., Heintz, D.C., Campbell, A.J., Devine, J.M., Mao, W.L., Shen, G.Iron nickel alloy in the Earth's coreGeophysical Research Letters, Vol. 29,10,May15,pp.108-MantleCore-mantle boundary
DS2002-0696
2002
Heintz, J.H.Heintz, J.H.Valuation of mineral interests in comdemnation casesSme Preprint, No. 02-074, 3p.United StatesLegal - brief overview, Economics - mineral interests, resources, reserves
DS2003-0573
2003
Heintz, M.Heintz, M., Vauchez, A., Assumpcao, M., Barruol, G., EgydioSilva, M.Shear wave splitting in SE Brazil: an effect of active or fossil upper mantle flow, orEarth and Planetary Science Letters, Vol. 211, 1-2, June 15, pp. 79-95.Brazil, south EastGeophysics - seismic anisotropy, crust mantle coupling
DS200412-0816
2003
Heintz, M.Heintz, M., Vauchez, A., Assumpcao, M., Barruol, G., EgydioSilva, M.Shear wave splitting in SE Brazil: an effect of active or fossil upper mantle flow, or both?Earth and Planetary Science Letters, Vol. 211, 1-2, June 15, pp. 79-95.South America, BrazilGeophysics - seismic anisotropy, crust mantle coupling
DS200512-0417
2005
Heintz, M.Heintz, M., De Bayle, E., Vauchez, A.Upper mantle structure of the South American continent and neighbouring oceans from surface wave tomography.Tectonophysics, Vol. 406, 1-2, pp. 115-139.South AmericaTomography
DS200512-0418
2005
Heintz, M.Heintz, M., Kennett, B.L.N.Continental scale shear wave splitting analysis: investigation of seismic anisotropy underneath the Australian continent.Earth and Planetary Science Letters, Advanced in press,AustraliaGeophysics - seismics, flow, coupling
DS200612-0049
2006
Heintz, M.Assumpcao, M., Heintz, M., Vauchez, A., Egydio Silva, M.Upper mantle anisotropy in SE and Central Brazil from SKS splitting: evidence of asthenospheric flow around a cratonic keel.Earth and Planetary Science Letters, Vol. 250, 1-2, pp. 224-240.South America, BrazilGeophysics - seismic, fast polarization
DS200612-0050
2006
Heintz, M.Assumpcao, M., Heintz, M., Vauchez, A., Silva, M.E.Upper mantle anisotropy in SE and Central Brazil from SKS splitting: evidence of asthenospheric flow around a cratonic keel.Earth and Planetary Science Letters, Vol.250, 1-2, pp. 224-240.South America, BrazilGeophysics - seismics
DS200612-0560
2006
Heintz, M.Heintz, M., Kennett, B.L.N.The apparently isotopic Australian upper mantle.Geophysical Research Letters, Vol. 33, 15, August 16, L15319AustraliaGeochronology
DS200812-0354
2008
Heintz, M.Fishwick, S., Heintz, M., Kennett, B.L.N., Reading, A.M., Yoshizawa, K.Steps in lithospheric thickness within eastern Australia, evidence from surface wave tomography.Tectonics, Vol. 27, TC 4009AustraliaTomography
DS200912-0292
2009
Heintz, M.Heintz, M., Kumar, V.P., Gaur, V.K., Priestly, K., Rai, S.S., Prakasam, K.S.Anisotropy of the Indian continental lithospheric mantle.Geophysical Journal International, Vol. 179, 3, pp. 1341-1360.IndiaGeodynamics
DS201012-0442
2010
Heintzman, R.Liaugaudas, G., Collins, A.T., Suhling, K., Davies, G., Heintzman, R.Luminescence - life time mapping in diamond.Journal of Physics Condensed Matter, Vol. 21, 36, pp. 364210-216.TechnologyDiamond crystallography
DS1990-0263
1990
Heinz, D.L.Campbell, A.J., Heinz, D.L., Davis, A.M.Melt partioning behaviour in high pressurehases of natural olivineEos, Vol. 71, No. 17, April 24, p. 527 Abstract onlyArizonaSan Carlos, Olivine
DS1991-0699
1991
Heinz, D.L.Heinz, D.L.Split decision on the mantleNature, Vol. 351, May 30, pp. 346-347GlobalGeophysics, Mantle
DS1991-0700
1991
Heinz, D.L.Heinz, D.L.Geophysics - split decision on the mantleNature, Vol. 351, No. 6325, May 30, p. 346GlobalMantle, Geophysics
DS1993-1562
1993
Heinz, D.L.Sweeney, J.S., Heinz, D.L.Melting of iron magnesium silicate perovskiteGeophysical Research Letters, Vol. 20, No. 9, May 7, pp. 855-858.GlobalMineralogy
DS1994-0753
1994
Heinz, D.L.Heinz, D.L., et al.high pressure melting of (Mg, Fe) SiO3 perovskiteScience, Vol. 264, April 8, pp. 279-281.GlobalPerovskite, magnesium, iron
DS1995-0784
1995
Heinz, D.L.Heinz, D.L.New phase for mantle researchNature, Vol. 374, No. 6519, March 16, p. 216.MantleGeophysics
DS1998-1332
1998
Heinz, D.L.Shen, G., Heinz, D.L.high pressure melting of deep mantle and core materialsReviews in Mineralogy, Vol. 37, pp. 369-96.MantleMineralogy, Geodynamics - boundary
DS2003-0819
2003
Heinz, D.L.Lin, J.F., Heinz, D.L., Mao, H., Hemley, R.J., Devine, J.M., Shen, G.Stability of magnesiowurstite in Earth's lower mantleProceedings of the National Academy of Sciences, USA, Vol. 100, 8, pp. 4405-8.MantlePetrology
DS200412-1138
2003
Heinz, D.L.Lin, J.F., Heinz, D.L., Mao, H., Hemley, R.J., Devine, J.M., Shen, G.Stability of magnesiowurstite in Earth's lower mantle.Proceedings of National Academy of Science USA, Vol. 100, 8, pp. 4405-8.MantlePetrology
DS1970-0092
1970
Heinz, L.A.Heinz, L.A.Afrique du SudUsine Nouv. Fr., Vol. 12, No. 50, PP. 101-105.South AfricaGeology
DS2003-0574
2003
Heinz, M.Heinz, M., Vauchez, A., Asuumpcao, M., Barruol, G., Egydio Silva, M.Shear wave splitting in SE Brazil: an effect of active or fossil upper mantle flow or both?Earth and Planetary Science Letters, Vol. 211, 1-2, pp. 79-95.BrazilBlank
DS1930-0109
1932
Heinz, R.Heinz, R.Ein Vorzeitlicher Traenkplatz Auf Den Diamant feldern Bei Luederitzbucht in Deutsch Suedwest Afrika und Seine Bedeutung Fuer die Geschnichte der Namibwueste.Geol. Deutsch. Fur Gesell., Vol. 84, P. 569. (abstract.).Southwest Africa, NamibiaDiamond Deposits
DS1930-0139
1933
Heinz, R.Heinz, R.Ein Vorzeitlicher Tranekplatz in der Namibwueste Bei Luderitzbucht ( Deutsch Suedwest Afrika). Mit Bemerkungen Zum Problem des Atlantis chen ozeans.Mitt. Geogr. Ges. Hamb., Vol. 43, PP. 267-302.Southwest Africa, NamibiaLittoral Diamond Placers
DS200612-0561
2006
Heir Majumder, C.A.Heir Majumder, C.A., Travis, B.J., Belanger, E., Richard, G., Vincent, A.P., Yuen, D.A.Efficient sensitivity analysis for flow and transport in the Earth's crust and mantle.Geophysical Journal International, Vol. 166, 2, pp. 907-922.MantleGeophysics - seismics
DS201112-0428
2011
Heir-Majumber, S.Heir-Majumber, S.Development of anisotropic mobility during two phase flow.Geophysical Journal International, In press availableMantleMagmatism - shapes
DS1994-0754
1994
Heirtzler, J.R.Heirtzler, J.R., Frawley, J.J.New gravity model for earth science studiesGsa Today, Vol. 4, No. 11, November pp. 269, 270.GlobalGeophysics -gravity
DS1989-0617
1989
Heise, H.Heise, H.Diamonds? take a look next doorCalgary Herald, Sat. April 1, 1 pgSaskatchewanNews item
DS1989-0618
1989
Heise, H.Heise, H.High tech helps diamond searchCalgary Herald, Sun. April 2, 1 pgSaskatchewanNews item
DS1991-1252
1991
Heiskanen, K.I.Ojakangas, R.W., Heiskanen, K.I.Early Proterozoic glaciogenic deposits: a North America -balticconnection?Minnesota Geological Survey, Information Circular No. 34, pp. 83-91Minnesota, RussiaGeomorphology, Glacial deposits
DS1998-0603
1998
Heisler, S.I.Heisler, S.I.Wiley's engineer's desk referenceWiley-Interscience, $ 75.00 second editionGlobalBook - ad, Mining engineering - manual
DS200512-0419
2005
Heister, L.E.Heister, L.E., Lesher, C.E.Mantle redox conditions in LIPs: constraints from the North Atlantic igneous province.Chapman Conference held in Scotland August 28-Sept. 1 2005, 1p. abstractMantleMantle plume, tectonics, rifting
DS200512-0620
2005
Heister, L.E.Lesher, C.E., Brown, E.L., Heister, L.E.Paleogene North Atlantic Igneous Province and the Iapetus connection.Chapman Conference held in Scotland August 28-Sept. 1 2005, 1p. abstractMantle, Europe, Iceland, GreenlandMantle plume
DS201212-0382
2012
Heister, T.Kronbichler, M., Heister, T., Bangeth, W.High accuracy mantle convection simulation through numerical methods.Geophysical Journal International, in press availableMantleConvection
DS201412-0149
2014
Heister, T.Cottaar, S., Heister, T., Rose, I., Unterborn, C.BurnMan: a lower mantle mineral physics toolkit.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, 4, pp. 1164-1179.MantleTechnology
DS1994-1253
1994
Heithersay, P.S.Muller, D., Heithersay, P.S., Groves, D.I.The shoshonite porphyry copper _ gold association in the Goonumbia district. New South WalesMineralogy and Petrology, Vol. 51, No. 2-4, pp. 299-322AustraliaCopper, gold, porphyry, Deposit -Goonumbia
DS200512-1153
2004
Heithersay, P.S.Vos, I.M.A., Bierlein, F.P., Heithersay, P.S., Lister, G.S.The 440 Ma event: a continental scale, mantle driven thermal phenomenon?Geological Society of America Abstracts, Vol. 74, pp. 141-145.MantleGeothermometry
DS1992-0626
1992
Heizler, M.T.Grunow, A.M., Dalziel, I.W.D., Harrison, T.M., Heizler, M.T.Structural geology and geochronology of subduction complexes along the margin of Gondwanaland: new dat a from the Antarctic Peninsula and southernmostAndesGeological Society of America (GSA) Bulletin, Vol. 104, No. 11, November pp. 1497-1514Andes, AntarcticaStructure, Geochronology
DS2000-1004
2000
Heizler, M.T.Wannamker, P.E., Hulen, J.B., Heizler, M.T.Early Miocene lamproite from the Colorado Plateau tectonic province, southeastern Utah, USAJournal of Volc. Geotherm. Res., Vol. 96, No. 3-4, Mar. pp. 175-90.Utah, Colorado PlateauLamproite
DS200712-0955
2007
Heizler, M.T.Schneider, D.A., Heizler, M.T., Bickford, M.E., Wortman, G.L., Condie, K.C., Perilli, S.Timing constraints of orogeny to cratonization: thermochronology of the Paleoproterozoic Trans-Hudson orogen, Manitoba and Saskatchewan, Canada.Precambrian Research, Vol. 153, 1-2, pp. 65-95.Canada, Manitoba, SaskatchewanGeothermometry
DS1985-0737
1985
Hejna, C.I.Wong, J., Koch, E.F., Hejna, C.I., Garbauskas, M.F.Atomic and microstructural characterization of metal impurities in synthetic diamondsJournal of Applied Physics, Vol. 58, No. 9, Nov. 1, pp. 3388-3393GlobalDiamond Morphology
DS1985-0738
1985
Hejna, C.L.Wong, J., Koch, E.F., Hejna, C.L., Garbausk, M.F.Atomic and Microstructural Characterization of Metal Impurities in Synthetic Diamonds.Journal of APPLIED PHYSICS, Vol. 58, No. 9, Nov. 1, PP. 3388-3393.GlobalSynthetic Diamond
DS201912-2824
2019
Hekinian, R.Shimizu, K., Saal, A.E., Hauri, E.H., Perfit, M.R., Hekinian, R.Evaluating the roles of melt rock interaction and partial degassing on the CO2/Ba ratios of MORB: implications of the CO2 budget in the Earth's depleted upper mantle.Geocimica et Cosmochimica Acta , Vol. 260, pp. 29-48.Mantlemelting

Abstract: Carbon content in the Earth's depleted upper mantle has been estimated in previous studies using CO2/Ba ratios of CO2 undersaturated depleted mid-ocean ridge basalt (D-MORB) glasses and melt inclusions. However, CO2/Ba ratios in CO2 undersaturated MORB may not necessarily record those of the mantle source, as they may be affected by (1) assimilation of Ba-rich plagioclase-bearing rocks in the oceanic crust and (2) CO2 degassing through partial degassing and mixing. In this study, we evaluate these effects on the CO2/Ba ratios as well as other volatile to refractory trace element ratios (H2O/Ce, F/Nd, Cl/K, and S/Dy) in D-MORBs using the compositions of olivine-hosted melt inclusions and glasses from the Siqueiros and Garrett transform faults. The Siqueiros and Garrett melt inclusions are CO2 undersaturated and highly depleted in incompatible trace elements, and their average CO2/Ba ratios show relatively large ranges of 90?±?34 and 144?±?53 respectively. A subset of melt inclusions in lavas from both transform faults show potential signatures of contamination by plagioclase-rich rocks, such as correlations between major elements contents (e.g., FeO, Al2O3, and MgO), and trace element ratios (e.g., Sr/Nd). We find that (1) assimilation fractional crystallization (AFC) of gabbro into D-MORB and (2) mixing between partial melts of gabbro and D-MORB can reproduce the observed range in Sr/Nd ratios as well as the general trends between major elements. However, we find that these processes had limited effects on the CO2/Ba ratio of the melt inclusions and it is unlikely that they can account for the observed range in the CO2/Ba ratio. On the other hand, while a partial degassing and mixing model can generate melts with large range of CO2/Ba ratios (as proposed by Matthews et al. (2017)), it cannot reproduce the Pearson correlation coefficients between CO2/trace element and 1/trace element ratios observed in the Siqueiros and Garrett melt inclusions. Instead, when analytical uncertainties on the elemental concentrations are considered, a model without partial degassing can adequately reproduce the majority of the observed range in CO2/Ba ratio and Pearson correlation coefficients. Hence, we postulate that the Siqueiros and Garrett melt inclusions are undegassed and use their average CO2/Ba ratios to estimate the Siqueiros and Garrett mantle source CO2 contents (21?±?2?ppm and 33?±?6?ppm respectively). We also evaluate the effects of shallow level crustal processes on H2O/Ce, F/Nd, Cl/K, and S/Dy ratios, and after which we filter those effects, we estimate the H2O, F, Cl and S contents in the mantle sources of the Siqueiros (40?±?8?ppm, 8?±?1?ppm, 0.22?±?0.04?ppm, and 113?±?3?ppm) and Garrett (51?±?9?ppm, 6?±?1?ppm, 0.27?±?0.07?ppm, and 128?±?7?ppm) melt inclusions.
DS200712-1017
2007
Helberger, D.V.Song, T-R.A., Helberger, D.V.A depleted destabilized continental lithosphere near the Rio Grande Rift.Earth and Planetary Science Letters, Vol. 262, 1-2, pp. 175-184.United States, Colorado PlateauTectonics
DS1993-0648
1993
Helden, G. vonHelden, G. von, Gotts, N.G., Bowers, M.T.Experimental evidence for the formation of fullerenes by collisional heating of carbon rings in the gas phaseNature, Vol. 363, No. 6424, May 6, pp. 60-63GlobalCVD.
DS201012-0786
2010
Helffich, G.Thompson, D.A., Bastow, I.D., Helffich, G., Kendall, J.M., Wookey, J., Snyder, D.B., Eaton, D.W.Precambrian crustal evolution: seismic constraints from the Canadian Shield.Earth and Planetary Science Letters, Vol. 297, 3-4, pp. 655-666.CanadaGeophysics - seismics
DS201112-1039
2011
Helffich, G.Thompson, D.A., Helffich, G., Bastow, L.D., Kendall, J-M., Wookey, J., Eaton, D.W., Snyder, D.B.Implications of a simple mantle transition zone beneath cratonic North America.Earth and Planetary Science Letters, Vol. 312, pp. 28-36.Canada, United StatesCraton, convective flow
DS1990-1576
1990
Helffrich, G.Wood, B., Helffrich, G.Earth sciences: internal structure of the earthNature, Vol. 344, No. 6262, March 8, p. 106GlobalMantle, Tectonics
DS1998-0604
1998
Helffrich, G.Helffrich, G., Kaneshima, S.Small scale lower mantle heteorgeneites as geochemical reservoirsMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 597.MantleGeochemistry, Subduction
DS2002-0697
2002
Helffrich, G.Helffrich, G.Chemical and seismological constraints on mantle heterogeneityPhilosophical Transactions, Royal Society of London Series A Mathematical, Vol.1800, pp. 2493-2506.MantleGeophysics - seismic, geochemistry
DS2002-0698
2002
Helffrich, G.Helffrich, G., Wiens, Vera, Barrientos, Shore ..A teleseismic shear wave splitting study to investigate mantle flow around South AfricaGeophysical Journal International, Vol.149,1,pp.F1-7., Vol.149,1,pp.F1-7.MantleGeophysics - seismics
DS2002-0699
2002
Helffrich, G.Helffrich, G., Wiens, Vera, Barrientos, Shore ..A teleseismic shear wave splitting study to investigate mantle flow around South AfricaGeophysical Journal International, Vol.149,1,pp.F1-7., Vol.149,1,pp.F1-7.MantleGeophysics - seismics
DS2003-0042
2003
Helffrich, G.Asencio, E., Knapp, J.H., Owens, T.J., Helffrich, G.Mapping fine scale heterogeneities within the continental mantle lithosphere beneathGeology, Vol. 31, 6, pp. 477-80.ScotlandTectonics
DS2003-0688
2003
Helffrich, G.Kaneshima, S., Helffrich, G.Subparallel dipping heterogeneities in the mid lower mantleJournal of Geophysical Research, Vol. 108, 5, ETG3 DOI 10.1029/2002JB001596MantleGeophysics - seismics
DS200412-0062
2003
Helffrich, G.Asencio, E., Knapp, J.H., Owens, T.J., Helffrich, G.Mapping fine scale heterogeneities within the continental mantle lithosphere beneath Scotland: combining active and passive sourGeology, Vol. 31, 6, pp. 477-80.Europe, ScotlandGeophysics - seismics Tectonics
DS200412-0951
2003
Helffrich, G.Kaneshima, S., Helffrich, G.Subparallel dipping heterogeneities in the mid lower mantle.Journal of Geophysical Research, Vol. 108, 5, ETG3 DOI 10.1029/2002 JB001596MantleGeophysics - seismics
DS200612-0562
2006
Helffrich, G.Helffrich, G.Heterogeneity in the mantle - its creation, evolution and destruction.Tectonophysics, Vol. 416, 1-4, April 5, pp. 23-31.MantleGeophysics - seismics
DS200612-1196
2006
Helffrich, G.Saalmann, Helffrich, G.Small scale seismic heterogeneity and mantle structure.Astronomy and Geophysics, Vol. 47, 1., pp.1.20-1.26.MantleGeophysics - seismics
DS200712-0110
2007
Helffrich, G.Brodholt, J.P., Helffrich, G., Trampert, J.Chemical versus heterogeneity in the lower mantle: the most likely role of anelasticity.Earth and Planetary Science Letters, Vol. 262, 3-4, Oct. 30, pp. 429-437.MantleGeochemistry
DS201112-0066
2011
Helffrich, G.Bastow, I.D., Thompson, D.A., Wookey, J., Kendall, J-M., Helffrich, G., Snyder, D.B., Eaton, D.W., Darbyshire, F.A.Precambrian plate tectonics: seismic evidence from northern Hudson Bay, Canada.Geology, Vol. 39, 1, pp. 91-94.Canada, Ontario, Quebec, Manitoba, Northwest TerritoriesGeophysics - seismics
DS201112-0772
2010
Helffrich, G.Pawlak, A., Eaton, D.W., Bastow, I.D., Kendall, J-M., Helffrich, G., Wookey, J., Snyder, D.Crustal structure beneath Hudson Bay from ambient noise tomography: implications for basin formation.Geophysical Journal International, Vol. 184, 1, pp. 65-82.Canada, Ontario, Quebec, James Bay LowlandsGeophysics -
DS201212-0291
2012
Helffrich, G.Helffrich, G.How light element addition can lower core liquid wave speed.Geophysical Journal International, in press availableMantleChemistry
DS201503-0136
2015
Helffrich, G.Bastow, I.D., Eaton, D.W., Kendall, J-M., Helffrich, G., Snyder, D.B., Thompson, D.A., Wookey, J., Darbyshire, F.A., Pawlak, A.E.The Hudson Bay lithospheric experiment ( HuBLE): insights into Precambrian plate tectonics and the development of mantle keels.Geological Society of London Special Publication: Continent formation through time., No. 389, pp. 41-67.Canada, Ontario, QuebecGeotectonics

Abstract: Hudson Bay Lithospheric Experiment (HuBLE) was designed to understand the processes that formed Laurentia and the Hudson Bay basin within it. Receiver function analysis shows that Archaean terranes display structurally simple, uniform thickness, felsic crust. Beneath the Palaeoproterozoic Trans-Hudson Orogen (THO), thicker, more complex crust is interpreted as evidence for a secular evolution in crustal formation from non-plate-tectonic in the Palaeoarchaean to fully developed plate tectonics by the Palaeoproterozoic. Corroborating this hypothesis, anisotropy studies reveal 1.8 Ga plate-scale THO-age fabrics. Seismic tomography shows that the Proterozoic mantle has lower wavespeeds than surrounding Archaean blocks; the Laurentian keel thus formed partly in post-Archaean times. A mantle transition zone study indicates ‘normal’ temperatures beneath the Laurentian keel, so any cold mantle down-welling associated with the regional free-air gravity anomaly is probably confined to the upper mantle. Focal mechanisms from earthquakes indicate that present-day crustal stresses are influenced by glacial rebound and pre-existing faults. Ambient-noise tomography reveals a low-velocity anomaly, coincident with a previously inferred zone of crustal stretching, eliminating eclogitization of lower crustal rocks as a basin formation mechanism. Hudson Bay is an ephemeral feature, caused principally by incomplete glacial rebound. Plate stretching is the primary mechanism responsible for the formation of the basin itself.
DS201603-0379
2015
Helffrich, G.Goncharov, A.F., Lobanov, S.S., Tan, X., Hohensee, G.T., Cahill, D.G., Lin, J-F., Thomas, S-M., Okuchi, T., Tomioka, N., Helffrich, G.Experimental study of thermal conductvity at high pressures: implication for the deep Earth's interior.Physics of the Earth and Planetary Interiors, Vol. 247, pp. 11-16.MantleExperimental Petrology

Abstract: Lattice thermal conductivity of ferropericlase and radiative thermal conductivity of iron bearing magnesium silicate perovskite (bridgmanite) - the major mineral of Earth’s lower mantle- have been measured at room temperature up to 30 and 46 GPa, respectively, using time-domain thermoreflectance and optical spectroscopy techniques in diamond anvil cells. The results provide new constraints for the pressure dependencies of the thermal conductivities of Fe bearing minerals. The lattice thermal conductivity of ferropericlase Mg0.9Fe0.1O is 5.7(6) W/(m * K) at ambient conditions, which is almost 10 times smaller than that of pure MgO; however, it increases with pressure much faster (6.1(7)%/GPa vs 3.6(1)%/GPa). The radiative conductivity of a Mg0.94Fe0.06SiO3 bridgmanite single crystal agrees with previously determined values for powder samples at ambient pressure; it is almost pressure-independent in the investigated pressure range. Our results confirm the reduced radiative conductivity scenario for the Earth’s lower mantle, while the assessment of the heat flow through the core-mantle boundary still requires in situ measurements at the relevant pressure-temperature conditions.
DS2001-0201
2001
Helffrich, G.R.Collier, J.D., Helffrich, G.R., Woodm B.J.Seismic discontinuities and subduction zonesPhysics of the Earth and Planetary Interiors, Vol. 127, No. 1-4, Dec. 1, pp. 35-49.MantleGeophysics - seismics, Subduction
DS2001-0466
2001
Helffrich, G.R.Helffrich, G.R., Wood, B.J.The Earth's mantleNature, No. 8636, Aug. 2, pp. 501-7.MantlePetrology
DS200612-0198
2006
Helg, U.Burkhard, M., Caritag, S., Helg, U., Robert Charrue, C., Soulaimani, A.Tectonics of the Anti-Atlas of Morocco.Comptes Rendus Geoscience, Vol. 338, 1-2, pp. 11-24.Africa, MoroccoTectonics
DS200612-0199
2006
Helg, U.Burkhard, M., Caritg, S., Helg, U., Robert-Charrue, C., Soulainmani, A.Tectonics of the Anti-Atlas of Morocco.Comptes Rendus Geoscience, Vol. 338, 1-2, pp. 11-24.Africa, MoroccoTectonics
DS1970-0926
1974
Helgren, D.M.Helgren, D.M., Butzer, K.W.Alluvial Terraces of the Lower Vaal River, South Africa: a Reappraisal and Reinvestigation: a Reply.Journal of Geology, Vol. 82, PP. 665-667.South AfricaGeomorphology
DS1975-0759
1978
Helgren, D.M.Helgren, D.M.Environmental Stratigraphy of the Relict Alluvia and Terraces Along the Lower Vaal River, South Africa.Palaeoecology of Africa And The Surrounding Islands, Vol. 10, PP. 163-170.South AfricaGeomorphology
DS1975-1071
1979
Helgren, D.M.Helgren, D.M.River of Diamonds 1979Chicago: University Chicago Department Geography Res. Paper., No. 185, 389P.South AfricaKimberley, Janlib, Kimberlite, Fluvial, Geomorphology
DS202111-1760
2021
Helibron, M.Bruno, H., Helibron, M., Strachen, R., Fowler, M., de MorrisonValeriano , C., Bersan, S., Moreira, H., Cutts, K., Dunlop, J., Almeida, R., Almeida, J., Storey, C.Earth's new tectonic regime at the dawn of the Paleozoic: Hf isotope evidence for efficient crustal growth and reworking in the Sao Francisco craton, Brazil.Geology, Vol. 49, 10, pp. 1214-1219. pdfSouth America, Brazilcraton

Abstract: A zircon Hf isotope data set from Archean and Paleoproterozoic magmatic and metasedimentary rocks of the southern São Francisco craton (Brazil) is interpreted as evidence of accretionary and collisional plate tectonics since at least the Archean-Proterozoic boundary. During the Phanerozoic, accretionary and collisional orogenies are considered the end members of different plate tectonic settings, both involving preexisting stable continental lithosphere and consumption of oceanic crust. However, mechanisms for the formation of continental crust during the Archean and Paleoproterozoic are still debated, with the addition of magmatic rocks to the crust being explained by different geodynamic models. Hf isotopes can be used to quantify the proportion of magmatic addition into the crust: positive ?Hf values are usually interpreted as indications of magmatic input from the mantle, whereas crust-derived rocks show more negative ?Hf. We show that the crust of the amalgamated Paleoproterozoic tectonostratigraphic terranes that make up the southern São Francisco craton were generated from different proportions of mantle and crustal isotopic reservoirs. Plate tectonic processes are implied by a consistent sequence of events involving (1) the generation of juvenile subduction-related magmatic arc rocks, followed by (2) collisional orogenesis and remelting of older crust, and (3) post-collisional bimodal magmatism.
DS200912-0334
2009
Helikkinen, P.Janik, T., Kozlovskaya, E., Helikkinen, P., Tliniemi, J.Evidence for preservation of crustal root beneath the Proterozoic Lapland-Kola orogen ( northern Fennoscandian shield) derived from P and S wave models.Journal of Geophysical Research, Vol. 114. B 6, B06308.Europe, Finland, Kola PeninsulaGeophysics - seismics
DS200412-1618
2003
Hell, A.Ramsay, W.R.H., Hell, A., Reinberger, G., Pooley, S.The geology, age, near surface features and mineralogy of the Merlin kimberlite field, Northern Territory, Australia.Geological Society of Australia Abstracts, Vol. 70, p. 54. 1p.Australia, Northern TerritoryDeposit overview - Merlin
DS2002-0700
2002
Hell, A.J.Hell, A.J.The stratigraphy and structural framework of the Merlin diamond field, Northern Territory, Australia.Geological Society of Australia Abstracts, Vol. 67, p. 332. abstract.Australia, Northern TerritoryStratigraphy, structure, Deposit - Merlin
DS2003-0575
2003
Hell, A.J.Hell, A.J., Ramsay, W.R.H., Rheinberger, G., Pooley, S.The geology, age, mineralogy and near surface features of the Merlin kimberlites8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractAustraliaKimberlite geology and economics, Deposit - Merlin
DS2003-1146
2003
Hell, A.J.Reddicliffe, T.H., Jakimowicz, J., Hell, A.J., Robins, J.A.The geology, mineralogy and near surface chacteristics of the Ashmore and Seppelt8ikc, Www.venuewest.com/8ikc/program.htm, Session 1 POSTER abstractAustraliaKimberlite geology and economics, Deposit - Ashmore, Seppelt
DS201810-2336
2018
Hell, J.V.Kankeu, B., Greiling, R.O., Nzenti, J.P., Ganno, S., Danguene, P.Y.E., Basshahak, J., Hell, J.V.Contrasting Pan-African structural styles at the NW margin of the Congo shield in Cameroon.Journal of African Earth Sciences, Vol. 146, pp. 28-47.Africa, Camerooncraton

Abstract: Field, microstructural, and anisotropy of magnetic susceptibility (AMS, magnetic fabrics) studies assessed the Pan-African deformational history and strain geometry at the southern margin of the Central African Fold Belt (CAFB) against the older, cratonic basement of the Congo Shield (CS). Reflected light microscopy and thermomagnetic studies supported the identification of magnetic minerals. Data cover a low angle thrust margin (Mbengis-Sangmelima area) in the east and high angle shear zones cutting the margin (Kribi area) in the west, at the Atlantic coast. In the CS basement units, magnetic anisotropy is generally higher than in the low grade Pan-African units. In the latter, early D1/D2 shortening produced a flat-lying magnetic foliation parallel with the regional trend of the belt, a shallow magnetic lineation, and mostly oblate fabrics. Subsequent D3 deformation is only of local importance in the Mbengis-Sangmelima area. The magnetic lineation shows distinct maxima in NNE-SSW direction, parallel with the low angle tectonic transport direction. In the Kribi area, the NNE-SSW trending Kribi-Campo shear zone (KCSZ) affected both older rocks and Pan-African high grade metapelites of the Yaoundé unit together with their basal thrust. The early planar fabric (S1) was overprinted during D2 folding under relatively high T conditions, and subsequent D3 wrenching. Magnetic fabrics document a progressive change from oblate towards prolate ellipsoids towards the KCSZ. Magnetic foliations with medium to steep dips curve into the N-S to NE-SW orientation of the KCSZ, lineations follow the same trend with shallow to medium plunges. This fabric implies that the KCSZ is a Pan-African strike-slip shear zone with a subordinate component of compression. Strike-slip tectonics in the west (KCSZ) and thrusting in the east imply N-S to NE-SW convergence during Pan-African terrane assembly against the present northern margin of the CS. In addition, the KCSZ may separate the CS from the São Francisco Craton in Brazil and thus be the northern part of a link connecting the CAFB to the West Congo Belt in the south. This putative Pan-African link separated the São Francisco Craton from the Congo Shield prior to Mesozoic Gondwana break-up.
DS1997-0499
1997
Hellam, A.Hellam, A., Wignall, P.Mass extinctions and their aftermathOxford University of Press, 320p. $ 85.00GlobalBook - ad, Extinctions - review of evidence
DS1920-0338
1927
Hellawell, A.Hellawell, A.The Story of the Diamond (1927)Min. Ind. Magazine (johannesburg), Vol. 5, SEPT. 21ST. P. 63; Oct. 10TH. PP. 135-136; Nov. 2ND.South AfricaHistory, Geology
DS200712-0220
2007
HellebrandDavies, G.R., Wasch, L., Van der Zwan, F., Morel, M.L.A., Nebel, Van Westrenen, Pearson, HellebrandThe origin of silica rich Kaapvaal lithospheric mantle.Plates, Plumes, and Paradigms, 1p. abstract p. A205.Africa, South AfricaDeposit - Kimberley
DS2002-0701
2002
Hellebrand, E.Hellebrand, E., Snow, J.E., Muhe, R.Mantle melting beneath Gakkel Ridge ( Arctic Ocean): abyssal peridotite spinel compositions.Chemical Geology, Vol.182, 2-4, Feb.15, pp.227-55.Arctic OceanPeridotites
DS200612-0623
2006
Hellebrand, E.Ionov, D.A., Hofmann, A.W., Merlet, C., Gurenko, A.A., Hellebrand, E., Montagnac, G., Gillet, P., PrikhodkoDiscovery of whitlockite in mantle xenoliths: inferences for water and halogen poor fluid and trace element residence in the terrestrial upper mantle.Earth and Planetary Science Letters, Vol. 244, 1-2, Apr. 15, pp. 201-207.MantleXenolith - mineralogy
DS200612-0650
2006
Hellebrand, E.Jung, S., Hellebrand, E.Trace element fractionation during high grade metamorphism and crustal melting - constraints from ion microprobe dat a of metapelitic, migmatitic and igneous garnets and implications for Sn Nd garnet chronologyLithos, Vol. 87, 1-4, April pp. 193-213.AfricaDamara Orogeny, geochronology Sm-Nd garnet chronology
DS200612-0938
2006
Hellebrand, E.Mocek, B., Hellebrand, E.REE concentrations of cpx and grt of mantle peridotites: new distribution coefficients from South Africa lherzolites.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 424. abstract only.Africa, South AfricaGeochemistry - REE
DS200612-1523
2006
Hellebrand, E.Weyer, S., Ionov, D.A., Hellebrand, E., Woodland, A.B., Brey, G.P.Iron isotope fractionation as indicator of mantle processes.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 16 abstract only.MantleGeochemistry - iron
DS200712-0737
2007
Hellebrand, E.Mocek, B., Hellebrand, E., Ionov, D.In situ measurements vs. lattice strain model calculations: distribution of REE between Grt and Cpx in garnet peridotites from Vitim ( Siberia).Plates, Plumes, and Paradigms, 1p. abstract p. A677.Russia, SiberiaVitim
DS201112-1009
2011
Hellebrand, E.Stracke, A., Snow, J.E., Hellebrand, E., Von der Handt, A., Bourdon, B., Birbaum, K., Gunther, D.Abyssal peridotite Hf isotopes identify extreme mantle depletion.Earth and Planetary Science Letters, Vol. 308, 3-4, pp. 359-368.Mantle, Europe, GreenlandGeochronology
DS201112-1010
2011
Hellebrand, E.Stracke, A., Snow, J.E., Hellebrand, E., Von der Handt, A., Bourdon, B., Birbaum, K., Guther, D.Abyssal peridotite Hf isotopes identify extreme mantle depletion.Earth and Planetary Science Letters, Vol. 308, 3-4, pp. 359-368.OceanGakkel Ridge
DS200912-0807
2009
Hellebrand, E.W.G.Wasch, L.J., Van der Zwan, F.M., Nebel, O., Morel, M.L.A., Hellebrand, E.W.G., Pearson, D.G., Davies, G.R.An alternative model for silica enrichment in the Kaapvaal subcontinental lithospheric mantle.Geochimica et Cosmochimica Acta, Vol. 73, 22, pp. 6894-6917.MantleMelting
DS1999-0465
1999
Heller, P.L.McMillan, M.E., Heller, P.L., Hoffower, BlackstoneIs there a northern boundary of the Colorado Plateau?Geological Society of America (GSA), Vol. 31, No. 7, p. 187. abstract.Alberta, WyomingTectonics
DS2003-0833
2003
Heller, P.L.Liu, S., Heller, P.L., Zhang, G.Mesozoic basin development and tectonic evolution of the Dabie Shan orogenic beltTectonics, Vol. 22, 4, August, 10.1029/2002TC001390ChinaTectonics, UHP
DS200412-1160
2003
Heller, P.L.Liu, S., Heller, P.L., Zhang, G.Mesozoic basin development and tectonic evolution of the Dabie Shan orogenic belt, central China.Tectonics, Vol. 22, 4, August, 10.1029/2002 TC001390ChinaTectonics UHP
DS1991-0701
1991
Hellfrich, G.Hellfrich, G., Brodholt, J.Relationship of deep seismicity to the thermal structure of subductedlithosphere.Nature, Vol. 353, Sept. 19, pp. 252-5.MantleSubduction, mantle structure, Geophysics - seismics
DS2002-0702
2002
Hellman, R.Hellman, R., Wood, S.A.Water rock interactions, ore deposits and environmental geochemistry: a tribute to David A. Crerar.http://gs.wustl.edu/publications/#SPS, SP #7, $80.GlobalBook - ore deposits, environment
DS200812-0805
2008
Helman, C.Nowicki, T., Helman, C., Gurney, J., Van Coller, B., Galloway, M., Smith, C., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.GSSA-SEG Meeting Held July, Johannesburg, 19 Power point slidesTechnologyEvaluation
DS2000-0404
2000
Helmberger, D.Helmberger, D., NI, S., Ritsema, J.Seismic evidence for ultralow velocity zones beneath Africa and eastern Atlantic.Journal of Geophysical Research, Vol. 105, No.B 10, Oct.10, pp.23865-78.AfricaGeophysics - seismics
DS2001-0769
2001
Helmberger, D.Melbourne, T., Helmberger, D.Mantle control of plate boundary deformationGeophysical Research Letters, Vol. 28, No. 20, Oct. 15, pp. 4003-6.MantleTectonics, Core mantle boundary
DS2002-0973
2002
Helmberger, D.Luo, S.N., Ni, S., Helmberger, D.Relationship of D structure with the velocity variations near the inner core boundaryGeophysical Research Letters, Vol. 29, 11, pp. 22- DOI 10.1029/2001GLO13907MantleGeophysics - seismics, Core-mantle boundary
DS200512-0778
2005
Helmberger, D.Ni, S., Helmberger, D., Tromp, J.Three dimensional structure of the African superplume from waveform modelling.Geophysical Journal International, Vol. 161, 2, pp. 283-294.AfricaGeophysics - seismics
DS200612-0563
2005
Helmberger, D.Helmberger, D., Lay, T., Ni, S., Gurnis, M.Deep mantle structure and the postperovskite phase transition.Proceedings of National Academy of Science USA, Vol. 102, no. 48, pp. 17257-283,MantleTectonics
DS200712-1051
2007
Helmberger, D.Sun, D., Tan, E., Helmberger, D., Gurnis, M.Seismological support for the metastable superplume model, sharp features, and phase changes within the lower mantle.Proceedings of National Academy of Sciences USA, Vol. 104, 22, pp. 9151-9155. IngentaMantleGeophysics - seismics
DS200812-1140
2008
Helmberger, D.Sun, D., Helmberger, D.Lower mantle tomography and phase mapping.Journal of Geophysical Research, Vol. 113, B10305.MantleGeophysics - seismics
DS200812-1141
2008
Helmberger, D.Sun, D., Helmberger, D.Lower mantle superdomes and plumes.Goldschmidt Conference 2008, Abstract p.A914.MantlePlume
DS200912-0293
2009
Helmberger, D.Helmberger, D., Sun, D., Lui, L., Tan, E., Gurnis, M.Review of large low shear veolocity provinces in the lower mantle.Goldschmidt Conference 2009, p. A520 Abstract.MantleCMB
DS200912-0741
2008
Helmberger, D.Sun, D., Helmberger, D.Lower mantle tomography and phase change mapping.Journal of Geophysical Research, Vol. 113, B10, B10305MantleGeophysics - seismics
DS201312-0376
2013
Helmberger, D.Helmberger, D., Chu, R., Leng, W., Gurnis, M.Hidden hotspot track beneath eastern United States.Goldschmidt 2013, AbstractUnited States, KentuckyKimberlite
DS201412-0128
2014
Helmberger, D.Chu, R., Helmberger, D.Lithospheric waveguide beneath the Midwestern United States; massive low-velocity zone in the lower crust.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, 4, pp. 1348-1362.United StatesGeophysics - seismics
DS1989-0874
1989
Helmberger, D.V.LeFevre, L.V., Helmberger, D.V.Upper mantle P velocity structure of the Canadian shieldJournal of Geophysical Research, Vol. 94, No. B 12, December 10, pp. 17, 749-17, 765CanadaMantle, Structure
DS1998-0605
1998
Helmberger, D.V.Helmberger, D.V., Wen, L., Ding, X.Seismic evidence that the source of the Iceland hotpsot lies at the core-mantle boundary.Nature, Vol. 396, No. 6709, Nov. 26, pp. 251-4.GlobalHot spots
DS1998-1345
1998
Helmberger, D.V.Sidorin, I., Gurnis, M., Helmberger, D.V., Ding, X.Interpreting D seismic structure using synthetic waveforms computed from dynamic models.Earth and Planetary Science Letters, Vol. 163, No. 1-4, Nov. pp. 31-41.MantleGeophysics - seismic, Slab
DS2001-0708
2001
Helmberger, D.V.Luo, S.N., NI, S., Helmberger, D.V.Evidence for a sharp lateral variation of velocity at the core mantle boundary from multipathed PKPab.Earth and Planetary Science Letters, Vol. 189, No. 3-4, July 15, pp. 155-64.MantleBoundary - inner core, outer core
DS2003-1010
2003
Helmberger, D.V.Ni, S., Helmberger, D.V.Seismological constraints on the South African superplume; could be the oldest distinctEarth and Planetary Science Letters, Vol. 206, 1-2, pp. 119-131.South AfricaGeophysics - seismics, Hot spots, plumes
DS2003-1011
2003
Helmberger, D.V.Ni, S., Helmberger, D.V.Ridge like lower mantle structure beneath South AfricaJournal of Geophysical Research, Vol. 108, 2, ESE 12.South AfricaTectonics - craton
DS200412-1431
2003
Helmberger, D.V.Ni, S., Helmberger, D.V.Ridge like lower mantle structure beneath South Africa.Journal of Geophysical Research, Vol. 108, 2, ESE 12.Africa, South AfricaTectonics - craton
DS200612-0564
2005
Helmberger, D.V.Helmberger, D.V., Sidao, Ni.Seismic modeling constraints on the South African super plume.American Geophysical Union, Geophysical Monograph, ed. Van der Hilst, Earth's Deep mantle, structure ...., No. 160, pp. 63-82.Africa, South AfricaGeophysics - seismics
DS201312-0895
2013
Helmberger, D.V.Sun, D., Helmberger, D.V., Jackson, J.M., Clayton, R.W.Rolling hills on the core-mantle boundary.Earth and Planetary Science Letters, Vol. 361, pp. 333-342.MantleCMB - structure
DS1998-0990
1998
Helmburger, D.Melbourne, T., Helmburger, D.Fine structure of the 410 Km discontinuityJournal of Geophysical Research, Vol. 103, No. 5, May 10, pp. 10091-103.MantleTectonics, Boundary - discontinuity
DS1970-0927
1974
Helme, N.Helme, N.Thomas Major CullinanJohannesburg: Mcgraw-hill, 271P., ILLLUS.South AfricaKimberley, Janlib, Biography
DS201212-0611
2012
Helmens, K.Rutter, N., Coronato, A.,Helmens, K., Rabassa, J., Zarate, M.Glaciations in North and South America from the Miocene to the last glacial maximum.Springer, Book adUnited States, Canada, South AmericaGeomorphology
DS200912-0294
2009
Helmer, J.Helmer, J.Russia's diamonds up for grabs. Outline of diamond mines and their potential ownerships.Waldman, March 14, 2p.RussiaEconomics
DS1860-1032
1898
Helmracker, R.Helmracker, R.On the Russian Diamond OccurrencesEngineering and Mining Journal, OCTOBER 28TH.RussiaHistory
DS1859-0085
1846
HelmreichenHelmreichen, Zu Brunfeld, V.Von.Uber das Geognostiche Vorkommen der Diamanten und Ihre Gewinnungsmethoden Auf der Serra Do Grao-mogol in der Provinz Minas-geraes in Brasilien.Wien: Bei Braumuller And Seidel, 74P.BrazilDiamond notable
DS1990-0682
1990
Helms, W.Helms, W.The diamond mining industry in northern Cape Province. (in German)Gluckauf, (in German), Vol. 126, No. 1-2, pp. 47-51South AfricaMining industry, Diamond
DS1986-0332
1986
Helmsaedt, H.Hall, D.C., Helmsaedt, H., Schulze, D.J.The Cross diatreme: a kimberlite in a young orogenic beltProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 30-32British ColumbiaPetrography
DS1999-0524
1999
HelmstaedtOlsen, H.K., Jensen, S.M., Schonwandt, H.K., HelmstaedtReview of diamond exploration in GreenlandNorth Atlantic Mineral Symposium, Sept., abstracts pp. 166-8.Greenland, Labrador, Ungava, QuebecExploration - brief review, History
DS1960-1108
1969
Helmstaedt, H.Gavasci, A.T., Helmstaedt, H.A Pyroxene Rich Garnet Peridotite Inclusion in an Ultramafic Breccia Dike at Moses Rock, Southeastern Utah.Journal of Geophysical Research, Vol. 74, PP. 6691-6695.United States, Utah, Colorado PlateauBlank
DS1960-1127
1969
Helmstaedt, H.Helmstaedt, H.Petrofabrics of Mafic and Ultramafic Inclusions from Kimberlite Pipes in Southeastern Utah and Northeastern Arizona.Eos, Vol. 50, No. 4, P. 345, (abstract.).United States, Arizona, Utah, Colorado PlateauBlank
DS1970-0528
1972
Helmstaedt, H.Helmstaedt, H., Anderson, O.L., Gavasci, A.T.Petrofabric Studies of Eclogite, Spinel-websterite, and SpinJournal of Geophysical Research, Vol. 77, PP. 4350-4365.United States, Utah, Arizona, Colorado PlateauBlank
DS1970-0713
1973
Helmstaedt, H.Helmstaedt, H., Doig, R.Eclogite Nodules from Kimberlite Pipes of the Colorado Plateau Samples of Subducted Franciscan Type Oceanic Lithosphere. #1International Kimberlite Conference FIRST EXTENDED ABSTRACT VOLUME., PP. 171-172.United States, Colorado Plateau, Colorado, Arizona, Utah, New MexicoDiatreme
DS1970-0928
1974
Helmstaedt, H.Helmstaedt, H.Overplating: a Major Factor in the Tectonics Evolution of The Colorado Plateau.Eos, Vol. 55, No. 4, P. 448, (abstract.).United States, Colorado PlateauBlank
DS1975-0103
1975
Helmstaedt, H.Helmstaedt, H., Doig, R.Eclogite Nodules from Kimberlite Pipes of the Colorado Plateau-samples of Subducted Franciscan Type Oceanic Lithosphere. #2Physics and Chemistry of the Earth, Vol. 9, PP. 95-111.United States, Colorado PlateauBlank
DS1975-0526
1977
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Type A- Type C Eclogite Transition in a Xenolith from the Moses Rock Diatreme Further Evidence for the Presence of Metamorphosed Ophiolites Beneath the Colorado Plateau.International Kimberlite Conference SECOND EXTENDED ABSTRACT VOLUME., United States, Colorado PlateauBlank
DS1975-0862
1978
Helmstaedt, H.Schulze, D.J., Helmstaedt, H., Cassie, R.M.Pyroxene Ilmenite Intergrowths in Garnet Pyroxenite Xenoliths from a New York Kimberlite and Arizona Latite.American Mineralogist., Vol. 63, PP. 258-265.United States, Appalachia, New York, Arizona, Colorado Plateau, Rocky MountainsPetrography
DS1975-1072
1979
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Garnet Clinopyroxene-chlorite Eclogite Transition in a Xenolith from Moses Rock: Further Evidence for Metamorphosed Ophiolites Under the Colorado Plateau.International Kimberlite Conference SECOND Proceedings, Vol. 2, PP. 357-365.United States, Colorado PlateauBlank
DS1975-1211
1979
Helmstaedt, H.Schulze, D.J., Helmstaedt, H.Garnet Pyroxenite and Eclogite Xenoliths from the Sullivan Buttes Latite, Chino Valley, Arizona.International Kimberlite Conference SECOND Proceedings, Vol. 2, PP. 318-329.GlobalKimberlite, Colorado Plateau, Rocky Mountains
DS1982-0269
1982
Helmstaedt, H.Helmstaedt, H.Possible Pre-kimberlite Serpentinization in Ultrabasic Xenoliths from Bultfontein and Jagersfontein Mines, South Africa.Proceedings of Third International Kimberlite Conference, TERRA COGNITA, ABSTRACT VOLUME., Vol. 2, No. 3, P. 210, (abstract.).South AfricaKimberlite, Texture, Mineralogy, Alteration
DS1982-0270
1982
Helmstaedt, H.Helmstaedt, H., Gurney, J.J.Kimberlites of Southern Africa- are they Related to Subduction Processes? #1Proceedings of Third International Kimberlite Conference, TERRA, Vol. 2, No. 3, PP. 272-273, (abstract.).South AfricaKimberlite, Genesis
DS1982-0513
1982
Helmstaedt, H.Raeside, R.P., Helmstaedt, H.The Ile Bizard Intrusion, Montreal, Quebec- Kimberlite or Lamprophyre?Canadian Journal of Earth Sciences, Vol. 19, No. 10, PP. 1996-2011.Canada, QuebecKimberlite, Xenolith, Breccia, Diatreme, Alnoite
DS1983-0215
1983
Helmstaedt, H.Erdmer, P., Helmstaedt, H.Eclogite from central Yukon: a record of subduction at the western Margin of ancient North America.Canadian Journal of Earth Sciences, Vol. 20, pp. 1389-1408.YukonEclogite, Subduction
DS1983-0528
1983
Helmstaedt, H.Raeside, R.P., Helmstaedt, H.The Ile Bizard Intrusion, Montreal, Quebec- Kimberlite or Lamprophyre? Discussion.Canadian Journal of Earth Sciences, Vol. 20, No. 9, PP. 1496-1498.Canada, QuebecGenesis, Kimberlite, Alnoite
DS1984-0336
1984
Helmstaedt, H.Hanish, M.B., Helmstaedt, H.Prekimberlitic Serpentinization of Peridotite Xenoliths, Bultfontein and Jagersfonetin Mines, R.s.a.- Implications for Upper Mantle Models.Geological Society of America (GSA), Vol. 16, No. 6, P. 529. (abstract.).South AfricaPetrography
DS1986-0355
1986
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Kimberlites and the mantle sample- can we decode theirgeotectonicmessage?Proceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 118-120South AfricaEclogites
DS1986-0356
1986
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Petrologic and geotectonic significance of eclogite xenoliths from Navajodiatremes, Colorado PlateauGeological Society of America, Vol. 18, No. 2, p. 116. AbstractUnited States, Colorado PlateauEclogite
DS1987-0270
1987
Helmstaedt, H.Hall, D.C., Helmstaedt, H., Schulze, D.J.The Cross diatreme, British Columbia, Canada: a kimberlite in a young orogenic belt #2Fourth International Kimberlite Conference, 26p. 7 figsBritish ColumbiaCanada, Diatreme
DS1988-0297
1988
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Eclogite facies ultramafic xenoliths from Colorado plateau diatremebreccias: comparison with eclogites in crustal environments, evaluation of thesubductionEclogites and eclogite-facies rocks, D.C. Smith ed., Elsevier, Dev. in, Chapter 7, pp. 387-450Colorado PlateauEclogite, *hypothesis impl. for ecl
DS1988-0616
1988
Helmstaedt, H.Schulze, D.J., Helmstaedt, H.Coesite-sanidine eclogites from kimberlite: products of mantle fractionation or subduction?Journal of Geology, Vol. 96, No. 4, pp. 435-443South AfricaEclogite, Coesite
DS1989-0572
1989
Helmstaedt, H.Hall, D.C., Helmstaedt, H., Schulze, D.J.The Cross diatreme, British Columbia, Canada: akimberlite in a young orogenic belt #1Geological Society of Australia Inc. Blackwell Scientific Publishing, No. 14, Vol. 1, pp. 97-108British ColumbiaDiatreme, Cross
DS1989-0619
1989
Helmstaedt, H.Helmstaedt, H., Schulze, D.J.Southern African kimberlites and their mantle sample:implications for Archean tectonics and lithosphereevolutionGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 1, pp. 358-368Southern AfricaTectonics
DS1989-0779
1989
Helmstaedt, H.King, J.E., Helmstaedt, H.Deformational history of an Archean fold belt, eastern Point Lake area, Slave Structural province, N.W.T.Canadian Journal of Earth Sciences, Vol. 26, No. 1, January pp. 106-118Northwest TerritoriesStructure, Archean
DS1990-1320
1990
Helmstaedt, H.Schulze, D.J., Helmstaedt, H.Garnet pyroxenites and eclogites from Chino Valley,Arizona, Lower crust or Upper mantle?Geological Society of America (GSA) Abstracts with programs, Cordilleran, Vol. 22, No. 3, p. 81Colorado Plateau, ArizonaEclogites, Mantle genesis
DS1991-0876
1991
Helmstaedt, H.Kirkley, M.B., Gurney, J.J., Harte, J.J., Helmstaedt, H.Geochemical correlations in Roberts Victor eclogitesProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, p. 224South AfricaGeochemistry, Eclogite xenoliths
DS1991-1197
1991
Helmstaedt, H.Moser, D.E., Krogh, T.E., Heaman, L.M., Hanes, J.A., Helmstaedt, H.The age and significance of Archean mid-crustal extension in the Kapuskasing uplift, Superior Province, CanadaGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 134OntarioTectonics, Kapuskasing uplift
DS1993-0598
1993
Helmstaedt, H.Gurney, J.J., Helmstaedt, H., Moore, R.O.A review of the use and application of mantle mineral geochemistry in diamond exploration.Pure and Applied Chemistry, Vol. 65, No. 12, December pp. 2423-2442.GlobalGeochemistry, Diamond exploration
DS1993-0701
1993
Helmstaedt, H.Hrabi, R.B., Grant, J.W., Godin, P.D., Helmstaedt, H., King, J.E.Geology of the Winter Lake supracrustal belt, central Slave Province, District of Mackenzie, N.W.T.Geological Survey Canada Paper, No. 93-1C, pp. 71-82Northwest TerritoriesWinter Lake, Regional geology
DS1994-0755
1994
Helmstaedt, H.Helmstaedt, H.The tectonic setting of diamond formation in diamond bearing kimberlitesThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Section Meeting Oct. 12, Vancouver, List of speakersGlobalTectonics
DS1994-0756
1994
Helmstaedt, H.Helmstaedt, H.Cadre geotectonique des depots -primaires de diamants....(in French)Seventh Colloque Annuel en Ressources Minerales, Universite du Quebec a, p. 2. abstract in FrenchGlobalTectonics
DS1994-1444
1994
Helmstaedt, H.Reif, C., Villeneuve, M., Helmstaedt, H.Discovery of an Archean carbonatite bearing alkaline complex in northern Slave Province: tectonic economicsNorthwest Territories 1994 Open House Abstracts, p. 53-54. abstractNorthwest TerritoriesCarbonatite
DS1995-0785
1995
Helmstaedt, H.Helmstaedt, H., Gurney, J.J.Geotectonic controls of primary diamond deposits: implications for areaselection.Journal of Geochemical Exploration, Vol. 52, pp. 125-144.Northwest TerritoriesDiamond exploration, Area selection
DS1998-1576
1998
Helmstaedt, H.White, D., Helmstaedt, H., Harrap, R., Thurston, P.The origin of our continent: LITHOPROBE seismic investigations in The western Superior TransectThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 90, No. 1017, Feb. pp. 78-82OntarioLithoprobe, Plate tectonics
DS2001-0467
2001
Helmstaedt, H.Helmstaedt, H., Gurney, J.J.Formation of the Archean Kaapvaal Province revisited: implications for birth and growth Diamondiferous rootSlave-Kaapvaal Workshop, Sept. Ottawa, 4p. abstractSouth AfricaCraton - Kaapvaal, Genesis
DS2002-0703
2002
Helmstaedt, H.Helmstaedt, H., Gurney, J.J.Hidden diamond deposits - role of tectonic and structural Craton analysis in integrated expl.approach.Society of Economic Geologists, Abstracts, pp. 27-28.Northwest TerritoriesTectonics - Slave Craton, Geodynamics
DS2002-1488
2002
Helmstaedt, H.Simmons, A., Helmstaedt, H.Petrography and geochemistry of the Nicholas Bay kimberlite, Lac de Gras kimberlite project, NWT.30th. Yellowknife Geoscience Forum, Abstracts Of Talks And Posters, Nov. 20-22, p. 61. abstractNorthwest TerritoriesGeochemistry
DS2003-0576
2003
Helmstaedt, H.Helmstaedt, H.Craton analysis in diamond exploration: why the Slave Province was a good place toGeological Association of Canada Annual Meeting, Abstract onlyNorthwest TerritoriesTectonics, tomography
DS2003-0882
2003
Helmstaedt, H.Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate referred from eclogite xenoliths in the ColoradoGeology, Vol. 31, 7, July pp. 589-92.Colorado PlateauCoesite, zircon, geochronology
DS2003-1021
2003
Helmstaedt, H.Nowicki, T.E., Crawford, B., Dyck, D., Carlson, J., McElroy, R., Helmstaedt, H.A review of the geology of kimberlite pipes of the Ekati property, Northwest8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractNorthwest TerritoriesGeology, Deposit - Ekati
DS2003-1108
2003
Helmstaedt, H.Pretorius, W., Chipley, D., Keyser, K., Helmstaedt, H.Direct determination of Os Ir Ru Pt and Re in kimberlites and other geologicalJournal of Analytical Atomic Spectrometry, Vol. 18, 4, pp. 302-9.GlobalGeochemistry
DS2003-1109
2003
Helmstaedt, H.Pretorius, W., Chipley, D., Kyser, K., Helmstaedt, H.Direct determination of trace levels of Os Ir Ru Pt and Re in kimberlite and otherJournal of Analytical Atomic Spectrometry, Vol. 18, 4, pp. 302-9.GlobalSpectrometry - trace elements
DS2003-1401
2003
Helmstaedt, H.Usui, T., Nakamura, E., Kobayashi, K., Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate inferred from eclogite xenoliths in the ColoradoGeology, Vol. 31, 7, July, pp. 589-592.Colorado Plateau, New Mexico, WyomingSubduction
DS200412-0817
2003
Helmstaedt, H.Helmstaedt, H.Craton analysis in diamond exploration: why the Slave Province was a good place to go.Geological Association of Canada Annual Meeting, Abstract onlyCanada, Northwest TerritoriesTectonics, tomography
DS200412-1237
2003
Helmstaedt, H.Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate referred from eclogite xenoliths in the Colorado Plateau.Geology, Vol. 31, 7, July pp. 589-92.United States, ColoradoCoesite, zircon, geochronology
DS200412-1450
2003
Helmstaedt, H.Nowicki, T.E., Crawford, B., Dyck, D., Carlson, J., McElroy, R., Helmstaedt, H., Oshust, P.A review of the geology of kimberlite pipes of the Ekati property, Northwest Territories, Canada8 IKC Program, Session 1, AbstractCanada, Northwest TerritoriesGeology Deposit - Ekati
DS200412-1587
2003
Helmstaedt, H.Pretorius, W., Chipley, D., Kyser, K., Helmstaedt, H.Direct determination of trace levels of Os Ir Ru Pt and Re in kimberlite and other geological materials using HR ICP Ms.Journal of Analytical Atomic Spectrometry, Vol. 18, 4, pp. 302-9.TechnologySpectrometry - trace elements
DS200412-2028
2003
Helmstaedt, H.Usui, T., Nakamura, E., Kobayashi, K., Maruyama, S., Helmstaedt, H.Fate of the subducted Farallon plate inferred from eclogite xenoliths in the Colorado Plateau.Geology, Vol. 31, 7, July, pp. 589-592.United States, ColoradoSubduction
DS200612-0565
2006
Helmstaedt, H.Helmstaedt, H.Cratons and structures, Canada's potential.Prospectors and Developers Association of Canada, March 1p. abstractCanadaTectonics
DS200612-1455
2006
Helmstaedt, H.Usui, T., Kobayashi, K., Nakamura, E., Helmstaedt, H.Trace element fractionation in deep subduction zones inferred from a lawsonite eclogite xenolith from the Colorado Plateau.Chemical Geology, in press available,United States, Colorado PlateauEclogite, subduction, Farallon plate, coesite
DS200612-1456
2006
Helmstaedt, H.Usui, T., Nakamura, E., Helmstaedt, H.Petrology and geochemistry of eclogite xenoliths from the Colorado Plateau: implications for the evolution of subducted oceanic crust.Journal of Petrology, Vol. 47, 5, pp. 929-964.United States, Colorado PlateauSubduction
DS200712-1103
2007
Helmstaedt, H.Usui, T., Kobayahsi, K., Nakamura, E., Helmstaedt, H.Trace element fractionation in deep subduction zones inferred from a lawsonite eclogite xenolith from the Colorado Plateau.Chemical Geology, Vol. 239, 3-4, April 30, pp. 336-351.United States, Colorado PlateauSubduction
DS200912-0013
2009
Helmstaedt, H.Arndt, N.T., Coltice, N., Helmstaedt, H., Gregorie, M.Origin of Archean subcontinental lithospheric mantle: some petrological constraints.Lithos, Vol. 109, 1-2, pp. 61-71.MantlePetrology
DS200912-0295
2009
Helmstaedt, H.Helmstaedt, H.Crust mantle revisited: the Archean Slave Craton, N.W.T., Canada.Lithos, In press available, 33p.Canada, Northwest TerritoriesSlave Craton, structure
DS201412-0352
2012
Helmstaedt, H.Helmstaedt, H., Pehrsson, S.J.Geology and tectonic evolution of the Slave Province, Canada: a post lithoprobe perspective.Tectonics, Geological Survey of Canada, Special Paper, 49, pp. 381-468.Canada, Northwest TerritoriesTectonics - lithoprobe
DS201412-0784
2014
Helmstaedt, H.Schulze, D.J., Flemming, R.L., Shepherd, P.M., Helmstaedt, H.Mantle derived guyanaite in a Cr-omphacite xenolith from Moses Rock diatreme, Utah.American Mineralogist, Vol. 99, pp. 1277-1283.United States, UtahMoses Rock diatreme
DS201508-0376
2015
Helmstaedt, H.Schulze, D.J., Davis, D.W., Helmstaedt, H., Joy, B.Timing of the Cenozoic " Great Hydration" event beneath the Colorado Plateau: Th-Pb dating of monazite in Navajo volcanic field metamorphic eclogite xenoliths.Geology, Vol. 43, pp. 727-730.United States, Colorado PlateauDiatremes - Moses Rock, Mule's Ear, Garnet Ridge, Cane Valley, Red Mesa, Buell Park, Green Knobs
DS201607-1352
2016
Helmstaedt, H.Helmstaedt, H.Diamond tectonics and geotectonics - how do they intersect in the Archean.IGC 35th., Session A Dynamic Earth 1p. AbstractGlobalTectonics
DS201708-1668
2017
Helmstaedt, H.Helmstaedt, H.The life cycle of Diamondiferous cratons - a leitmotif with infinite variations.11th. International Kimberlite Conference, OralMantlediamond genesis
DS201812-2799
2018
Helmstaedt, H.Davy, A.T., Smith, C.B., Helmstaedt, H., Jaques, A.L.PrefaceSociety of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, p. ixAustralia, India, Canada, Northwest Territories, Africa, Zimbabwedeposits - Argyle, Bunder, Diavik, Murowa
DS201812-2816
2018
Helmstaedt, H.Helmstaedt, H.Tectonic and structural controls on diamondiferous kimberlite and lamproite and their bearing on area selection for diamond exploration.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 1-48.Globaltechnology - diamond exploration
DS202108-1287
2021
Helmstaedt, H.Harte, B., Helmstaedt, H., Kopylova, M., Moore, A.E.John Gurney - a career of discovery and promotion of scientific knowledge.Lithos, Vol. 398-399, 1p. Africa, South Africa, GlobalTribute, obituary
DS202109-1470
2021
Helmstaedt, H.Helmstaedt, H., Pehrsson, S.J., Stubley, M.P.The Slave Province, Canada - geological evolution of an archean diamondiferous craton.Geological Association of Canada Bookstore, https://gac.ca/publications/bookstore Special Paper 51, 216p. Prices 42.50 member, $75.00 non-member isbn:978-1-897095-89-8Canada, Northwest TerritoriesCraton

Abstract: With its well-exposed geologic record from the Hadean Acasta gneiss complex through to Phanerozoic kimberlites, the Slave craton of northwestern Canada has long been a focus for research into early Earth evolution of both the crust and lithosphere. As a result, it has become one of the most extensively studied Archean cratons in the world. This multidisciplinary volume provides an authoritative overview of the Slave craton literally from the bottom up, integrating the nature of its lithosphere based on kimberlitic mantle samples with its upper crustal geology to provide a new model for its Archean assembly and cratonization. All aspects of Slave craton geology are covered, from the stratigraphy of its famous gold camps to the history of exploration and nature of its world-class diamondiferous kimberlite fields. Detailed and well-illustrated chapters cover its terranes and greenstone belts, magmatism, geophysical character, tectono-metamorphic evolution, and Paleoproterozoic marginal sequences. The book’s wealth of data and up-to-date bibliography provide a unique resource for understanding, researching and teaching Archean geology and subcrustal and cratonic evolution. It elegantly integrates diverse fields to provide one of the most comprehensive models for the craton and the protracted, multiphase formation of its diamond-bearing lithospheric root. (JK Note: the link above takes you to the GAC web site where Special Paper 51 can be purchased. Because the GAC only provides the abstract and a photo of the front page, I am providing a Table of Contents pdf.)
DS1988-0298
1988
Helmstaedt, H.H.Helmstaedt, H.H., Mott, J.A., Hall, D.C., Schulze, D.J., DixonStratigraphic and structural setting of intrusive breccia diatremes In the White River-Bulletin River area, southeastern British ColumbiaBritish Columbia Department of Mines, Geological Fieldwork 1987, Paper 1988-1, pp. 363-368British ColumbiaBlank
DS1989-0620
1989
Helmstaedt, H.H.Helmstaedt, H.H., Schulze, D.J.Evidence for subduction and spreading in the Archean rock record:implications for Archean tectonic style and the evolution of the subcontinental lithosphereLpi Technical Report, No. 89-05, pp. 42-44South AfricaTectonics, Age
DS1990-0683
1990
Helmstaedt, H.H.Helmstaedt, H.H., Schulze, D.J.Low temperature eclogites under the Colorado Plateau:fragments of Proterozoic or Mesozoic oceanic crust?Geological Society of America (GSA) Abstracts with programs, Cordilleran, Vol. 22, No. 3, p. 29Colorado PlateauEclogites, Mineralogy
DS1991-0702
1991
Helmstaedt, H.H.Helmstaedt, H.H.Early to mid-Tertiary inverted metamorphic gradient under the ColoradoPlateau: evidence from eclogite xenoliths in ultramafic microbreccias, Navajo volcanic fieldJournal of Geophysical Research, Vol. Paper # 91JB00284Colorado PlateauXenoliths, Subduction, eclogites
DS1991-0703
1991
Helmstaedt, H.H.Helmstaedt, H.H.Geotectonic considerations in diamond explorationnorthwest Territories Geology Division, Exploration overview 1991, November 1991, p. 24, 25. abstract onlyNorthwest TerritoriesTectonics, Diamonds
DS1991-0704
1991
Helmstaedt, H.H.Helmstaedt, H.H.Geotectonic controls of diamonds and kimberlites and their application To diamond explorationProceedings of Fifth International Kimberlite Conference held Araxa June 1991, Servico Geologico do Brasil (CPRM) Special, pp. 173-176United States, Colorado Plateau, South Africa, AustraliaCraton, mantle, Tectonics
DS1992-0696
1992
Helmstaedt, H.H.Helmstaedt, H.H.Primary diamond deposits: what controls their size, grade and locationGiant Ore Deposits, symposium held May 1992 at Queen's University, pp. 15-120GlobalDiamond deposits, Overview
DS1992-1702
1992
Helmstaedt, H.H.Wynne, P.J., Irving, E., Schulz, D.J., Hall, D.C., Helmstaedt, H.H.Paleomagnetism and age of three Canadian Rocky Mountain diatremesCanadian Journal of Earth Sciences, Vol. 29, No. 1, January pp. 35-47British ColumbiaDiatremes -Cross, Blackfoot, HP pipe, Paleomagnetics
DS1993-0649
1993
Helmstaedt, H.H.Helmstaedt, H.H.Natural diamond occurrences and tectonic setting of "primary" diamonddepositsProspectors and Developers Diamond Workshop, held March 27th, Toronto, 70pCanada, GlobalDiamond occurrences, Tectonic setting
DS1993-0650
1993
Helmstaedt, H.H.Helmstaedt, H.H.Natural diamond occurences and tectonic setting of primary diamonddepositsThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Professional Development Program, Techniques in exploration for, pp. 3-72GlobalDiamond exploration, Techniques
DS1993-0651
1993
Helmstaedt, H.H.Helmstaedt, H.H.Preservation and destruction of ancient Diamondiferous mantle roots:consequences for area selection in exploration for primary diamond depositsThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin) , Annual Meeting Abstracts approximately 10 lines, Vol. 86, No. 968, March ABSTRACT p. 71Northwest Territories, GlobalTectonics, Mantle source rocks
DS1993-0652
1993
Helmstaedt, H.H.Helmstaedt, H.H.Geotectonic controls of primary diamond deposits: implications for diamond exploration models and Archean tectonicsMid-continent diamonds Geological Association of Canada (GAC)-Mineralogical Association of Canada (MAC) Symposium ABSTRACT volume, held Edmonton May, pp. 7-10Northwest Territories, Wyoming, OntarioTectonics, Structure
DS1993-0653
1993
Helmstaedt, H.H.Helmstaedt, H.H., Gurney, J.J.Geotectonic controls on the formation of diamonds and their kimberlitic and lamproitic host rocks: applications to diamond exploration.Proceedings of the Fifth Kimberlite Conference held in Araxam Brasil, Vol. 2, pp. 236-250. 15p.Africa, North AmericaTectonics, diamond genesis, Craton
DS1994-0757
1994
Helmstaedt, H.H.Helmstaedt, H.H.Geotectonic controls of primary diamond deposits. Implication for area selection in diamond exploration.The Professional Association of Geologists and Geophysicists of Qu?bec (APGGQ) 1994, held Val'D'Or Aprl 13-15., 1p. abstractGlobalGeotectonics, Tectonics
DS1995-0059
1995
Helmstaedt, H.H.Armstrong, K.A., Roeder, P.L., Helmstaedt, H.H.The spinel mineralogy of the C14 kimberlite, Kirkland Lake, OntarioProceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 14-16.OntarioMineralogy -spinel, Deposit - C14 Kirkland Lake
DS1995-0786
1995
Helmstaedt, H.H.Helmstaedt, H.H., Gurney, J.J.Kimberlites -why when and where? a heirarchy of geotectonic controlsProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 233-235.South Africa, Northwest TerritoriesGeotectonics, Craton
DS1997-0040
1997
Helmstaedt, H.H.Armstrong, K.A., Roeder, P.L., Helmstaedt, H.H.Composition of spinels in the Carbon 14 kimberlite, Kirkland Lake Ontario.Russian Geology and Geophysics, Vol. 38, No. 2, pp. 454-466.OntarioGeochemistry, Deposit -C 14
DS1997-0500
1997
Helmstaedt, H.H.Helmstaedt, H.H., Gurney, J.J.Geodynamic controls of kimberlites - what are the roles of hotspot and plate tectonics?Russian Geology and Geophysics, Vol. 38, No. 2, pp. 492-508.MantleHotspots, Plate tectonics
DS1998-0067
1998
Helmstaedt, H.H.Bailey, L.M., Helmstaedt, H.H., Peterson, R., MandarinoMicrodiamonds and indicator minerals from a talc schist rock, FrenchGuiana.7th International Kimberlite Conference Abstract, pp. 37-39.GlobalMetakimberlites, Paramaca series
DS1998-0585
1998
helmstaedt, H.H.Harrap. R.M., helmstaedt, H.H.Reasoning across deep time: formal reasoning examination of Archeantectonics.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A396.GlobalTectonics, Crustal assembly
DS1998-0606
1998
Helmstaedt, H.H.Helmstaedt, H.H.The Archean Slave province: regional tectonic framework for Canada's first economic primary diamond deposits.Geological Society of America (GSA) Annual Meeting, abstract. only, p.A245.Northwest TerritoriesTectonics - overview, Slave Province setting
DS1998-0607
1998
Helmstaedt, H.H.Helmstaedt, H.H., Harrap, R.M.Tectonic aspects of the kimberlite diamond upper mantle sample connection:does a coherent model evolve?7th International Kimberlite Conference Abstract, pp. 331-5.Ontario, Manitoba, Northwest TerritoriesCraton, subduction, Petrology, Lithoprobe, geophysics - seismics, SNORCLE.
DS1998-1267
1998
Helmstaedt, H.H.Ruiz, J., McCandless, T.E., Helmstaedt, H.H.Eclogites from the Colorado Plateau: a Phanerozoic record of subduction beneath North America.7th. Kimberlite Conference abstract, pp. 757-9.Colorado PlateauSubduction, Eclogites
DS1999-0303
1999
Helmstaedt, H.H.Helmstaedt, H.H., Olesen, H.K., Jensen, S., SchonwandtThe diamond potential of the northern margin of the North Atlantic Cratonin West Greenland.North Atlantic Mineral Symposium, Sept., abstracts pp. 169-70.Greenland, Labrador, Ungava, QuebecExploration - brief review, Craton
DS1999-0615
1999
Helmstaedt, H.H.Ruiz, J., McCandless, T.E., Helmstaedt, H.H.Re Os model ages for eclogite xenoliths from the Colorado Plateau, USA7th International Kimberlite Conference Nixon, Vol. 2, pp. 736-40.Colorado Plateau, New MexicoGeochronology, subduction, diatreme, Moses Rock, Garnet Ridge, Mule Ear
DS2003-0299
2003
Helmstaedt, H.H.Crawford, J., Helmstaedt, H.H.Comparative study of hypabyssal kimberlite from four locations within the Slave8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractNorthwest TerritoriesDeposit - Finlay, Muskox, Rich, Jean
DS2003-1105
2003
Helmstaedt, H.H.Pretorius, W., Helmstaedt, H.H., Kyser, K.Platinum group element geochemistry of kimberlitic rocks - a window into the nature of8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, POSTER abstractUnited States, Canada, Greenland, Somerset Island, ChinaBlank
DS2003-1473
2003
Helmstaedt, H.H.White, D.J., Musacchio, G., Helmstaedt, H.H., Harrap, R.M., Thurston, P.C.Images of lower crustal oceanic slab: direct evidence for tectonic accretion in theGeology, Vol. 31, 11, pp. 997-1000.OntarioSubduction - not specific to diamonds
DS200412-0386
2003
Helmstaedt, H.H.Crawford, J., Helmstaedt, H.H.Comparative study of hypabyssal kimberlite from four locations within the Slave Craton.8 IKC Program, Session 7, POSTER abstractCanada, Northwest TerritoriesKimberlite petrogenesis, Finlay, Muskox, Rich, Jean
DS200412-1584
2003
Helmstaedt, H.H.Pretorius, W.,Helmstaedt, H.H., Kyser, K.Platinum group element geochemistry of kimberlitic rocks - a window into the nature of the Diamondiferous mantle.8 IKC Program, Session 7, POSTER abstractUnited States, Canada, Nunavut, Somerset IslandKimberlite petrogenesis
DS200412-2109
2003
Helmstaedt, H.H.White, D.J., Musacchio, G., Helmstaedt, H.H., Harrap, R.M., Thurston, P.C., Van der Velden, A., Hall, K.Images of lower crustal oceanic slab: direct evidence for tectonic accretion in the Archean western Superior Province.Geology, Vol. 31, 11, pp. 997-1000.Canada, OntarioSubduction - not specific to diamonds
DS201012-0254
2010
Helmstaedt, H.H.Gurney, J.J., Helmstaedt, H.H., Richardson, S.H., Shirey, S.B.Diamonds through time.Economic Geology, Vol. 105, 3, pp. 689-712.GlobalHistory of diamond genesis
DS201012-0729
2010
Helmstaedt, H.H.Smith, E.M., Helmstaedt, H.H., Flemming, R.I.Survival of the brown colour in diamond during storage in the subcontinental lithospheric mantle.The Canadian Mineralogist, Vol. 48, 3, pp. 571-582.Canada, Northwest TerritoriesDiamond morphology - Ekati
DS201012-0730
2010
Helmstaedt, H.H.Smith, E.M., Helmstaedt, H.H., Flemming, R.I.Survival of the brown colour in diamond during storage in the subcontinental lithospheric mantle.The Canadian Mineralogist, Vol. 48, 3, pp. 571-582.Canada, Northwest TerritoriesDiamond morphology - Ekati
DS201112-0429
2010
Helmstaedt, H.H.Helmstaedt, H.H., Gurney, J.J., Richardson, S.H.Ages of cratonic diamond and lithosphere evolution: constraints on Precambrian tectonics and diamond exploration.The Canadian Mineralogist, Vol. 48, 6, pp. 1385-1408.Canada, GlobalGeochronology, craton roots, UHP
DS201212-0274
2012
Helmstaedt, H.H.Gurney, J.J., Helmstaedt, H.H.Type Iia diamonds and their enhanced ecnomic significance.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalDiamond - Iia
DS201212-0292
2012
Helmstaedt, H.H.Helmstaedt, H.H.Tectonic relationships between cratonic and ultra high pressure (UHP) diamond implications for craton formation and stabilization.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalUHP
DS201312-0377
2013
Helmstaedt, H.H.Helmstaedt, H.H.Tectonic relationships between E-type cratonic and ultra-high-pressure (UHP) diamonds: implications for craton formation and stabilization.Proceedings of the 10th. International Kimberlite Conference, Vol. 1, Special Issue of the Journal of the Geological Society of India,, Vol. 1, pp. 45-58.MantleUHP
DS1993-0599
1993
Helmstaedt, J.Gurney, J.J., Helmstaedt, J., Moore, R.O.A review of the use and application of mantle geochemistry in diamondexploration.Pure and Applied Geochemistry, Vol. 65, No. 12, pp. 2423-2442.MantleRoots, Geochemistry
DS1987-0655
1987
Helmsteadt, H.Schultz, D.J., Helmsteadt, H., Carmichael, D.M.Hydrated pyroxenite xenoliths from Navajo diatremes, ColoradoPlateau:pressure temperature estimates and metasomatic reactions in the mantle wedge above tGeological Society of America, Vol. 19, No. 7 annual meeting abstracts, p.835. abstracColorado PlateauDiatreme
DS1992-0697
1992
Helmsteadt, H.Helmsteadt, H.Cratons and diamondsNorthwest Territories Geoscience Forum held November 25, 26th. 1992, AbstractNorthwest TerritoriesTectonics, Diamonds
DS1995-1136
1995
Helmsteadt, H.MacLachlan, K., Helmsteadt, H.Geology and geochemistry of an Archean mafic dike complex in the Chan Formation -revised plate tectonicsCanadian Journal of Earth Sciences, Vol. 32, No. 5, May pp. 614-630Northwest TerritoriesYellowknife greenstone belt, Tectonics
DS200712-0425
2007
Helmsteadt, H.H.Helmsteadt, H.H.Geotectonic setting of Slave Province diamond deposits.Geological Association of Canada, Gac-Mac Yellowknife 2007, May 23-25, Volume 32, 1 pg. abstract p.39.Canada, Northwest TerritoriesType 3 province
DS200912-0296
2009
Helmsteadt, H.H.Helmsteadt, H.H., Gurney, J.J., Richardson, S.H.Diamond ages and lithosphere evolution: applications to diamond exploration.GAC/MAC/AGU Meeting held May 23-27 Toronto, Abstract onlyTechnologyDiamond genesis and craton evolution
DS201112-0053
2011
HelmyBallhaus, C., Laurenz, V., Fonseca, R., Munker, C., Albarede, Rohrbach, Schmidt, Jochum, Stoll, Weis, HelmyLate volatile addition to Earth.Goldschmidt Conference 2011, abstract p.475.MantleW and Cr elements
DS202005-0717
2020
Helmy, H.H.Abdel Halim, A.H., Helmy, H.H., Elhaddad, M.A., El-Mahallawi, M., Mogessie, A.Petrology of a Neoproteroxoic mantle peridotite-chromitite association from Abu Dahr area, eastern Egypt Desert, Egypt: infiltration of boninitic melt in highly depleted harzburgite.Journal of African Earth Sciences, Vol. 165, 18p. PdfAfrica, EgyptBoninite

Abstract: Peridotites of Abu Dahr represent the main litho-unit of a Neoproterozoic dismembered ophiolite sequence and are among the best-preserved and well-exposed mantle rocks in South Eastern Desert of Egypt. Here, we present new geochemical and mineral chemical data for peridotites and associated pyroxenites and for chromitites and their platinum-group minerals to constrain their petrogenesis and geotectonic setting. The Abu Dahr ophiolite mantle section consists mainly of harzburgites, cut by pyroxenite dykes and containing dunite-chromitite lenses. The harzburgites are composed of olivine, orthopyroxene, spinel and minor clinopyroxene (?1.0 vol %) and amphibole. Olivine from harzburgites is highly magnesian (Fo 91-93) and Cr-spinel shows a wide-range of Cr2O3 and Al2O3 contents. The enstatite component of orthopyroxene decreases from harzburgite (En = 90-91) to orthopyroxenite (En = 84-87). Amphiboles are represented by magnesiohornblende and tschermakite. The chromitites are massive to disseminated and composed of magnesiochromite with high Cr# (83-93) and Mg# (66-79), and low TiO2 (<0.1 wt%) content. Solid inclusions in chromite include olivine, orthopyroxene and hornblende. Laurite (RuS2) is the most common PGM detected in the investigated chromitite samples and forms micrometer-size inclusions in fresh chromite. Various Ni-sulfides are found both in fresh chromite and along serpentine veinlets. Harzburgites have a refractory composition with a very low Al2O3 (0.4-0.8 wt%) and CaO (0.2-1.6 wt%) contents and high bulk-rock Mg# (89-92). Geochemical data suggest that the Abu Dahr peridotites are highly depleted SSZ peridotites formed in a forearc mantle wedge setting by high degrees of hydrous partial melting and emplaced as a result of the collision of the intra-oceanic arc with the Beitan gneisses. The podiform chromitites and orthopyroxenites were formed due to impregnation of mantle wedge harzburgites by boninitic melt. The highly depleted nature of the harzburgite is responsible for the small reserves of chromite ore at Abu Dahr and in the South Eastern Desert in general.
DS201312-0053
2013
Helmy, H.M.Ballhaus, C., Laurenz, V., Munker, C., Fonseca, R.O.C., Albarede, F., Rohrbach, A., Lagos, M., Schmidt, M.W., Jochum, K-P., Stoll, B., Weis, U., Helmy, H.M.The U /Pb ratio of the Earth's mantle - a signature of late volatile addition.Earth and Planetary Interiors, Vol. 362, pp. 237-245.MantleMelting
DS1930-0163
1934
Helsberger, H.Helsberger, H.Kann der Diamant Kosmogenetischer Ursprung Sein?Zeits. Prakt. Geol., Vol. 42, PP. 124-125.Southwest Africa, NamibiaDiamond, Genesis, Meteoritic, Brukkaros
DS1984-0352
1984
Helstaedt, H.Helstaedt, H., Gurney, J.J.Kimberlites of Southern Africa- are they Related to Subduction Processes? #2Proceedings of Third International Kimberlite Conference., Vol. 1, PP. 425-434.South Africa, Botswana, LesothoDistribution, Kimberlite, Genesis, Xenolith
DS200812-0046
2008
Helstaedt, H.Arndt, N.T., Coltice, N., Helstaedt, H., Gregoire, M.Origin of Archean subcontinental lithospheric mantle: some petrological constraints.Lithos, In press available 47p.CanadaArchean - craton
DS1994-0758
1994
Helterbrand, J.D.Helterbrand, J.D., Cressie, N.Universal cokriging under intrinsic coregionalizationMathematical Geology, Vol. 26, No. 2, pp. 205-236GlobalGeostatistics, Cokriging
DS200512-0420
2005
Hemant, K.Hemant, K., Maus, S.Why no anomaly is visible over most of the continent ocean boundary in the global crustal magnetic field.Physics of the Earth and Planetary Interiors, Vol. 149, 3-4, April 15, pp. 321-333.MantleGeophysics - magnetics
DS200612-1090
2006
Hemant, K.Pilkington, M., Snyder, D.B., Hemant, K.Weakly magnetic crust in the Canadian Cordillera.Earth and Planetary Science Letters, Vol. 248, 1-2, Aug. 15, pp. 461-470.Canada, British ColumbiaGeophysics - magnetics
DS200712-0426
2007
Hemant, K.Hemant, K., Thebault, E., Mandea, M., Ravat, D., Maus, S.Magnetic anomaly map of the world: merging satellite, airborne, marine and ground based magnetic dat a sets.Earth and Planetary Science Letters, Vol. 260, 1-2, pp. 56-71.GlobalMap - magnetics
DS200712-0427
2007
Hemant, K.Hemant, K., Thebault, E., Mandea, M., Ravat, D., Maus, S.Magnetic anomaly map of the world: merging satellite, airborne, marine and ground based magnetic dat a sets.Earth and Planetary Science Letters, Vol. 260, 1-2, pp. 56-71.GlobalMap - magnetics
DS201312-0539
2013
Hemawan, K.Liang, Q., Meng, Y., Yan, C., Krasnicki, S., Lai, J., Hemawan, K., Shu,H., Popov, D., Yu,T., Yang, W., Mao, H., Hemley, R.Developments in synthesis, characterization, and application of large high-quality CVD single crystal diamond.Journal of Superhard Materials, Vol. 35, 4, pp. 195-213.TechnologyDiamond synthetics
DS1990-1226
1990
Hemingway, B.S.Richet, P., Robie, R.A., Hemingway, B.S., Beuville, D., Richard, G.Thermodynamic and melting properties of pyrope (Mg3Al2Si3O12)Terra, Abstracts of Experimental mineralogy, petrology and, Vol. 2, December abstracts p. 93AlpsMantle, Pyrope
DS1991-1708
1991
Hemingway, B.S.Tequil, C., Robie, R.A., Hemingway, B.S., Neuville, D.R., Richet, P.Melting and thermodynamic properties of pyrope (MgsAl2Si3O12)Geochim. et Cosmochimica Acta, Vol. 55, pp. 1005-1010GlobalMineralogy -experimental, Pyrope
DS2001-0036
2001
Hemley, R.Angel, R.J., Frost, D.J., Ross, N.L., Hemley, R.Stabilities and equations of state of dense hydrous magesium silicatesPhysics of the Earth and Planetary Interiors, Vol. 127, No. 1-4, Dec. 1, pp. 181-96.MantleMineralogy - silicates, Subduction - geodynamics, rheology
DS2003-0026
2003
Hemley, R.Araujo, D.P., Gaspar, J.C., Fei, Y., Hauri, E.H., Hemley, R., Bulanova, G.P.Mineralogy of diamonds from the Juin a Province, Brazil8ikc, Www.venuewest.com/8ikc/program.htm, Session 3, POSTER abstractBrazilDiamonds
DS201312-0539
2013
Hemley, R.Liang, Q., Meng, Y., Yan, C., Krasnicki, S., Lai, J., Hemawan, K., Shu,H., Popov, D., Yu,T., Yang, W., Mao, H., Hemley, R.Developments in synthesis, characterization, and application of large high-quality CVD single crystal diamond.Journal of Superhard Materials, Vol. 35, 4, pp. 195-213.TechnologyDiamond synthetics
DS1989-0425
1989
Hemley, R.J.Finger, L.W., Ko, J., Hazen, R.M., Gasparik, T., Hemley, R.J.Crystal chemistry of phase B and an anhydrous analogue:implications for water storage in the upper mantleNature, Vol. 341, No. 6238, Sept. 14, pp. 40-142GlobalMantle, Geochemistry
DS1990-1199
1990
Hemley, R.J.Prewitt, C.T., Carlson, R., Hemley, R.J.Chemical evolution of the mantleAmerican Geophysical Union (AGU)/MSA Meeting to be held May 29-June 1, Session MO2-GlobalMantle, Tectonics
DS1991-0705
1991
Hemley, R.J.Hemley, R.J., Kubicki, J.D.Mineral physics: deep mantle meltingNature, Vol. 349. No. 6307, January 24, p. 283GlobalMantle, Physics
DS1991-1047
1991
Hemley, R.J.Mao, H.K., Hemley, R.J.Optical transitions in diamond at ultrahigh pressuresNature, Vol. 351, No. 6329, June 27, pp. 721-724GlobalDiamond morphology, Spectroscopy
DS1992-1478
1992
Hemley, R.J.Stixrude, L., Hemley, R.J., Fei, Y., Mao, H.K.Thermoeleasticity of silicate perovskite and magnesiowustite and stratification of the earth's mantleScience, Vol. 257, August 21, pp. 1099-1101MantleStratification, Perovskite
DS1995-0787
1995
Hemley, R.J.Hemley, R.J.Chemistry of the deep mantle and coreGeological Society of America (GSA) Abstracts, Vol. 27, No. 6, abstract p. A 94.MantleGeochemistry
DS1995-0957
1995
Hemley, R.J.Kingma, K.J., Cohen, R.E., Hemley, R.J., Mao, H.K.Transformation of stishovite to a denser phase at lower mantle pressuresNature, Vol. 374, No. 6519, March 16, p. 243-245.MantleCoesite association
DS1996-0938
1996
Hemley, R.J.McMillan, P.F., Hemley, R.J., Gillet, P.Vibrational spectroscopy of mantle mineralsIn: Mineral spectroscopy edited by Dyar, pp. 175-214.MantleMineral spectroscopy
DS1998-0511
1998
Hemley, R.J.Gillet, P., Hemley, R.J., McMillan, P.F.Vibrational properties at high pressures and temperaturesReviews in Mineralogy, Vol. 37, pp. 525-90.MantleMineralogy, Petrology - experimental
DS1998-0608
1998
Hemley, R.J.Hemley, R.J., Mao, H.K., Cohen, R.E.high pressure electronic and magnetic propertiesReviews in Mineralogy, Vol. 37, pp. 591-638.MantleMineralogy, Petrology - experimental
DS1998-0609
1998
Hemley, R.J.Hemley, R.J., Mao., H.K.X rays on deep mantle and core dynamicsIma 17th. Abstract Vol., p. A 36, abstractMantleGeodynamics
DS1998-0936
1998
Hemley, R.J.Mao, H-K., Hemley, R.J.New windows on the Earth's deep interiorReviews in Mineralogy, Vol. 37, pp. 1-32.GlobalLithosphere, Geophysics - gravity
DS1998-1415
1998
Hemley, R.J.Stixrude, L., Cohen, R.E., Hemley, R.J.Theory of minerals at high pressureReviews in Mineralogy, Vol. 37, pp. 639-MantleMineralogy, Petrology - experimental
DS2000-0460
2000
Hemley, R.J.Kagi, H., Lu, R., Hemley, R.J.Evidence for ice VI as an inclusion in cuboid diamonds from high pressure -temperature near infrared spectroscopy.Mineralogical Magazine, Vol. 64, No. 6, Dec. 1, pp. 1089-98.GlobalDiamond - inclusions, Diamond - morphology
DS2001-0468
2001
Hemley, R.J.Hemley, R.J., Mao, H.K.In situ studies of iron under pressure: new windows on the Earth's coreInternational Geology Review, Vol. 43, No. 1, Jan. pp. 1-30.MantleCore - mineralogy
DS2002-0704
2002
Hemley, R.J.Hemley, R.J., Mao, H.K.New windows on earth and planetary interiorsMineralogical magazine, Vol. 66,5, pp. 791-811.GlobalPetrology - mineralogy - not specific to diamonds
DS2002-0705
2002
Hemley, R.J.Hemley, R.J., Mao, H.K.New windows on earth and planetary interiorsMineralogical Magazine, Vol.66, 6, pp. 791-812.MantleCore
DS2003-0819
2003
Hemley, R.J.Lin, J.F., Heinz, D.L., Mao, H., Hemley, R.J., Devine, J.M., Shen, G.Stability of magnesiowurstite in Earth's lower mantleProceedings of the National Academy of Sciences, USA, Vol. 100, 8, pp. 4405-8.MantlePetrology
DS200412-1138
2003
Hemley, R.J.Lin, J.F., Heinz, D.L., Mao, H., Hemley, R.J., Devine, J.M., Shen, G.Stability of magnesiowurstite in Earth's lower mantle.Proceedings of National Academy of Science USA, Vol. 100, 8, pp. 4405-8.MantlePetrology
DS200512-0421
2005
Hemley, R.J.Hemley, R.J.,Chun Chen, Y., Yan, C-S.Growing diamond crystals by chemical vapor deposition.Elements, Vol. 1, 2, March pp. 105-108.CVD, HP
DS200512-0638
2005
Hemley, R.J.Lin, J.F., Struzhkin, V.V., Jacobsen, S.D., Hu, M.Y., Chow, P., Kung, J., Liu, H., Mao, H., Hemley, R.J.Spin transition of iron in magnesiowustite in the Earth's lower mantle.Nature, No. 7049, July 21, pp. 377-380.MantleMineralogy
DS200612-0338
2006
Hemley, R.J.Dobrzhinetskaya, L.F., liu, Z., Cartigny, P., Zhang, J., Tchkhetia, D., Hemley, R.J., Green II, H.W.Synchrotron infrared and Raman spectroscopy of microdiamonds from Erzgebirge, Germany.Earth and Planetary Science Letters, Vol. 248, 1-2, Aug. 15, pp. 325-334.Europe, GermanyMicrodiamonds
DS200612-0863
2006
Hemley, R.J.Mao, W.L., Mao, H-K., Sturhahn, W., Zhao, J., Prakapenka, V.B., Meng, Y., Shu, J., Hemley, R.J.Iron rich post perovskite and the origin of ultralow-velocity zones.Science, Vol. 312, April 28, pp. 564-565.MantleGeophysics - seismics, silicate
DS201312-0373
2012
Hemley, R.J.Hazen, R.M., Hemley, R.J., Mangolin, A.J.Carbon in Earth's Interior: storage, cycling and life.EOS Transaction of AGU, Vol. 93, 2, Jan 10, 3p.MantleReservoir - diamond mentioned
DS201701-0015
2016
Hemming, G.Hulett, S.R.W., Simonetti, A., Rasbury, E.T., Hemming, G.Recycling of subducted crustal components into carbonatite melts revealed by boron isotopes.Nature Geoscience, Vol. 9, pp. 904-908.MantleMagmatism

Abstract: The global boron geochemical cycle is closely linked to recycling of geologic material via subduction processes that have occurred over billions of years of Earth’s history. The origin of carbonatites, unique melts derived from carbon-rich and carbonate-rich regions of the upper mantle, has been linked to a variety of mantle-related processes, including subduction and plume-lithosphere interaction. Here we present boron isotope (?11B) compositions for carbonatites from locations worldwide that span a wide range of emplacement ages (between ~40 and ~2,600?Ma). Hence, they provide insight into the temporal evolution of their mantle sources for ~2.6 billion years of Earth’s history. Boron isotope values are highly variable and range between ?8.6‰ and +5.5‰, with all of the young (<300?Ma) carbonatites characterized by more positive ?11B values (>?4.0‰), whereas most of the older carbonatite samples record lower B isotope values. Given the ?11B value for asthenospheric mantle of ?7 ± 1‰, the B isotope compositions for young carbonatites require the involvement of an enriched (crustal) component. Recycled crustal components may be sampled by carbonatite melts associated with mantle plume activity coincident with major tectonic events, and linked to past episodes of significant subduction associated with supercontinent formation.
DS201612-2303
2016
Hemming, N.G.Hulett, S.R.W., Simonetti, A., Rasbury, E.T., Hemming, N.G.Recyclying of subducted crustal components into carbonatite melts revealed by boron isotopes.Nature Geoscience, Nov. 7, on line 6p.GlobalCarbonatite

Abstract: The global boron geochemical cycle is closely linked to recycling of geologic material via subduction processes that have occurred over billions of years of Earth’s history. The origin of carbonatites, unique melts derived from carbon-rich and carbonate-rich regions of the upper mantle, has been linked to a variety of mantle-related processes, including subduction and plume-lithosphere interaction. Here we present boron isotope (?11B) compositions for carbonatites from locations worldwide that span a wide range of emplacement ages (between ~40 and ~2,600?Ma). Hence, they provide insight into the temporal evolution of their mantle sources for ~2.6 billion years of Earth’s history. Boron isotope values are highly variable and range between ?8.6 and +5.5, with all of the young (<300?Ma) carbonatites characterized by more positive ?11B values (>?4.0‰ whereas most of the older carbonatite samples record lower B isotope values. Given the ?11B value for asthenospheric mantle of ?7 ± 1‰ the B isotope compositions for young carbonatites require the involvement of an enriched (crustal) component. Recycled crustal components may be sampled by carbonatite melts associated with mantle plume activity coincident with major tectonic events, and linked to past episodes of significant subduction associated with supercontinent formation.
DS200612-0889
2006
Hemming, S.R.McClennan, S.M., Taylor, S.R., Hemming, S.R.Composition, differentiation, and evolution of continental crust: constraints from sedimentary rocks and heat flow.Evolution and differentiation of Continental Crust, ed. Brown, M., Rushmer, T., Cambridge Univ. Press, Chapter 2, pp. 92-134.MantleMineral chemistry
DS200612-0896
2006
Hemming, S.R.McLennan, S.M., Taylor, S.R., Hemming, S.R.Composition, differentiation and evolution of continental crust: constraints from sedimentary rocks and heat flow.Brown, M., Rushmer, T., Evolution and differentiation of the continental crust, Cambridge Publ., Chapter 4,MantleGeothermometry
DS1960-1128
1969
Hemmings, C.D.Hemmings, C.D.Upper Mantle Structure in Western CanadaPh.d. Thesis, University of Alberta, 93p. Geological Society of Canada (GSC) TN269 H34Cordillera, Alberta, British ColumbiaMantle, Tectonics, Structure
DS2000-0853
2000
HemmingwaySandeman, H., Cousens, B., Peterson, Hemmingway, davisPetrochemistry and neodymium isotopic evolution of Proterozoic mafic rocks of Western Churchill Province... mantleGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) 2000, 4p. abstract.Northwest TerritoriesPetrology, dykes, Kaminak, MacQuid, Tulemalu
DS2003-1211
2003
Hemmingway, C.J.Sandeman, H.A., Cousens, B.L., Hemmingway, C.J.Continental tholeitic mafic rocks of the Paleoproterozoic Hurwitz Group, centralCanadian Journal of Earth Sciences, Vol. 40, 9,Sept. 1219-37.NunavutMagmatism
DS200412-1726
2003
Hemmingway, C.J.Sandeman, H.A., Cousens, B.L., Hemmingway, C.J.Continental tholeitic mafic rocks of the Paleoproterozoic Hurwitz Group, central Hearne sub-domain, Nunavut: insight into the evCanadian Journal of Earth Sciences, Vol. 40, 9,Sept. 1219-37.Canada, NunavutMagmatism
DS2001-0129
2001
Hemond, C.Bourdon, E., Hemond, C.Looking for the missing endmember in South Atlantic Ocean mantle around Ascension Island.Mineralogy and Petrology., Vol. 71, No. 1-2, pp. 127-38.MantleGondwana
DS201412-0310
2014
Hemond, C.Graham, D.W., Hanan, B.B., Hemond, C., Blichert-Toft, J., Albarede, F.Helium isotopic textures in Earth's upper mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, no. 5, pp. 2048-2074.MantleHelium
DS201608-1419
2016
Hemond, C.Maia, M., Sichel, S., Briais, A., Brunelli, D., Ligi, M., Ferreira, N., Campos, T., Mougel, B., Brehme, I., Hemond, C., Motoki, A., Moura, D., Scalabrin, C., Pessanha, I., Alves, E., Ayres, A., Oliveira, P.Extreme mantle uplift and exhumation along a transpressive transform fault.Nature Geoscience, Vol. 9, 8, pp. 619-623.MantleRidges

Abstract: Mantle exhumation at slow-spreading ridges is favoured by extensional tectonics through low-angle detachment faults1, 2, 3, 4, and, along transforms, by transtension due to changes in ridge/transform geometry5, 6. Less common, exhumation by compressive stresses has been proposed for the large-offset transforms of the equatorial Atlantic7, 8. Here we show, using high-resolution bathymetry, seismic and gravity data, that the northern transform fault of the St Paul system has been controlled by compressive deformation since ~10?million years ago. The long-lived transpression resulted from ridge overlap due to the propagation of the northern Mid-Atlantic Ridge segment into the transform domain, which induced the migration and segmentation of the transform fault creating restraining stepovers. An anticlockwise change in plate motion at ~11?million years ago5 initially favoured extension in the left-stepping transform, triggering the formation of a transverse ridge, later uplifted through transpression, forming the St Peter and St Paul islets. Enhanced melt supply at the ridge axis due to the nearby Sierra Leone thermo chemical anomaly9 is responsible for the robust response of the northern Mid-Atlantic Ridge segment to the kinematic change. The long-lived process at the origin of the compressive stresses is directly linked to the nature of the underlying mantle and not to a change in the far-field stress regime.
DS201704-0632
2017
Hemond, C.Kendrick, M.A., Hemond, C., Kamenetsky, V.S., Danyushevsky, L., Devey, C.W.Seawater cycled throughout Earth's mantle in partially serpentinized lithosphere.Nature Geoscience, Vol. 10, 3, pp. 222-228.MantleGeochemistry - water

Abstract: The extent to which water and halogens in Earth’s mantle have primordial origins, or are dominated by seawater-derived components introduced by subduction is debated. About 90% of non-radiogenic xenon in the Earth’s mantle has a subducted atmospheric origin, but the degree to which atmospheric gases and other seawater components are coupled during subduction is unclear. Here we present the concentrations of water and halogens in samples of magmatic glasses collected from mid-ocean ridges and ocean islands globally. We show that water and halogen enrichment is unexpectedly associated with trace element signatures characteristic of dehydrated oceanic crust, and that the most incompatible halogens have relatively uniform abundance ratios that are different from primitive mantle values. Taken together, these results imply that Earth’s mantle is highly processed and that most of its water and halogens were introduced by the subduction of serpentinized lithospheric mantle associated with dehydrated oceanic crust.
DS200512-0751
2004
hemphillMoses, T.M., Johnson, M.L., Green, B., Blodgett, Cino, Geurts, Gilbertson, hemphill, King, Kornylak, ReinitzA foundation for grading the overall cut quality of round brilliant cut diamonds.Gems & Gemology, Vol. 40, 3, Fall, pp. 202-228.Diamond cutting
DS2001-0970
2001
Hemphill, Gilbertson et. al.Reinitz, I.M., Johnson, Hemphill, Gilbertson et. al.Modeling the appearance of the round brilliant cut diamond: an analysis of fire and more about brilliance.Gems and Gemology, Vol. 37, Fall, pp. 174-97.GlobalDiamond - cutting, Brilliance
DS1998-0610
1998
Hemphill, T.S.Hemphill, T.S., Reinitz, I.M., Johnson, M.L., ShigleyModeling the appearance of the round brilliant cut diamond: an analysis ofbrilliance.Gems and Gemology, Fall pp. 158-183.GlobalDiamond cutting
DS1984-0746
1984
Hemphill, W.R.Tyson, R., Theisen, A.F., Granata, J.S., Hemphill, W.R.Detection of Visible Luminescence from a Rare Earth Elements (ree) Bearing Carbonatite in Southern California.Geological Society of America (GSA), Vol. 16, No. 4, P. 258. (abstract.)California, West CoastRelated Rocks
DS1986-0297
1986
Hempton, M.R.Gordon, M.B., Hempton, M.R.Collision induced rifting: the Grenville orogeny and The keweenawan rift of North AmericaTectonophysics, Vol. 127, No. 1-2, July 1, pp. 1-26MidcontinentTectonics
DS1999-0019
1999
HemstockArden, K.M., DePaoli, Johnson, Hemstock, AbercrombieMetallic and industrial mineral assessment report on the Athabasca permitsin northeastern Alberta.Alberta Geological Survey, MIN 19990004AlbertaExploration - assessment, Birch Mountain Resources Ltd.
DS1970-0529
1972
Henage, L.F.Henage, L.F.A Definitive Study of the Origin of LamproitesMsc. Thesis University of Oregon., United States, AustraliaLamproite, Review
DS1997-1223
1997
Hendel, R.Walzer, U., Hendel, R.Tectonic episodicity and convective feed back mechanismPhysics of the Earth and Planetary Interiors, Vol. 100, No. 1-3, pp.MantleTectonics, Plumes
DS200412-2077
2004
Hendel, R.Walzer, U., Hendel, R., Baumgardner, J.The effects of a variation of the radial viscosity profile on mantle evolution.Tectonophysics, Vol. 384, 1-4, pp. 55-90.MantleGeophysics - seismics
DS200812-1230
2008
Hendel, R.Waltzer, U., Hendel, R.Mantle convection and evolution with growing continents.Journal of Geophysical Research, Vol. 113, B09405.MantleConvection
DS200812-1231
2008
Hendel, R.Walzer, U., Hendel, R.Mantle convection and evolution with growing continents.Journal of Geophysical Research, Vol. 113, B9, B09405.MantleConvection
DS200612-0483
2006
Hendel, R.F.Gottschaldt, K.D., Walzer, U., Hendel, R.F., Stegman, D.R., Baumgartner, J.R., Muhlhaus, H.B.Stirring in 3 d spherical models of convection in the Earth's mantle.Philosophical Magazine, Vol. 86, no. 21-22, pp. 3175-3204.MantleConvection
DS1996-1541
1996
HendersonWilkinson, L., Budkewitsch, P., Graham, D.F., HendersonAlternative methods of base map generation using remote sensing and GIS: a pilot study western Churchill ProvinceGeological Survey of Canada Current Research, No. 1997-C, pp. 81-90.Northwest TerritoriesRemote sensing, GIS
DS202011-2041
2013
Henderson, B.Henderson, B., Collins, A.S., Payne, J., Forbes, C., Saha, D.Geological and geochemistry constraining India in Columbia: the age, isotopic provenance and geochemistry of the protoliths of the Ongole Domain, southern eastern Ghats, India. *** NOTE DATEGondwana Research, in press available. 19p. PdfIndiaNuna

Abstract: The Ongole Domain in the southern Eastern Ghats Belt of India formed during the final stages of Columbia amalgamation at ca. 1600 Ma. Yet very little is known about the protolith ages, tectonic evolution or geographic affinity of the region. We present new detrital and igneous U-Pb-Hf zircon data and in-situ monazite data to further understand the tectonic evolution of this Columbia-forming orogen. Detrital zircon patterns from the metasedimentary rocks are dominated by major populations of Palaeoproterozoic grains (ca. 2460, 2320, 2260, 2200-2100, 2080-2010, 1980-1920, 1850 and 1750 Ma), and minor Archaean grains (ca. 2850, 2740, 2600 and 2550 Ma). Combined U-Pb ages and Lu-Hf zircon isotopic data suggest that the sedimentary protoliths were not sourced from the adjacent Dharwar Craton. Instead they were likely derived from East Antarctica, possibly the same source as parts of Proterozoic Australia. Magmatism occurred episodically between 1.64 and 1.57 Ga in the Ongole Domain, forming felsic orthopyroxene-bearing granitoids. Isotopically, the granitoids are evolved, producing ?Hf values between ? 2 and ? 12. The magmatism is interpreted to have been derived from the reworking of Archaean crust with only a minor juvenile input. Metamorphism between 1.68 and 1.60 Ga resulted in the partial to complete resetting of detrital zircon grains, as well as the growth of new metamorphic zircon at 1.67 and 1.63 Ga. In-situ monazite geochronology indicates metamorphism occurred between 1.68 and 1.59 Ga. The Ongole Domain is interpreted to represent part of an exotic terrane, which was transferred to proto-India in the late Palaeoproterozoic as part of a linear accretionary orogenic belt that may also have included south-west Baltica and south-eastern Laurentia. Given the isotopic, geological and geochemical similarities, the proposed exotic terrane is interpreted to be an extension of the Napier Complex, Antarctica, and may also have been connected to Proterozoic Australia (North Australian Craton and Gawler Craton).
DS1986-0247
1986
Henderson, C.M.B.Foland, K.A., Henderson, C.M.B.Crustal contamination during genesis of the Mont. St. Hilairealkaline igneous complex, QuebecEos, Vol. 67, No. 16, April 22, p. 389. (abstract.)QuebecNepheline syenite, Alkaline rocks
DS1989-0435
1989
Henderson, C.M.B.Foland, K.A., Chen, J.-F, Linder, J.S., Henderson, C.M.B., WhillansHigh resolution 40Ar/39Ar chronology of multiple intrusion igneouscomplexes, . Application to the Cretaceous Mount Brome complex, Quebec, CanadaContributions to Mineralogy and Petrology, Vol. 102, No. 2, pp. 127-137QuebecMount Brome, Igneous complex
DS1989-0621
1989
Henderson, C.M.B.Henderson, C.M.B., Ezepue, M.J.Petrogenesis of the dyke suite from the Marangudzialkaline igneous ringcomplex, ZimbabweGeological Society of India, Memoir, Editor C. LeelanandaM., No. 15, pp. 83-116ZimbabweAlkaline rocks, Basanite-pseudoleucite ri
DS1991-0898
1991
Henderson, C.M.B.Kogarko, L.N., Plant, D.A., Henderson, C.M.B., Kjarsgaard, B.A.Sodium rich carbonate inclusions in perovskite and calzirtite from the Guli intrusive Ca-carbonatite, Polar SiberiaContributions to Mineralogy and Petrology, Vol. 109, No. 1, pp. 124-129Russia, SiberiaCarbonatite, Carbonate inclusions
DS1991-0899
1991
Henderson, C.M.B.Kohn, S.C., Dupree, R., Mortuza, M.G., Henderson, C.M.B.An NMR study of structure and ordering in synthetic K2gSi5O12, a leuciteanaloguePhys. Chem. Minerals, Vol. 18, pp. 144-152GlobalMineral chemistry, Leucite
DS1994-0291
1994
Henderson, C.M.B.Chen, J., Henderson, C.M.B., Foland, K.A.Open system, subvolcanic magmatic evolution: constraints on the petrogenesis Mount Brome alkaline C.Journal of Petrology, Vol. 35, No. 4, pp. 1127-1153.QuebecAlkaline complex, Deposit -Mount Brome
DS1994-0529
1994
Henderson, C.M.B.Foland, K.A., Landoll, .J.D., Henderson, C.M.B.Some consequences of interaction between mantle magmas and crust in the formation of epizonal alkaline complexes.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p.MantleAlkaline rocks
DS1994-0976
1994
Henderson, C.M.B.Landoll, J.D., Foland, K.A., Chen, J-F., Henderson, C.M.B.The role of crustal contamination in the formation of silica oversaturated rocks in the Montregian Hills province, Quebec.Geological Association of Canada (GAC) Abstract Volume, Vol. 19, p. posterQuebecAlkaline rocks, Montregian Hills
DS1995-0986
1995
Henderson, C.M.B.Kogarko, L.N., Pacheco, H., Henderson, C.M.B.Primary Calcium rich carbonatite magma, carbonate -silicate -sulphide liquid immiscibility in the upper mantle.Contributions to Mineralogy and Petrology, Vol. 121, No. 3, pp. 267-274.GlobalCarbonatite
DS1995-0989
1995
Henderson, C.M.B.Kohn, S.C., Henderson, C.M.B., Dupree, R.Si-Al order in leucite revisited: new information from an analcite derivedanalogue.American Mineralogist, Vol. 80, July-Aug. No. 7-8, pp. 705-714.GlobalMineralogy, Leucite
DS1996-0521
1996
Henderson, C.M.B.Gibb, F.G.F., Henderson, C.M.B.Magmatic processes - introductionMineralogical Magazine, Vol. 60, No. 1, Feb pp. 1-4GlobalMagmatic processes
DS1996-0622
1996
Henderson, C.M.B.Henderson, C.M.B., Foland, K.A.Barium and Titanium rich primary biotite from the Brome alkaline igneous complex, Montregian Hills: substitution ...Canadian Mineralogist, Vol. 34, pt. 6, pp. 1241-52.QuebecSpectroscopy, Mechanisms -substitution
DS1999-0304
1999
Henderson, C.M.B.Henderson, C.M.B., Kogarko, L.N., Plant, D.A.Extreme closed system fractionation of volatile rich ultrabasic peralkaline melt inclusions .. djerfisheriteMineralogical Magazine, Vol. 63, No. 3, June, pp. 433-GlobalKugda alkaline complex
DS201212-0293
2012
Henderson, C.M.B.Henderson, C.M.B., Richardson, F.R., Charnock, J.M.The Highwood Mountains potassic igneous province, Montana: mineral fractionation trends and magmatic processes revisited.Mineralogical Magazine, Vol. 76, 4, pp. 1005-1051.United States, MontanaHighwood Mountains
DS1989-0622
1989
Henderson, C.M.R.Henderson, C.M.R., Pendlebury, K., Foland, K.A.Mineralogy and petrology of the Red Hill alkaline igneous complex, NewHampshire, United States (US)Journal of Petrology, Vol. 30, No. 3, June pp. 627-666GlobalAlkaline rocks, Red Hill complex
DS2001-0469
2001
Henderson, D.M.Henderson, D.M.New visualization of global tectonic plate motions and plate boundary interactionsTerra Nova, Vol. 13, pp. 70-8.MantleTectonics, Plate - boundary
DS1930-0305
1939
Henderson, E.P.Ksanda, C.J., Henderson, E.P.Identification of Diamond in the Canon Diablo IronAmerican MINERALOGIST., Vol. 24, PP. 677-680.United States, Arizona, Colorado PlateauMeteorite
DS201412-0353
2014
Henderson, G.A.Henderson, G.A., Neuville, D.R.Spectroscopic methods in mineralogy and materials sciences. Mineralogical Society of America, Vol. 78, 763p. $ 50.00TechnologyBook - spectroscopy
DS202106-0972
2021
Henderson, G.M.Sun, J., Zhu, X-K., Belshaw, N.S., Chen, W., Doroshkevich, A.G., Luo, W.J., Song, W.L., Chen, B.B., Cheng, Z.G., Li, Z.H., Wang, Y., Kynicky, J., Henderson, G.M.Ca isotope systematics of carbonatites: insights into carbonatite source and evolution.Geochemical Perspectives Letters, Vol. 17, pp. 11-15. pdfMantlecarbonatites

Abstract: Carbonatite, an unusual carbonate-rich igneous rock, is known to be sourced from the mantle which provides insights into mantle-to-crust carbon transfer. To constrain further the Ca isotopic composition of carbonatites, investigate the behaviour of Ca isotopes during their evolution, and constrain whether recycled carbonates are involved in their source regions, we report ?44/42Ca for 47 worldwide carbonatite and associated silicate rocks using a refined analytical protocol. Our results show that primary carbonatite and associated silicate rocks are rather homogeneous in Ca isotope compositions that are comparable to ?44/42Ca values of basalts, while non-primary carbonatites show detectable ?44/42Ca variations that are correlated to ?13C values. Our finding suggests that Ca isotopes fractionate during late stages of carbonatite evolution, making it a useful tool in the study of carbonatite evolution. The finding also implies that carbonatite is sourced from a mantle source without requiring the involvement of recycled carbonates.
DS200612-0566
2005
Henderson, G.S.Henderson, G.S.The structure of silicate melts: a glass perspective.The Canadian Mineralogist, Vol. 43, 6, Dec. pp. 1921-1958.TechnologySilicate melts
DS200712-0428
2006
Henderson, G.S.Henderson, G.S., Calas, G., Stebbins, J.F.The structure of silicate glasses and melts.Elements, Vol. 2, 5, October pp. 269-274.TechnologyGeochemistry
DS201112-0863
2010
Henderson, G.S.Richet, P., Henderson, G.S., Neuville, D.R.Thermodynamics: the oldest branch of earth sciences?Elements, Vol. 6, pp. 287-292.MantleGeothermometry
DS201712-2710
2017
Henderson, G.S.Nesbitt, H.W., Cormack, A.N., Henderson, G.S.Defect contributions to the heat capacities and stabilities of some chain, ring, and sheet silicates, with implications for mantle minerals.American Mineralogist, Vol. 102, pp. 2220-2229.Mantlemineralogy

Abstract: At temperatures less than ~1500 K, previously published CP data demonstrate that the heat capacities of orthoenstatite, proto-enstatite, diopside, and pseudowollastonite include primarily Debye type vibrational and anharmonic contributions, whereas the alkali chain, sheet, and ring silicates, Na2SiO3, Li2SiO3, K2SiO3, and Na2Si2O5 include a third contribution. The third contribution to CP arises from defect formation due to the mobility Na, K, Li, and O2-. The contribution becomes apparent at temperatures above 700-800 K for Na and K silicates, and above 900-1000 K for Li metasilicate. With strong thermal agitation, alkali-non-bridging oxygen (NBO) bonds are ruptured with the cations exiting their structural sites to occupy interstitial sites, thereby producing intrinsic Frenkel defects, which contribute to the CP of the alkali silicates. The magnitudes of the CP defect contributions correlate inversely with cation-oxygen bond strengths, as measured by bond dissociation energies. K-O and Na-O bond strengths are weak (239 and 257 kJ/mol) and defect contributions are large for these alkali chain, ring, and sheet silicates. The greater bond strength of Li-O (341 kJ/mol) correlates with a weaker defect contribution to the CP of Li2SiO3. Mg-O and Ca-O bonds are stronger still (394 and 464 kJ/mol) and no CP defect contributions are observed for the pyroxenes and pseudowollastonite up to ~1500 K. Above ~800 K a polymerization reaction occurs in Na2SiO3, which produces some Q3 species and free oxygen (O2- or oxide ion). The polymerization reaction annihilates an oxygen structural site so that the O2- produced must reside on non-structural sites thus producing intrinsic anionic defects. The same reactions likely occur in Na2Si2O5 and K2SiO3. Raman spectra of Na2SiO3 indicate >10% of Na+ and ~1.7% of O2- on interstitial sites at 1348 K. Ca- and Mg-bearing mantle minerals subjected to temperature greater than ~1500 K experience the destabilizing effects of disordering (Frenkel defect formation). The minerals may respond either by changing their composition or by changing phase. An abundance of Ca and Na defects in pyroxenes, for example, likely promotes production of new components (e.g., CaAl2SiO6, NaAlSi2O6) in pyroxenes. By their production, Ca and Na defect concentrations are reduced thereby stabilizing the phases. Mg-O bond dissociation and production of intrinsic Mg2+ and O2- point defects within olivine likely destabilize it and promote the phase transition to wadsleyite at the base of the upper mantle.
DS1930-0064
1931
Henderson, H.Henderson, H.Diamonds and de BeersChamber's Journal, Vol. 7, AUGUST, No. 21, PP. 504-506.South AfricaMining Economics
DS200612-1358
2006
Henderson, I.St.Onge, M.R., Jackson, G.D., Henderson, I.Geology, Baffin Island south of 70 N and east of 80 W.Geological Survey of Canada, No. 4931, 1 CD $ 9.10Canada, NunavutBedrock data
DS200812-1213
2008
Henderson, I.H.C.Viola, G., Henderson, I.H.C., Bingen, B., Thomas, R.J., Smethurst, M.A., De Azavedo, S.Growth and collapse of a deeply eroded orogen: insights from structural, geophysical, and geochronological constraints on Pan-African evolution of NE Mozambique.Tectonics, Vol. 27, TC5009Africa, MozambiqueGeochronology
DS1970-0559
1972
Henderson, J.Mcglynn, J., Henderson, J.The Slave ProvinceGeological Association of Canada (GAC) Special paper, No. 11, pp. 506-26.Northwest TerritoriesGeology - Overview
DS201812-2862
2018
Henderson, J.Peters, M.H., Henderson, J.Bridging the gap through care and collaboration: before closure and after production. Snap Lake2018 Yellowknife Geoscience Forum , pp. 60-61. abstractCanada, Northwest territoriesdeposit - Snap Lake

Abstract: Wikipedia defines “Care and Maintenance” as a term used in the mining industry to describe processes and conditions on a closed mine site where there is potential to recommence operations at a later date. During a care and maintenance phase, production is stopped but the site is managed to ensure it remains in a safe and stable condition. De Beers Canada Inc. - Snap Lake Mine entered the Care and Maintenance phase after production ceased in December 2015. The partnership with Det'on Cho Corporation provides for a sustainable execution of care and maintenance activities, taking into consideration approved work plans, mine health and safety considerations and emergency response plans. The mine is currently in its third year of care and maintenance. After exploring the potential sale of the asset and assessing the possibility of reopening the mine, the decision to proceed toward closure was taken in December 2017, ushering Snap Lake into a period of extended care and maintenance (ECM) while a closure plan is developed and finalized. Activities during ECM include monitoring of water quality and other environmental parameters, collecting/treating effluent and making sure that water leaving the site meets water license compliance. Physical infrastructure such as the airstrip, roads, buildings, processed kimberlite containment facilities and associated surface water infrastructure such as sumps, pumps and channels need to be kept in a safe and operable condition. Camp infrastructure such as generators and machinery and equipment are also part of the Care and Maintenance program. Collaboration between the De Beers Canada owner's team and Det'on Cho Corporation resulted in the safe execution of the 2018 work plan which included freshet operations, continued progressive reclamation work, monitoring and maintenance activities. After a trial-run of reduced camp occupancy in the winter of 2017, the site was fully winterized and demobilized in September 2018 to allow for monthly site visits for the duration of the winter and planning for a spring 2019 start-up.
DS1860-0990
1897
Henderson, J.A.Henderson, J.A.On a New Occurrence of Apophyllite in South AfricaMineralogical Magazine., Vol. 11, DECEMBER PP. 318-322. ALSO: Neues Jahrbuch f?r Mineralogie BD. 1Africa, South AfricaCrystallography, Mineralogy
DS1900-0761
1909
Henderson, J.M.Henderson, J.M.Discussion on Paper by Harger "the Occurrence of Diamonds In the Dwyka Congomerate".Geological Society of South Africa Proceedings, Vol. 12, P. XLIX.Africa, South AfricaDiamond Genesis
DS1900-0762
1909
Henderson, J.M.Henderson, J.M.Discussion on Paper by Merensky " the Diamond Deposits of Luderitzland".Geological Society of South Africa Proceedings, Vol. 12, P. XXXIX.Africa, NamibiaMarine Diamond Placers
DS1910-0191
1911
Henderson, J.M.Henderson, J.M.Anniversary Address by the PresidentGeological Society of South Africa Proceedings, Vol. 13, PP. XXI-XXXIV.South AfricaGenesis
DS1960-0359
1963
Henderson, J.R.Keller, F.JR., Henderson, J.R., et al.Aeromagnetic Map of the Magnet Cove Area, Hot Spring County, Arkansaw.United States Geological Survey (USGS) MAP, No. GP 409, 1: 24, 000.United States, Gulf Coast, Arkansas, Hot Spring CountyGeophysics
DS1990-0684
1990
Henderson, J.R.Henderson, J.R., Broome, J.Geometry and kinematics of Wager shear zone interpreted from structural fabrics and magnetic data.Canadian Journal of Earth Sciences, Vol. 27, pp. 590-604.GlobalTectonics, Geophysics - magnetics
DS1997-0501
1997
Henderson, J.R.Henderson, J.R., henderson, M.N., Kerswill, J.A., DehlsGeology of High Lake greenstone belt, District of MackenzieGeological Society of Canada (GSC) Open File, OF. 3401, approx. $ 20.00Northwest TerritoriesBook - ad, Greenstone belt
DS1997-1211
1997
Henderson, J.R.Villeneuve, M.E., Henderson, J.R., Hrabi, R.B., Jackson2.80-2.58 Ga plutonism and volcanism in the Slave ProvinceGeological Survey of Canada (GSC) Paper, No. 1997-F, pp. 37-60.Northwest TerritoriesGeochronology, Craton - Slave
DS1997-1212
1997
Henderson, J.R.Villeneuve, M.E., Henderson, J.R., Hrabi, R.B., Jackson2.70 - 2.58 Ga plutonism and volcanism in the Slave Province, District ofMackenzie, Northwest Territories.Geological Society of Canada (GSC) Paper, No. 1997-F, p. 37-60.Northwest TerritoriesGeochronology, Magma activity
DS1995-0983
1995
Henderson, M.Kogarko, L.N., Henderson, M., Pacheco, A.H.Primary Ca-rich carbonatite magma and carbonate silicate sulphide liquidimmiscibility in upper mantle.Geological Society Africa 10th. Conference Oct. Nairobi, p. 113-4. Abstract.GlobalCarbonatite, Deposit -Montana Clara
DS1997-0501
1997
henderson, M.N.Henderson, J.R., henderson, M.N., Kerswill, J.A., DehlsGeology of High Lake greenstone belt, District of MackenzieGeological Society of Canada (GSC) Open File, OF. 3401, approx. $ 20.00Northwest TerritoriesBook - ad, Greenstone belt
DS1986-0357
1986
Henderson, P.Henderson, P., Selo, M., Storzer, D.An investigation of olivine crystal growth in a picrite dike using the fission track methodMineralogical Magazine, Vol. 50, No. 1, No. 355, March pp. 27-33GlobalPicrite
DS1997-0155
1997
Henderson, P.Campbell, L.S., Henderson, P.Apatite paragenesis in the Bayan Obo rare earth elements (REE) niobium iron ore deposit, Inner China.Lithos, Vol. 42, No. 1-2, Dec. 1, pp. 89-104.China, MongoliaCarbonatite, Deposit - Bayan Obo
DS1999-0684
1999
Henderson, P.Smith, M.P., Henderson, P., Zhang, P.Reacyion relationships in the Bayan Obo rare earth elements (REE) niobium deposit, Inner Mongolia: implications for stability rare earth elements (REE)Contributions to Mineralogy and Petrology, Vol. 134, No. 2-3, pp. 294-310.China, MongoliaCarbonates, phosphates, rare earths, Deposit - Bayan Obo
DS200712-0133
2007
Henderson, P.Campbell, L.S., Wall, F., Henderson, P., Zhang, P., Tao, K., Yang, Z.The character and context of zircons from the Bayan Obo Fe Nb REE deposit, Inner Mongolia.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 97-98.Asia, MongoliaCarbonatite
DS200712-0134
2007
Henderson, P.Campbell, L.S., Wall, F., Henderson, P., Zhang, P., Tao, K., Yang, Z.The character and context of zircons from the Bayan Obo Fe Nb REE deposit, Inner Mongolia.Frontiers in Mineral Sciences 2007, Joint Meeting of Mineralogical societies Held June 26-28, Cambridge, Abstract Volume p. 97-98.Asia, MongoliaCarbonatite
DS1999-0685
1999
Henderson, P.H.Smith, M.P., Henderson, P.H.Fluid inclusion constraints on the genesis of the Bayan Obo iron rare earth elements (REE) niobium deposit .Stanley, SGA Fifth Biennial Symposium, pp. 103-6.ChinaCarbonatite, Geochronology
DS1996-0623
1996
Henderson, P.J.Henderson, P.J.Kimberlite indicator mineral dat a from Bissett-English -Brook-Wallace Lake area 62P, 1, 52L1, 52M3, 4 Rice Lake gsGeological Survey of Canada Open File, No. 3367, 23p. $ 9.00ManitobaGeochemistry, Kimberlite indicator minerals
DS2002-1034
2002
Henderson, P.J.McMartin, I., Henderson, P.J.Re-interpretation of the ice flow history within the Keewatin sector of the Laurentide ice sheet: results from the western Churchill Natmap project.30th. Yellowknife Geoscience Forum, Abstracts Of Talks And Posters, Nov. 20-22, p. 46. abstractNorthwest TerritoriesGeomorphology
DS2003-0918
2003
Henderson, P.J.McMartin, I., Henderson, P.J., Kjarsgaard, B.K., Venance, K.Regional distribution and chemistry of kimberlite indicator minerals, Rankin In let andGeological Survey of Canada Open File, No. 1575, 1 CD Rom 110p. report 60p. of appendices $40.NunavutMineral chemistry
DS201602-0211
2015
Henderson, R.Henderson, R.The first gravity meter designed, built and used in Australia in the late 1890's and very possibly the first in the world.Preview ( Geophysics), December pp. 53-61.AustraliaHistory - gravity meter
DS1940-0086
1944
Henderson, R.H.Henderson, R.H.An Ulsterman in AfricaCape Town: Union Volkspers Ltd., South AfricaHistory, Kimberley
DS1992-0698
1992
Henderson, W.A.Henderson, W.A.Hercynite crystals from the Kimzey calcite Quarry Magnet Cove, Arkansaw...and theri distinction from perovskiteRocks and Minerals, Vol. 67, No. 6, November-December pp. 402-404ArkansasPerovskite, Carbonatite
DS1997-0524
1997
Henderson-Sellers, A.Howe, W., Henderson-Sellers, A.Assessing climate changeGordon and Breach Publ, 430p. approx. $ 150.00GlobalBook - ad, Climate change
DS1984-0236
1984
Hendey, Q.Dingle, R.V., Hendey, Q.Late Mesozoic and Tertiary Sediment Supply to the Eastern Cape Basin southeast Atlantic and Palaeo-drainage Systems in South We Sout Africa.Marine Geology, Vol. 56, No. 1-4, PP. 13-26.South Africa, Orange River, Namaqualand, Southwest AfricaGeomorphology, Submarine Diamond Placers, Sedimentology
DS1992-0699
1992
Hendrick, K.C.Hendrick, K.C.The environmental challenge of growthMinerals Industry International, No. 1006, May pp. 17-21GlobalEconomics, Mineral industries -environmental issues
DS1992-0700
1992
Hendricks, C.Hendricks, C., Scoble, M.J., Boudreault, F., Szymanski, J.Blasthole stoping: drilling accuracy and measurementTransactions of the Institute of Mining and Metallurgy (IMM), Vol. 101, Sept-Dec, pp. A 173-186GlobalDrilling -blasthole stoping, Overview of advances
DS1994-0759
1994
Hendricks, C.Hendricks, C., Scobie, M., Boudreault, F.A study of blasthole drilling accuracy: monitoring instrumentation andpracticeThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 87, No. 977, February pp. 60-66ManitobaDrilling, Mining -dilution
DS1980-0174
1980
Hendricks, J.D.Hildenbrand, T.G., Kucks, R.P., Kane, M.F., Hendricks, J.D.Aeromagnetic Map and Associated Depth Map of the Upper Mississippi Embayment Region.United States Geological Survey (USGS) miscellaneous FIELD MAP, No. MF-1158, 1: 1, 000, 000.GlobalMid-continent
DS1981-0232
1981
Hendricks, J.D.Kane, M.F., Hildenbrand, T.G., Hendricks, J.D.A Model for the Tectonic Evolution of the Mississippi Embayment and its Contempory Seismicity.Geology, Vol. 9, No. 12, PP. 563-568.GlobalMid-continent
DS1982-0277
1982
Hendricks, J.D.Hildenbrand, T.G., Kane, M.F., Hendricks, J.D.Magnetic Basement in the Upper Mississippi Embayment Region-a Preliminary Report.United States Geological Survey (USGS) PROF. PAPER., No. 1236-E.GlobalMid-continent
DS1989-0623
1989
Hendricks, J.D.Hendricks, J.D.Map showing bouguer gravity and generalized geology of Arkansaw. Kimberlite mentioned p. 21United States Geological Survey (USGS) Prof. Paper, No. 1474, and map 1: 1, 1000, 000 $ 4.00ArkansasGeophysics -gravity, Geology map
DS1992-0379
1992
Hendricks, J.D.Donovan-Ealy, P.F., Hendricks, J.D.Gravity and magnetic anomalies associated with Tertiary volcanism and a Proterozoic crustal boundary, Hopi Buttes volcanic field, Navajo Nation, ArizonaGeological Society of America (GSA) Abstracts with programs, 1992 Annual, Vol. 24, No. 7, abstract p. A82ArizonaGeophysics -magnetics, volcanism.
DS1995-0798
1995
Hendricks, J.D.Hildenbrand, T.G., Hendricks, J.D.Geophysical setting of the Reelfoot Rift and relations between rift structures and the New Madrid seismic zoneUnited States Geological Survey (USGS) Paper, No. 1538-E, 30p. $ 3.50Arkansas, Missouri, Midcontinent, MississippiGeophysics -seismics, Tectonics, Mid continent Rift
DS1995-0799
1995
Hendricks, J.D.Hildenbrand, T.G., Hendricks, J.D.Geophysical setting of the Reelfoot Rift and relations bewteen rift structures and the New Madrid seismic zoneUnited States Geological Survey (USGS) Paper, No. 1538-E, 30p. $ 3.50Missouri, Arkansas, Tennessee, KentuckyTectonics, Mid continent rifting
DS201312-0199
2013
Hendriks, B.De Min, A., Hendriks, B., Siejko, F., Comin-Chiaramonti, P., Girardi, V., Ruberti, E., Gomes, C.B., Neder, R.D., Pinho, F.C.Age of ultramafic high K rocks from Planalto da Serra ( Mato Grosso, Brazil).Journal of South American Earth Sciences, Vol. 41, pp. 57-64.South America, BrazilGeochronology
DS201112-0280
2011
Hendriks, B.W.HDominguez, A.R., Van der Voo, R., Torsvik, T.H., Hendriks, B.W.H, Abrajevitch, A., Domeier, M., Larsen, B.T., Rousse, S.The ~270 Ma paleolatitude of Baltica and its significance for Pangea models.Geophysical Journal International, In press availableEurope, Baltic ShieldGeochronology
DS200512-0898
2005
Hendriks, B.W.H.Redfield, T.F., Osmundsen, P.T., Hendriks, B.W.H.The role of fault reactivation and growth in the uplift of western Fennoscandia.Journal of the Geological Society, Vol. 162, 6, pp. 1013-1030.Europe, FinlandTectonics
DS1993-0258
1993
Hendriks, M.Clark, J.A., Hendriks, M., Timmermans, T.J., Struck, C., Hilverda, K.J.Glacial isostatic deformation of the Great Lakes regionGeological Society of America Bulletin, Vol. 106, No. 1, January pp. 19-31.OntarioGeomorphology, Sea level changes, isostasy
DS2001-0470
2001
Hendrix, M.S.Hendrix, M.S., Davis, G.A.Paleozoic and Mesozoic tectonic evolution of central and eastern Asia: continental assembly /deformationGeological Society of America, Publication, MWR No. 194, 454p. $ 160.00AsiaBook - ad, Tectonics
DS2001-0471
2001
Hendrix, M.S.Hendrix, M.S., Davis, G.A.Paleozoic and Mesozoic tectonic evolution of central Asia: from continental assembly to intracontinental...Geological Society of America Memoir, No. 194, 440p.AsiaBook - table of contents
DS1990-1459
1990
HendryThompson, R.N., Leat, P.T., Dickin, A.P., Morrison, M.A., HendryStrongly potassic mafic magmas from lithospheric mantle sources duringEarth and Planetary Science Letters, Vol. 98, pp. 139-153ColoradoMinettes, Chemistry
DS1991-0572
1991
HendryGibson, S.A., Thompson, R.N., Leat, P.T., Morrison, M.A., HendryUltrapotassic magmas along the flanks of the oligo-miocene Rio Grande @Proceedings of Fifth International Kimberlite Conference held Araxa June, pp. 133-135Colorado PlateauTectonics, Kimberlites, minettes
DS1993-0541
1993
HendryGibson, S.A., Thompson, R.N., Leat, P.T., Morrison, M.A., HendryUltrapotassic magmas along the flanks of the Oligo-Miocene Rio GrandeJournal of Petrology, Vol. 34, No. 1, February pp. 187-228Mantle, Colorado PlateauUltrapotassic, Tectonics
DS1987-0492
1987
Hendry, G.L.Morrison, M.A., Hendry, G.L., Leat, P.T.Regional and tectonic implications of parallel Caledonian and Permo Carboniferous lamprophyre dyke swarms from Lismore, ArdgourTransactions Royal Society. Edinburgh, Vol. 77, pp. 279-288ScotlandDyke, Shoshonite
DS1988-0412
1988
Hendry, G.L.Leat, P.T., Thompson, R.N., Morrison, M.A., Hendry, G.L., DickinSilicic magmas derived by fractional crystallizationfromMioceneminette, Elkhead Mountains, ColoradoMineralogical Magazine, Vol. 52, No. 368, pt. 5, December pp. 577-586ColoradoMinette
DS1988-0413
1988
Hendry, G.L.Leat, P.T., Thompson, R.N., Morrison, M.A., Hendry, G.L., DickinCompositionally -diverse Miocene -Recent rift related magmatism inJournal of Petrology, Special Volume 1988- Oceanic and Continental, pp. 351-377ColoradoTectonics, Rift
DS1989-0864
1989
Hendry, G.L.Leat, P.T., Thompson, R.N., Morrison, M.A., Hendry, G.L., DickinIdentification of magma sources in continental maficmagmatism: the Rio Grande RiftNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 160. AbstractColorado PlateauTectonics
DS1991-0967
1991
Hendry, G.L.Leat, P.T., Thompson, R.N., Morrison, M.A., Hendry, G.L., DickinAlkaline hybrid mafic magmas of the Yampa area, northwest Colorado, and their relationship to the Yellowstone mantle plume and lithospheric mantle domainsContributions to Mineralogy and Petrology, Vol. 107, No. 3, pp. 310-327ColoradoAlkaline rocks, Mantle plumes
DS1900-0194
1903
Heneage, E.F.Heneage, E.F.The Phenomena of the Diamondiferous Deposits in South Africa #2Institute of Mining and Metallurgy. Transactions, Vol. 12, PP. 115-139. ALSO: MIN. Journal of, Vol. 72, P.Africa, South AfricaGeology
DS1900-0117
1902
Heneage, E.J.Heneage, E.J.Sopra I Depositi Diamantiferi Dell' Africa Meridionale. Riassunto Da Communicazione Di Heneage.Rass. Mineraria Torino, Vol. 17, PP. 292-295.Africa, South AfricaDiamonds, Geology
DS201112-0430
2011
Heneyi, G.Heneyi, G., Godard, V., Cattin, R., Connolly, J.A.D.Incorporating metamorphism in geodynamic models: the mass conservation problem.Geophysical Journal International, In press available,MantleTectonics
DS201809-2036
2018
Henger, F.E.Hoover, D.B., Karfunkel, J., Walde, D., Moraes, R.A.V., Michelfelder, G., Henger, F.E., Ribeira, L.C., Krambock, K.The Alto Paranaiba region, Brazil: a continuing source for pink diamonds?The Australian Gemmologist, Vol. 26, 9-10, pp. 196-204.South America, Brazildeposit - Alto Paranaiba
DS200512-0685
2003
Hengweng, Z.Marakushev, A.A., Lonkan, S., Bobrov, A.V., Hengweng, Z., Fu, L.Evolution of the SuLu eclogite ultramafic foldbelt in East China.Moscow University Geology Bulletin, Vol. 58, 6, pp. 33-46.ChinaUHP
DS1994-0760
1994
Henharen, P.Henharen, P., Stephenson, M.Russian vs western recovery plantsThe Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Section Meeting Oct. 12, Vancouver, List of speakersGlobalUpdate, Mineral processing
DS1994-0761
1994
Henharen, P.A.Henharen, P.A., Popplewell, G., Shirley, J.M., Stephenson, M.Diamond processing - design considerations for the Northwest TerritoriesBateman Preprint paper handout at The Canadian Institute of Mining, 40p.Northwest TerritoriesDiamond recovery, Mineral processing
DS1992-0701
1992
Henheron, P.Henheron, P.Diamond processingInternational Roundtable Conference on Diamond Exploration and Mining, held, pp. 150-173GlobalMining, Mineral processing
DS2003-0641
2003
Henin, O.Jahn, B., Fan, Q., Yang, J.J., Henin, O.Petrogenesis of the Maowu pyroxenite eclogite body from the UHP metamorphicLithos, Vol. 70, 3-4, pp. 243-67.ChinaUHP, geochronology
DS200412-0898
2003
Henin, O.Jahn, B., Fan, Q., Yang, J.J., Henin, O.Petrogenesis of the Maowu pyroxenite eclogite body from the UHP metamorphic terrane of Dabie Shan: chemical and isotopic constraLithos, Vol. 70, 3-4, pp. 243-67.ChinaUHP, geochronology
DS1992-0702
1992
Henjeskunst, F.Henjeskunst, F., Altherr, R.Metamorphic petrology of xenoliths from Kenya and northern Tanzania And implications for geotherms and lithospheric structuresJournal of Petrology, Vol. 33, No. 5, October pp. 1125-1156Tanzania, KenyaXenoliths, GeotherM.
DS1998-0611
1998
Henjes-Kunst, F.Henjes-Kunst, F., Markl, G.Charnockitic intrusive rocks and related lamprophyres in central DronningMaud Land, East Antarctica...Journal of African Earth Sciences, Vol. 27, 1A, p. 110. AbstractAntarcticaMagmqatisM., Pan-African Orogeny
DS1999-0330
1999
Henjes-Kunst, F.Jacobs, J., Thomas, R.J., Henjes-Kunst, F.Age and thermal evolution of the Mesoproterozoic Cape Meredith Complex, West Falkland.Journal of Geological Society of London, Vol. 156, No. 3, May pp. 917-28.GlobalGeochronology
DS201112-0271
2011
Henjes-Kunst, F.Do Cabo, V., Sitnikova, M.A., Ellmies, R., Wall, F., Henjes-Kunst, F., Gerdes, A.Geological and geochemical characteristics of carbonatites of Lofdal, Namibia.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterAfrica, NamibiaCarbonatite
DS201112-0272
2011
Henjes-Kunst, F.Do Cabo, V., Sitnikova, M.A., Elmies, R., Wall, F., Henjes-Kunst, F., Gerdes, A.Geological and geochemical characteristics of carbonatites of Lofdal, NamibiaPeralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.140-143.Africa, NamibiaLofdal
DS201112-0273
2011
Henjes-Kunst, F.Do Cabo, V., Sitnikova, M.A., Elmies, R., Wall, F., Henjes-Kunst, F., Gerdes, A.Geological and geochemical characteristics of carbonatites of Lofdal, NamibiaPeralk-Carb 2011... workshop June 16-18, Tubingen, Germany, Abstract p.140-143.Africa, NamibiaLofdal
DS201112-0274
2011
Henjes-Kunst, F.Do Cabo, V.N., Wall, F., Sitnikova, M.A., Ellmies, R., Henjes-Kunst, F., Gerdes, A., Downes, H.Mid and heavy REE in carbonatites at Lofdal, Namibia.Goldschmidt Conference 2011, abstract p.770.Africa, NamibiaCarbonatite, dykes
DS201312-0923
2013
Henjes-Kunst, F.Tribuzio, R., Henjes-Kunst, F., Braga, R., Tiepolo, M.Boninite derived mafic ultramafic intrusives from northern Victoria Land ( Antarctica): implications for mantle source metasomatism.Goldschmidt 2013, 1p. AbstractAntarcticaBoninites
DS1988-0299
1988
Henk, A.Henk, A., Lorenz, V.Experimental modelling of Maar-diatreme formationTerra Cognita, Vol. 8, No. 1, Winter 1988 p. 65. Abstract onlyGlobalBlank
DS1984-0754
1984
Henk, F.H.JR.Walper, J.L., Henk, F.H.JR.Double Indentation Tectonic Model for Suturing of North And south America and Formation of the Ouachita Orogenic Belt.Geological Society of America (GSA), Vol. 16, No. 2, FEBRUARY P. 116. (abstract.).GlobalMid-continent
DS1991-0706
1991
Henkel, H.Henkel, H.Magnetic crustal structures in northern FennoscandiaTectonophysics, Vol. 192, No. 1-2, June 10, pp. 57-80Norway, SwedenGeophysics -magnetics, Structure
DS1994-0762
1994
Henkel, H.Henkel, H.Standard diagrams of magnetic properties and density - a tool for understanding magnetic petrologyJournal of Applied Geophysics, Vol. 32, pp. 43-53Norway, Finland, SwedenPetrology, Geophysics -magnetics
DS1998-0612
1998
Henkel, H.Henkel, H., Reimold, W.U.Integrated geophysical modeling of a giant, complex impact structure:anatomy of the Vredefort structureTectonophysics, Vol. 287, No. 1-4, Mar. 20, pp. 1-20South AfricaStructure, Vredefort
DS1988-0327
1988
Henkel, J.Jaskolla, F., Henkel, J.Evaluation and digital processing of multispectral SPOT dataInternational Journal of Remote Sensing, Vol. 9, No. 10-11, Oct-Nov. pp. 1629-1638GlobalRemote Sensing, Computer -SPOT.
DS200712-0169
2007
Henkel, T.Chatzitheodoridis, E., Kostopoulos, D., Lyon, I., Henkel, T., Cornelius, N., Baltatzis, E., Reischmann, T.Elemental distributions in zircons from Diamondiferous UHPM rocks from the Greek Rhodope: a TOF-SIMS study.Plates, Plumes, and Paradigms, 1p. abstract p. A163.Europe, GreeceUHP
DS1859-0010
1744
Henkels, J.F.Henkels, J.F.Views on the Formation of Mineral Materials, Including Gemstones and Coral.Dressden And Leipzig:, 619P.GlobalKimberley
DS1995-1581
1995
Henley, R.Rix, S., Henley, R.Thinking discovery - is your mind trained for successful explorationAustralian Institute of Mining and Metallurgy (AusIMM) Bulletin, No. 1, Feb, pp. 76-80AustraliaEconomics, Exploration philosophy -brain power
DS1992-0703
1992
Henley, S.Henley, S., Aucott, J.W.Some alternatives to geostatistics for mining and explorationInstitute of Mining and Metallurgy (IMM)Transactions, Vol. 101, pp. A 36-A40GlobalGeostatistics, Soft-kriging
DS200612-0567
2006
Henley, S.Henley, S.The problem of missing dat a in geoscience dat abases.Computers & Geosciences, in pressTechnologyFuzzy logic
DS201312-0378
2013
Henn, S.Henn, S.Transnational entrepreneurs and the emergence of clusters in peripheral regions, The case of the diamond cutting cluster in Gujarat, India.European Planning Studies, Vol. 21, 11, pp. 1779-1795.IndiaDiamond cutting
DS1950-0027
1950
Hennessey, M.N.Hennessey, M.N.Diamond Mining by Gold Coast AfricansCrown Colonist., Vol. 20, No. 224, JULY PP. 422-423.West Africa, Gold Coast, BonsahGeology, Alluvial Diamond Placers
DS201803-0432
2018
Hennet, L.Andrault, D., Pesce, G., Manthilake, G., Monteux, J., Volfan-Casanova, N., Chantel, J. , Novella, D., Guignot, N., King, A., Itie, J-P., Hennet, L.An archean mushy mantle.Nature Geoscience, Vol. 11, 2, pp. 85-86.Mantlegeodynamics

Abstract: Experimental data reveal that Earth’s mantle melts more readily than previously thought, and may have remained mushy until two to three billion years ago.
DS1988-0578
1988
Henney, P.J.Rock, N.M.S., Gaskarth, J.W., Henney, P.J., Shand, P.Late Caledonian dyke swarms of northern Britain: some preliminary petrogeneic and tectonic implications of their province wide distribution andchemicCanadian Mineralogist, Vol. 26, No. 1, March pp. 3-22GlobalBlank
DS1996-0465
1996
Henney, P.J.Fowler, M.B., Henney, P.J.Mixed Caledonian appinite magmas: implications for lamprophyre fractionation and high BaSr granite genesisContributions to Mineralogy and Petrology, Vol. 126, pp. 199-215.ScotlandLamprophyres
DS2003-0577
2003
Henning, A.Henning, A., Kiviets, G., Kurszlaukis, S., Barton, E., Mayaga-Mikolo, F.Early Proterozoic metamorphosed kimberlites from Gabon8 Ikc Www.venuewest.com/8ikc/program.htm, Session 7, AbstractGabonKimberlite petrogenesis
DS200412-0818
2003
Henning, A.Henning, A., Kiviets, G., Kurszlaukis, S., Barton, E., Mayaga-Mikolo, F.Early Proterozoic metamorphosed kimberlites from Gabon.8 IKC Program, Session 7, AbstractAfrica, GabonKimberlite petrogenesis
DS201212-0339
2012
Henning, A.Jelsma, H.,Krishnan, S.U., Perritt, S.,Kumar, M., Preston, R., Winter, F., Lemotlo, L., Costa, J., Van der Linde, G., Facatino, M., Posser, A., Wallace, C., Henning, A., Joy, S., Chinn, I., Armstrong, R., Phillips, D.Kimberlites from central Angola: a case stidy of exploration findings.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractAfrica, AngolaOverview of kimberlites
DS201412-0427
2013
Henning, A.Jelsma, H., Krishnan, U., Perritt, S., Preston, R., Winter, F., Lemotlo, L., van der Linde, G., Armstrong, R., Phillips, D., Joy, S., Costa, J., Facatino, M., Posser, A., Kumar, M., Wallace, C., Chinn, I., Henning, A.Kimberlites from central Angola: a case study of exploration findings.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 173-190.Africa, AngolaExploration - kimberlites
DS201212-0294
2012
Henning, O.Henning, O.,Sorensen, S.S., Hakin, S., Pedersen, B.oC., Christiansen, Z.I.Non destructive identification of micrometer scale minerals and their position within a bulk sample.Canadian Mineralogist, Vol. 50, 2, pp. 501-509.TechnologyMicrotomography
DS1998-0613
1998
Henning, Th.Henning, Th., Salawa, F.Carbon in the universeScience, Vol. 282, No. 5397, Dec. 18, pp. 2204-10.MantleCarbon
DS2002-1726
2002
HennionWinkler, B., Knorr, Kahle, Vontobel, Lehmann, HennionNeutron imaging and neutron tomography as non-destructive tools to study bulk rock samples.European Journal of Mineralogy, Vol.14,2,pp.349-54.GlobalTechnology
DS2002-1727
2002
HennionWinkler, B., Knorr, Kahle, Vontobel, Lehmann, HennionNeutron imaging and neutron tomography as non-destructive tools to study bulk rock samples.European Journal of Mineralogy, Vol. 14,pp.349-54., Vol. 14,pp.349-54.GlobalTomography - neutron imaging - not specific to diamonds
DS2002-1728
2002
HennionWinkler, B., Knorr, Kahle, Vontobel, Lehmann, HennionNeutron imaging and neutron tomography as non-destructive tools to study bulk rock samples.European Journal of Mineralogy, Vol. 14,pp.349-54., Vol. 14,pp.349-54.GlobalTomography - neutron imaging - not specific to diamonds
DS201412-0010
2014
Henot, J-M.Andrault,D., Pesce, G., Ali Bouhifd, M., Bolfan-Casanova, N., Henot, J-M., Mezouar, M.Melting of basalt at the core-mantle boundary.Science, Vol. 344, no. 6186, pp. 892-895.MantleSubduction
DS1984-0389
1984
Henriksen, N.Kalsbeek, F., Taylor, P.N., Henriksen, N.Age of rocks, structures and metamorphism in the Nagssugtoqidian Mobile belt - fold and lead isotope evidence.Canadian Journal of Earth Sciences, Vol. 21, pp. 1126-31.Greenland, WesternGeochronology
DS1970-0530
1972
Henriques, R.C.Henriques, R.C.Crystallographic Studies of Kimberlite Minerals of Varying Chemical composition.Ph.d. Thesis University London., 325P.GlobalCrystallography, Mineralogy
DS1997-0113
1997
Henry, B.Borradaile, G.J., Henry, B.Tectonic applications of magnetic susceptibilty and its anisotropyEarth Science Reviews, Vol. 42, pp. 49-93GlobalMagnetic susceptibility - AMS, Tectonics
DS2001-0246
2001
Henry, B.Derder, M.E.M., Henry, B., Merabet, N., Amenna, BouroisUpper Carboniferous paleomagnetic pole from the stable Saharan Craton and Gondwana reconstructions.Journal of African Earth Science, Vol. 32, No. 3, Apr. pp. 491-502.South AfricaGeophysics - paleomagnetism, Gondwanaland
DS2002-0123
2002
Henry, B.Bayou, B., Derder, M.E., Henry, B., Djellit, H.,AmennaPremier pole paleomagnetique d'age Mosvien constraint par un test du pli, obtenu dans le bassin d'Illizi.Comptes Rendus Geosciences, Vol.334,2,pp. 81-7.AlgeriaCraton - Sahara, Paleomagnetism
DS1986-0358
1986
Henry, C.D.Henry, C.D., McDowell, F.W., Price, J.G., Smyth, R.C.Compilation of potassium argon ages of Tertiary igneous rocks,Trans PecosTexasTexas Bur. Econ. Geol, Geol. Circular, No. 86-2, 20pGlobalGeochronology
DS1986-0653
1986
Henry, C.D.Price, J.G., Henry, C.D., Parker, D.F., Barker, D.S.Igneous geology of Trans Pecos TexasTexas Bur. of Economic Geology, Guidebook, No. 23, 100pGlobalBlank
DS1987-0595
1987
Henry, C.D.Price, J.G., Henry, C.D., Barker, D.S., Parker, D.F.Alkalic rocks of contrasting tectonic settings in Trans Pecos TexasMantle metasomatism and alkaline magmatism, edited E. Mullen Morris and, No. 215, pp. 335-346GlobalAnalyses p. 340
DS1993-0736
1993
Henry, C.D.James, E.W., Henry, C.D.Southeastern extent of the North American craton in Texas and northern Chihuahua as revealed by lead isotopesGeological Society of America (GSA) Bulletin, Vol. 105, No. 1, January pp. 116-126Texas, MexicoCraton, tectonics
DS1993-1341
1993
Henry, C.D.Rubin, J.N., Henry, C.D., Price, J.G.The mobility of zirconium and other immobile elements during hydrothermalalterationChemical Geology, Vol. 110, No. 1/3, November 25, pp. 29-48GlobalAlteration -hydrothermal, Zircon
DS2003-1294
2003
Henry, C.D.Sloan, J., Henry, C.D., Hopkins, M., Ludington, S.National geochronological database. Original databse by Zartman, Bush and AbstonU.s.g.s. Open File, Http://geopubs.wr.usgs.gov/open-file/of3-236, United StatesGeochronology - database ( not specific to diamonds)
DS200412-1854
2003
Henry, C.D.Sloan, J., Henry, C.D., Hopkins, M., Ludington, S.National geochronological database. Original databse by Zartman, Bush and Abston.U.S. Geological Survey, United StatesGeochronology - database ( not specific to diamonds)
DS1994-0475
1994
Henry, D.Dutrow, B., Cash, T., Henry, D.Crystal chemistry of charoite: a product of intense metasomatic processesGeological Society of America (GSA) Abstract Volume, Vol. 26, No. 7, ABSTRACT only p. A481.RussiaCharoite, Little Murun alkaline
DS1950-0104
1952
Henry, D.J.Henry, D.J.Gem Trail JournalCalifornia: Long Beach, Second Edition., 93P.United States, California, West CoastBlank
DS201412-0601
2013
Henry, D.J.Mueller, P.A., Mogk, D.W., Henry, D.J., Wooden, J.L., Foster, D.A.The plume to plate transition: Hadean and Archean crustal evolution in the northern Wyoming province, USA.Dilek & Furnes eds. Evolution of Archean crust and early life. Springer Publication, pp. 23-54.United StatesMantle plume
DS1983-0218
1983
Henry, F.Eupene Exploration Enterprises, Geopeko Ltd., Henry, F.El 2885 Final Report on Exploration 1982-1983Northern Territory Geological Survey Open File Report, No. CR 83/269, 16P.Australia, Northern TerritoryProspecting, Sampling, Geochemistry
DS1990-0685
1990
Henry, G.Henry, G., Clendenin, C.W., Stainstreet, I.G., Maiden, K.J.Multiple detachment model for the early rifting stAge of Late Proterozoic Damara orogen in NamibiaGeology, Vol. 18, No. 1, January pp. 67-71Southwest Africa, NamibiaTectonics, Damara orogen
DS1991-1654
1991
Henry, G.Stanistreet, I.G., Kukla, P.A., Henry, G.Sedimentary basinal responses to a Late Precambrian Wilson Cycle: the Damara Orogen and Nama Foreland, NamibiaJournal of African Earth Sciences, Vol. 13, No. 1, pp. 141-156Namibia, Southwest AfricaOrogeny, Wilson Cycle
DS200712-1163
2006
Henry, G.Wilson, M.G.C., Henry, G.A review of the alluvial diamond industry and the gravels of the North West province, South Africa.South African Journal of Geology, Vol. 109, 3, Sept. pp. 301-314.Africa, South AfricaReview - Schweizer-Reneke, Lichtenburg, Ventersdorp
DS201709-1998
2017
Henry, H.Henry, H., Afonso, J.C., Satsukawa, T., Griffin, W.L., O'Reilly, S.Y., Kaczmarek, M-A., Tilhac, R., Gregoire, M., Ceuleneer, G.The unexplored potential impact of pyroxenite layering on upper mantle seismic properties.Goldschmidt Conference, abstract 1p.Europe, Spain, United States, Californiageophysics - seismics

Abstract: It is now accepted that significant volumes of pyroxenites are generated in the subduction factory and remain trapped in the mantle. In ophiolites and orogenic massifs the geometry of pyroxenite layers and their relationships with the host peridotite can be observed directly. Since a large part of what is known about the upper mantle structure is derived from the analysis of seismic waves, it is crucial to integrate pyroxenites in the interpretations. We modeled the seismic properties of a peridotitic mantle rich in pyroxenite layers in order to determine the impact of layering on the seimsic properties. To do so, EBSD data on deformed and undeformed pyroxenites from the Cabo Ortegal complex (Spain) and the Trinity ophiolite (California, USA) respectively are combined with either A or B-type olivine fabrics in order to model a realistic pyroxenite-rich upper mantle. Consideration of pyroxeniterich domains within the host mantle wall rock is incorporated in the calculations using the Schoenberg and Muir group theory [1]. This quantification reveals the complex dependence of the seismic signal on the deformational state and relative abundance of each mineral phase. The incorporation of pyroxenites properties into geophysical interpretations in understanding the lithospheric structure of subduction zones will lead to more geologically realistic models.
DS201906-1293
2019
Henry, H.Gain, S.E.M., Greau, Y., Henry, H., Belousova, E., Dainis, I., Griffin, W.L., O'Reilly, S.Y.Mud Tank zircon: long term evaluation of a reference material for U-Pb dating, Hf-isotope analysis and trace element analysis. ( Carbonatite)Geostandards and Geoanalytical Research, in press available, 16p.Australiadeposit - Mud Tank

Abstract: Zircon megacrysts from the Mud Tank carbonatite, Australia, are being used in many laboratories as a reference material for LA?ICP?MS U?Pb dating and trace element measurement, and LA?MC?ICP?MS determination of Hf isotopes. We summarise a database of > 10000 analyses of Mud Tank zircon (MTZ), collected from 2000 to 2018 during its use as a secondary reference material for simultaneous U?Pb and trace element analysis, and for Hf?isotope analysis. Trace element mass fractions are highest in dark red?brown stones and lowest in colourless and gem?quality ones. Individual unzoned grains can be chemically homogeneous, while significant variations in trace element mass fraction are associated with oscillatory zoning. Chondrite?normalised trace element patterns are essentially parallel over large mass fraction ranges. A Concordia age of 731.0 ± 0.2 Ma (2s, n = 2272) is taken as the age of crystallisation. Some grains show lower concordant to mildly discordant ages, probably reflecting minor Pb loss associated with cooling and the Alice Springs Orogeny (450-300 Ma). Our weighted mean 176Hf/177Hf is 0.282523 ± 10 (2s, n = 9350); the uncertainties on this ratio reflect some heterogeneity, mainly between grains. A few analyses suggest that colourless grains have generally lower 176Hf/177Hf. MTZ is a useful secondary reference material for U?Pb and Hf?isotope analysis, but individual grains need to be carefully selected using CL imaging and tested for homogeneity, and ideally should be standardised by solution analysis.
DS202008-1398
2020
Henry, H.Greene, S., Jacob, D.E., O'Reilly, S.Y., Henry, H., Pinter, Z., Heaman, L.Extensive prekimberlitic lithosphere modification recorded in Jericho mantle xenoliths in kimberlites, Slave Craton.Goldschmidt 2020, 1p. AbstractCanada, Northwest Territoriesdeposit - Jericho

Abstract: Wehrlite and pyroxenite xenoliths and megacrysts from the Jericho kimberlite were analyzed by ?XRF and EBSD, and for major elements, trace elements, and isotopes (Pb-Sr- O) in major phases. Thermobarometry places these samples at 60 - 180 km and 600 - 1200 ??C. While modes and textures vary, many samples have olivine-olivine grain boundaries with straight edges and 120° angle junctions, indicating granoblastic recrystallisation, while clinopyroxene and orthopyroxene are complexly intergrown. Clinopyroxene twins and subgrains recording orientations distinct from the encapsulating grain were detected using EBSD and are inferred to represent recent modification processes. Several distinct garnet compositions were measured, with multiple thin garnet rims in some samples suggesting possible successive stages of garnet crystallisation. Complex chromium zoning in garnet is detected by ?XRF in several samples (fig.1). Pb-Pb ages for most samples are similar to the age of kimberlite entrainment (173 Ma), but the shallowest pyroxenite sample preserves the most radiogenic Pb composition, intercecting concordia at 0.7 - 1.1 Ga, and is the only sample with ?18O above the mantle range (6.2±0.1 ‰). The deepest sample has the lowest ?18O (5.5±0.1 ‰) and radiogenic 87Sr/86Sr similar to MARID rocks (0.709±1 ‰). These results suggest the Jericho lithosphere experienced several melt/fluid injection events that modified substantial portions of the sampled section soon before kimberlite entrainment.
DS1996-1127
1996
Henry, J.J.Pollock, S.H., Henry, J.J.Mineral extraction and United Kingdom policies for sustainabledevelopmentMinerals Industry International, January pp. 13-16GlobalEconomics, Sustainability
DS1989-0624
1989
Henry, M.E.Henry, M.E.Review of the geology of the southern Oklahoma foldbelt province as abasis for estimates of undiscovered hydrocarbon resourcesUnited States Geological Survey (USGS) Open File, No. 87-045, 21p. $ 3.25GlobalTectonics
DS1993-0895
1993
Henry, P.Le Pichon, X., Henry, P., Lallemant, S.Accretion and erosion in subduction zones: the role of fluidsAnnual Review of Earth and Planetary Sciences, Vol. 21, pp. 307-332MantleTectonics
DS1996-1373
1996
Henry, P.Stevenson, R., Henry, P., Gariepy, C.Micro-continents and cratons: crustal evolution in the western SuperiorProvince.Geological Association of Canada (GAC) Annual Abstracts, Vol. 21, abstract only p.A91.OntarioCraton, Crustal evolution
DS1998-0614
1998
Henry, P.Henry, P., Stevenson, R.K., Gariepy, C.Late Archean mantle composition and crustal growth in the Western Superior Province of Canada: Neodynium and lead ...Geochimica et Cosmochimica Acta, Vol. 62, No. 1, pp. 143-157OntarioGeochronology, Wawa, Wabigoon subprovinces
DS1998-1411
1998
Henry, P.Stevenson, R., Henry, P., Gariepy, C.Late Archean cratonic evolutionGeological Association of Canada (GAC)/Mineralogical Association of Canada (MAC) Abstract Volume, p. A180. abstract.Ontario, ManitobaSuperior Province, Craton
DS1998-1470
1998
Henry, P.Tomlinson, K.Y., Stevenson, R.K., Henry, P.The Red Lake GS: evidence of plume related magmatism at 3 Ga and evidence of an older enriched sourcePrecambrian Research, Vol. 89, No. 1-2, May pp. 59-76Ontario, Superior ProvinceGreenstone Belt, Plumes, magmas
DS1999-0714
1999
Henry, P.Stevenson, R.K., Henry, P., et al.Archean crustal growth and tectonics in the western Superior ProvinceGeological Association of Canada (GAC) Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)., Vol. 24, p. 122. abstractOntarioTectonics, Superior Craton
DS2000-0405
2000
Henry, P.Henry, P., Stevenson, R.K., Gariepy, C.neodymium isotopic evidence for Early to late Archean (3.4-2.7 Ga) crustal grow thin Western Superior Province OntarioTectonophysics, Vol.322, No.1-2, July10, pp.135-52.OntarioGeochronology, Superior Province
DS2000-0406
2000
Henry, P.Henry, P., Stevenson, R.K., Larbi, Y., Gariepy, C.neodymium isotopic evidence for Early to Late Archean (3.4-2.7Ga) crustal growth in Western Superior ProvinceTectonophysics, Vol. 322, No. 1-2, pp.135-51.OntarioGeochronology, Tectonics
DS2001-0264
2001
Henry, P.Doin, M.P., Henry, P.Subduction initiation and continental crust recycling: the roles of rheology and eclogitization.Tectonophysics, Vol. 342, No. 2, pp. 163-91.MantleEclogites, Subduction
DS2001-0472
2001
Henry Birks and Sons Inc.Henry Birks and Sons Inc.Birks leads the way with Canadian mined diamond jewellery ProgramBirks and Sons Jewellers, Jan. 8, 2p.CanadaNews item, Diamond - sales
DS1994-1917
1994
Hensel, H.D.Wilkinson, J.F.G., Hensel, H.D.Nephelines and analcines in some alkaline igneous rocksContributions to Mineralogy and Petrology, Vol. 118, No. 1, Oct. pp. 79-91.AustraliaAlkaline rocks
DS1990-1070
1990
Hensen, B.J.Motoyoshi, Y., Hensen, B.J.Metastable growth of corundum adjacent to quartz in aspinel-bearingquartzite from the Archaean NapierComplex, AntarcticaJournal of Metamorphic Geology, Vol. 8, pp. 125-130AntarcticaNapier Complex
DS2000-0159
2000
Hensen, B.J.Clark, D.J., Hensen, B.J., Kinny, P.D.Geochronological constraints for a two stage history of the Albany Fraser Orogen, Western Australia.Precambrian Research, Vol. 102, No. 3-4, Aug.pp. 155-83.Australia, Western AustraliaGeochronology, Orogeny
DS2002-0237
2002
Hensen, B.J.Camacho, A., Hensen, B.J., Armstrong, R.Isotopic test of a thermally driven intraplate orogenic model, AustraliaGeology, Vol. 30, 10, Oct. pp. 887-90.AustraliaOrogenesis, basins, geothermometry
DS1950-0217
1955
Henshaw, D.E.Henshaw, D.E.The Structure of WadeiteMineralogical Magazine., Vol. 30, PP. 585-595.AustraliaLeucite, Lamproite
DS1950-0355
1957
Hensley, F.S.JRShoemaker, E.M., Hensley, F.S.JR, Hallagan, R.W.Diatremes on the Navajo and Hopi Reservation, Arizona. #2United States Geological Survey (USGS) SPECIAL Publishing, No. TEI-690, PP. 389-398.United States, Arizona, Colorado Plateau, Rocky MountainsDiatreme
DS1991-1546
1991
Henson, H.Sexton, J., Henson, H.Lake Superior bedrock topography and rift structuresGeological Society of America Annual Meeting Abstract Volume, Vol. 23, No. 5, San Diego, p. A 138OntarioTectonics, Rifting
DS1994-1570
1994
Henson, H.Jr.Sexton, J.L., Henson, H.Jr.Interpretation of seismic reflection and gravity profile dat a in western Lake Superior.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 652-660.Ontario, MichiganGeophysics -seismics, gravity, Tectonics -Midcontinent rift
DS1940-0007
1940
Henson, P.Henson, P.Arkansaw Diamond FieldGems And Gemology, Vol. 3, No. 7, PP. 109-112.United States, Gulf Coast, Arkansas, PennsylvaniaDiamond Occurrence, Geology
DS200512-0350
2004
Henson, P.Goleby, B.R., Blewett, R.S., Korsch, R.J., Champion, D.C., Cassidy, K.F., Jones, L.E., Groenewald, P.B., Henson, P.Deep seismic reflection profiling in the Archean northeastern Yilgarn Craton: implications for crustal architecture and mineral potential.Tectonophysics, Vol. 388, 1-4, pp. 119-133.AustraliaGeophysics - seismics, not specific to diamonds
DS2002-0596
2002
HenstockGorman, D., Clowes, Ellis, Henstock, Spence, KellerDeep probe: imaging the roots of western North AmericaCanadian Journal of Earth Science, Vol.39,3,Mar.pp.375-98., Vol.39,3,Mar.pp.375-98.Alberta, Montana, Colorado, CordilleraGeophysics - seismics, Tectonics
DS2002-0597
2002
HenstockGorman, D., Clowes, Ellis, Henstock, Spence, KellerDeep probe: imaging the roots of western North AmericaCanadian Journal of Earth Science, Vol.39,3,Mar.pp.375-98., Vol.39,3,Mar.pp.375-98.Alberta, Montana, Colorado, CordilleraGeophysics - seismics, Tectonics
DS1993-0654
1993
Henstock, T.J.Henstock, T.J., Woods, A.W., White, R.S.The accretion of oceanic crust by episodic sill intrusionJournal of Geophysical Research, Vol. 98, No. B 3, March 10, pp. 4143-4161MantleCrust, Seismic refraction data
DS1997-0650
1997
Henstock, T.J.Larkin, S.P., Levander, A. , Henstock, T.J.Is the MOHO flat? Seismic evidence for a rough crust-mantle interface beneath the north Basin -RangeGeology, Vol. 25, No. 5, May pp. 451-454United States, Basin and RangeGeophysics - seismics, Crust - mantle
DS1998-0865
1998
Henstock, T.J.Levander, A., Henstock, T.J., Snelson, C.M., KellerThe Deep Probe experiment; what is the role of inherited structure in the continents?Geological Society AmericanAnn.Meet., Vol. 30, No. 7, p. 161. abstract.Alberta, Western CanadaLithoprobe
DS1998-0866
1998
Henstock, T.J.Levander, A., Henstock, T.J., Snelson, Keller, GormanThe deep probe experiment: what is the role of inherited structure in thecontinents?Geological Society of America (GSA) Annual Meeting, abstract. only, p.A161.Northwest TerritoriesTectonics, Lithoprobe
DS1998-1364
1998
Henstock, T.J.Snelson, C.M., Henstock, T.J., Keller, Miller, LevanderCrustal and uppermost mantle structure along the Deep Probe seismic profileRocky Mountain Geol., Vol. 33, No. 2, pp. 181-98.Alberta, Western CanadaGeophysics - seismics, Lithoprobe
DS2002-1021
2002
HentonMazzotti, S., Dragert, Hyndman, Miller, HentonGPS deformation in a region of high crustal seismicity: N. Cascadia forearcEarth and Planetary Science Letters, Vol.198,1-2,pp.41-8., Vol.198,1-2,pp.41-8.CordilleraGeophysics - seismics not specific to diamonds
DS2002-1022
2002
HentonMazzotti, S., Dragert, Hyndman, Miller, HentonGPS deformation in a region of high crustal seismicity: N. Cascadia forearcEarth and Planetary Science Letters, Vol.198,1-2,pp.41-8., Vol.198,1-2,pp.41-8.CordilleraGeophysics - seismics not specific to diamonds
DS1991-1382
1991
Hentschel, T.Priester, M., Hentschel, T.Technology and problems of small scale mining in South AmericaRaw Materials Alert, Vol. 8, No. 1, pp. 40-49Bolivia, ColumbiaMining -general, Economics
DS1995-0788
1995
Hepton, P.Hepton, P.Deep rotary cored boreholes in soils using wireline drillingGeoDrilling International, Vol. 3, No. 2, April pp. 5, 7, 9.GlobalDrilling, Alluvials -not specific to diamonds
DS1970-0531
1972
Hepworth, J.V.Hepworth, J.V.Can Mineral Grains Be Used to Recognize the Basement in Thekalahari?Botswana Geological Survey, JVH/1/72, 3P. (UNPUBL.)BotswanaProspecting, Geochemistry
DS1970-0714
1973
Hepworth, J.V.Hepworth, J.V.Report on a Visit to Orapa Mine, February 1973Botswana Geological Survey, JVH/5/73, 7P. (UNPUBL.)BotswanaProspecting, Mining Engineering
DS1975-0237
1976
Hepworth, J.V.Baldock, J.W., Hepworth, J.V., Marenga, B.S.I.Gold, Base Metals and Diamonds in BotswanaEconomic Geology, Vol. 71, No. 1, PP. 139-152;BotswanaKimberlite, Orapa
DS1975-0455
1977
Hepworth, J.V.Baldock, J.W., Hepworth, J.V., Marengwa, B.S.I.Resource Inventory of BotswanaBotswana Geological Survey, Vol. 4, 69P. PP. 49-57. (DIAMONDS).BotswanaKimberlite, Diamond Prospecting
DS201112-0431
2011
Hera, R.Hera, R.Understanding resource company lifecycles. Here are the basics.Resource World Magazine, August pp. 48-49.GlobalNews item - research
DS1989-0364
1989
Herail, G.Domergue, C., Fontan, F., Herail, G.Les techniques artisanales d'exploitation des gites alluviaux: analogies dans le temps et dans l'espaceChron. Rech. Min., (in French), No. 497, pp. 131-138GlobalPlacers, Mining technology -alluvials
DS1990-0411
1990
Herail, G.Domergue, C., Fontan, F., Herail, G.Les techiques artisanales d'exploitation des gitesalluviaux: analogies dans le temps et dans l'espace. (in French)Chron. Rech. Min., (in French), No. 497, pp. 131-138GlobalAlluvials, Placer mining
DS1996-0624
1996
Herail, G.Herail, G., Oller, J., Soler, P.Strike slip faulting, thrusting and related basins in the Cenozoic evolution of the southern branch OroclineTectonophysics, Vol. 259, No. 1-3, June 30, pp. 201-212BoliviaTectonics, Faulting, thrusting
DS1997-0060
1997
Herail, G.Baby, P., Rochat, P., Mascle, G., Herail, G.Neogene shortening contribution to crustal thickening in the back arc Of the Central AndesGeology, Vol. 25, No. 10, Oct., pp. 883-886Bolivia, AndesThrust systems, Tectonics, geophysics
DS2002-0760
2002
Herail, G.Jaillard, E., Herail, G., Monfret, T., Worner, G.Andean geodynamics: main issues and contributions from the 4th. ISAGTectonophysics, Vol.345, 1-4, Feb.15, pp. 1-15.AndesGeodynamics - brief review
DS200512-0422
2005
Herald TribuneHerald TribuneThousands flee as plague kills 61 miners... eastern Congo... open pit diamond mine.Herald Tribune, Feb. 19, 1/2p.Africa, Democratic Republic of CongoNews item - mining
DS1992-0725
1992
Heran, W.D.Hoover, D.B., Heran, W.D., Hill, P.L.The geophysical expression of selected mineral deposit modelsUnited States Geological Survey (USGS) Open File, No. 92-557, 140pUnited StatesGeophysics, Deposits
DS1994-0763
1994
Heran, W.D.Heran, W.D.Codicil to the geophysical expression of selected mineral deposit modelsUnited States Geological Survey (USGS) Open File, No. 94-174, 36p. $ 5.75United StatesGeophysics, Deposit -models
DS1992-0598
1992
Herb, J.A.Graebner, J.E., Jin, S., Kammlott, G.W., Herb, J.A., Gardiner, C.F.Large anisotropic thermal conductivity in synthetic diamond filmsNature, Vol. 359, No. 6394, October 1, pp. 401-402GlobalDiamond synthesis, CVD.
DS1995-2036
1995
Herbert, H.K.Watling, R.J., Herbert, H.K., Barrow, I.S., Thomas, A.G.Analysis of diamonds and indicator minerals for diamond exploration by laser ablation - inductively coupled..Analyst, May pp. 1357-62.Australia, South Africa, China, Zaire, RussiaSpectrometry - mass, Indicator minerals, garnets, chromites
DS1970-0532
1972
Herbert, I.Herbert, I.The Diamond Diggers. South Africa 1866 to the 1970'sLondon: Tom Stacey, 138P.South AfricaKimberley, Fiction
DS1985-0278
1985
Herbert, R.Herbert, R.Stony Repsonse to the Diamond Hoax (editorial)New Scientist., Vol. 106, No. 1458, MAY 30TH. PP. 43-44.United StatesBlank
DS200612-0386
2005
Herbert, R.Famin, V., Herbert, R., Philippot, P., Jolivet, L.Ion probe and fluid inclusions evidence for co-seismic fluid infiltration in a crustal detachment.Contributions to Mineralogy and Petrology, Vol. 150, 3, pp. 354-367.MantleGeochronology
DS1980-0170
1980
Herbert, S.Herbert, S.Diamonds; 1980Hove: East Sussex: Wayland Publishing, 72P.GlobalKimberlitekimlib, Janlib
DS1983-0301
1983
Herbert, S.Herbert, S.Improved Reconnaissance in Mineral ProspectingIndustrial Diamond Review., No. 5, PP. 262-266.IrelandDrilling, Gas, Sampling, Hydrocarbon
DS1986-0359
1986
Herbert, S.Herbert, S.Diamonds behind everymanIndustrial Diamond Review, Vol. 46, No. 3, pp. 106-107GlobalEconomics
DS1987-0289
1987
Herbert, S.Herbert, S.Diamonds broaden the horizonsCiv. Eng, July, p. 41, pp. 43-44GlobalIndustrial applications
DS1989-0625
1989
Herbert, S.Herbert, S.A look back down the GardenIndiaqua, No. 52, 1989/I, pp. 57-60GlobalDiamond exchange Hatton Garden, History
DS1975-1111
1979
Herbert, Y.Laurent, R., Herbert, Y.Paragenesis of Serpentine Assemblages in Harzburgite Tectonite and Dunite Cumulate from the Quebec Appalachians.Canadian Mineralogist., Vol. 17, No. 4, PP. 857-870.Canada, QuebecRelated Rocks
DS1900-0118
1902
Herbertson, J.Herbertson, J.Geological Reports from South AfricaGeographical Journal, Vol. 20, PP. 630-636.Africa, South AfricaRegional Geology
DS200812-0465
2008
Herbst, J.Herbst, J., Potapov, A., Hambidge, G., Rademan, J.Modeling of diamond liberation and damage for Debswana kimberlitic ores.Minerals Engineering, Vol. 21, 11, October pp. 766-789.Africa, BotswanaMining - mineral processing
DS1990-1210
1990
Herbst, J.A.Rajamani, K., Herbst, J.A.Control '90-mineral and metallurgical processingAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Book, 600p. approx. $ 70.00GlobalMineral processing, Control 90 - from meeting presentations
DS1993-0024
1993
Herbst, T.M.Allamandola, L.J., Sandford, S.A., Tielens, A.G.G.M., Herbst, T.M.Diamonds in dense molecular clouds: a challenge to the standard interstellar medium paradigM.Science, Vol. 260, April 2, pp. 64-66GlobalDiamond formation, Meteoritic
DS201312-0028
2013
Herceg, M.Artemieva, I., Herceg, M., Cherepanova, Y., Thybo, H.Compositional heterogeneity of the upper mantle beneath the Siberian craton: reconciling thermal, seismic and gravity data.Goldschmidt 2013, AbstractRussiaGeophysics
DS1991-0707
1991
Herchen, H.Herchen, H.First order Raman spectrum of diamond at high temperaturesPhys. Rev. B., Vol. 43, No. 14, May 15, pp. 1740-1744GlobalDiamond morphology, Raman spectroscopy
DS1998-1092
1998
HerdOliver, G.J.H., Johnson, S.P., Williams, I.S., HerdRelict 1.4 Ga oceanic crust in the Zambezi Valley: evidence Mesoproterozoic supercontinental fragmentationGeology, Vol. 26, No. 6, June pp. 571-3ZimbabweOrogenic belts, Archean Craton, Rodinia, tectonics, Chewore ophiolite
DS1998-1093
1998
HerdOliver, G.J.H., Johnson, Williams, HerdRelict 1.4 Ga oceanic crust in the Zambezi Valley: evidence for Mesoproterozoic supercontinental fragmentGeology, Vol. 26, No. 6, June pp. 571-3.ZimbabweArchean craton, Zambezi belt
DS2000-0407
2000
Herd, C.D.K.Herd, C.D.K., Peterson, R.C.Violet coloured diopside from southern Baffin Island, Nunavut CanadaCanadian Mineralogist, Vol. 38, pt. 5, Oct. pp. 1193-99.Northwest Territories, Nunavut, Baffin IslandMineral chemistry - not specific to diamonds
DS2002-0706
2002
Heredia, N.Heredia, N., Rodiguez Fernandez, L.R., GallasteguiGeological setting of the Argentine frontal Cordillera in the flat slab segment 30 - 31)Journal of South American Earth Sciences, Vol.15,1,Apr.pp.79-99.Chile, AndesSubduction, Slab
DS1994-0764
1994
Hergt, J.Hergt, J., Hawkesworth, C.The remobilization of continental mantle lithosphereScience Progress, Vol. 76, pp. 191-207.MantleLithosphere
DS200812-1264
2008
Hergt, J.Woodhead, J.D., Phillips, D., Hergt, J., Paton, C.African kimberlites revisited: in situ Sr isotope analysis of groundmass perovskite.Goldschmidt Conference 2008, Abstract p.A1035.Africa, South AfricaGeochronology
DS200912-0113
2008
Hergt, J.Chesler, R., Hergt, J., Phillips, D., Maas, R.The geochemistry of the West Australian, West Kimberley province lamproites.Geological Society of Australia Abstracts, Vol. 90, p. 35. abs.AustraliaLamproite
DS200912-0479
2009
Hergt, J.Matchan, E., Hergt, J., Phillips, D., Shee, S.The geochemistry, petrogenesis and age of an unusual alkaline intrusion in the western Pilbara craton, western Australia.Lithos, In press availableAustraliaGeochronology
DS200912-0480
2008
Hergt, J.Matchan, E., Hergt, J., Phillips, D., Shee, S.The age, geochemistry and petrogenesis of an unusual alkaline intrusion in the western Pilbara, western Australia.Geological Society of Australia Abstracts, Vol. 90, p. 36. abs.AustraliaAlkalic
DS201012-0858
2009
Hergt, J.Woodhead, J., Hergt, J., Phillips, D., Paton, C.African kimberlites revisited: in situ Sr isotope analysis of groundmass perovskite.Lithos, Vol. 112 S pp. 311-317.AfricaKaapvaal craton deposits
DS201112-1119
2011
Hergt, J.Woodhead, J., Hergt, J., Greig, A., Edwards, L.Subduction zone Hf anomalies: mantle messenger, melting artefact or crustal process?Earth and Planetary Science Letters, Vol. 304, 1-2, pp. 231-239.MantleSubduction
DS201212-0128
2012
Hergt, J.Chesler, R., Hergt, J., Woodhead, J., Phillips, D.Geochemistry and geochronology of Tanzanian kimberlites,10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, TanzaniaGroup 1 kimberlites
DS201212-0199
2012
Hergt, J.Felgate, M., Hergt, J., Phillips, D., Woodhead, J.The Brazilian kimberlite-kamafugite association: a new and improved geochronological and geochemical investigation.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractSouth America, BrazilRondonia, Mato Grosso, Gias, Minas Gerais samples
DS201412-0993
2014
Hergt, J.Woodhead, J., Hergt, J., Phillips, D.Carbonate metasomatism at the continental scale: insights from kimberlite hosted zircon megacrysts.Goldschmidt Conference 2014, 1p. AbstractMantleMetasomatism
DS201708-1583
2017
Hergt, J.Woodhead, J., Hergt, J., Guiliani, A., Phillips, D., Maas, R.Tracking continental style scale modification of the Earth's mantle using zircon megacrysts. KimberlitesGeochemical Perspectives Letters, Vol. 4, pp. 1-6.Africa, South Africa, Zimbabwemetasomatism, geochronology

Abstract: Metasomatism, the chemical alteration of rocks by a variety of melts and fluids, has formed a key concept in studies of the Earth’s mantle for decades. Metasomatic effects are often inferred to be far-reaching and yet the evidence for their occurrence is usually based upon individual hand specimens or suites of rocks that display considerable heterogeneity. In rare cases, however, we are offered insights into larger-scale chemical modifications that occur in the mantle. Here we utilise the Lu–Hf systematics of zircon megacrysts erupted in kimberlite magmas to discern two temporally and compositionally discrete metasomatic events in the mantle beneath southern Africa, each having an influence extending over an area exceeding one million km2. These data provide unambiguous evidence for metasomatic processes operating at continental scales and seemingly unperturbed by the age and composition of the local lithospheric mantle. The most recent of these events may be associated with the major Jurassic-Karoo magmatism in southern Africa.
DS201810-2315
2018
Hergt, J.Fitzpayne, A., Giuliani, A., Hergt, J., Phillips, D., Janney, P.New geochemical constraints on the origins of MARID and PIC rocks: implications for mantle metasomatism and mantle -derived potassic magmatism.Lithos, Vol. 318-319, pp. 478-493.Mantlemetasomatism
DS201812-2809
2018
Hergt, J.Fitzpayne, A., Giuliani, A., Hergt, J., Phillips, D., Janney, P.New geochemical constraints on the origins of MARID and PIC rocks: implications for mantle metasomatism and mantle derived potassic magmatism. ( kimberlite)Lithos, Vol. 318-319, pp. 478-493.Globallamproites

Abstract: MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) and PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks are unusual mantle samples entrained by kimberlites and other alkaline volcanic rocks. The formation of MARID rocks remains hotly debated. Although the incompatible element (for example, large ion lithophile element) enrichment in these rocks suggests that they formed by mantle metasomatism, the layered textures of some MARID samples (and MARID veins in composite xenoliths) are more indicative of formation by magmatic processes. MARID lithologies have also been implicated as an important source component in the genesis of intraplate ultramafic potassic magmas (e.g., lamproites, orangeites, ultramafic lamprophyres), due to similarities in their geochemical and isotopic signatures. To determine the origins of MARID and PIC xenoliths and to understand how they relate to alkaline magmatism, this study presents new mineral major and trace element data and bulk-rock reconstructions for 26 MARID and PIC samples from the Kimberley-Barkly West area in South Africa. Similarities between compositions of PIC minerals and corresponding phases in metasomatised mantle peridotites are indicative of PIC formation by pervasive metasomatic alteration of peridotites. MARID genesis remains a complicated issue, with no definitive evidence precluding either the magmatic or metasomatic model. MARID minerals exhibit broad ranges in Mg# (e.g., clinopyroxene Mg# from 82 to 91), which may be indicative of fractionation processes occurring in the MARID-forming fluid/melt. Finally, two quantitative modelling approaches were used to determine the compositions of theoretical melts in equilibrium with MARID rocks. Both models indicate that MARID-derived melts have trace element patterns resembling mantle-derived potassic magma compositions (e.g., lamproites, orangeites, ultramafic lamprophyres), supporting inferences that these magmas may originate from MARID-rich mantle sources.
DS201902-0271
2019
Hergt, J.Fitzpayne, A., Giuliani, A., Maas, R., Hergt, J., Janney, P., Phillips, D.Progressive metasomatism of the mantle by kimberlite melts: Sr-Nd-Hf-Pb isotope compositions of MARID and PIC minerals.Earth and Planetary Science Letters, Vol. 506, pp. 15-26.Africa, South Africadeposit - Newlands, Kimberley, Bultfontein

Abstract: MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) and PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks occur as mantle-derived xenoliths in kimberlites and other alkaline volcanic rocks. Both rock types are alkaline and ultramafic in composition. The H2O and alkali metal enrichments in MARID and PIC rocks, reflected in abundant phlogopite, have been suggested to be caused by extreme mantle metasomatism. Radiogenic (Sr-Nd-Hf-Pb) isotope and trace element compositions for mineral separates from MARID (clinopyroxene and amphibole) and PIC (clinopyroxene only) samples derived from Cretaceous kimberlites (Kimberley) and orangeites (Newlands) from South Africa are used here to examine the source(s) of mantle metasomatism. PIC clinopyroxene is relatively homogeneous, with narrow ranges in initial isotopic composition (calculated to the emplacement age of the host Bultfontein kimberlite; 87Sr/86Sri: 0.7037-0.7041; ?Ndi: +3.0 to +3.6; ?Hfi: +2.2 to +2.5; 206Pb/204Pbi: 19.72-19.94) similar to kimberlite values. This is consistent with PIC rocks representing peridotites modified by intense metasomatic interaction with kimberlite melts. The MARID clinopyroxene and amphibole separates () studied here display broader ranges in isotope composition (e.g., 87Sr/86Sri: 0.705-0.711; ?Ndi: ?11.0 to ?1.0; ?Hfi: ?17.9 to ?8.5; 206Pb/204Pbi: 17.33-18.72) than observed in previous studies of MARID rocks. The Nd-Hf isotope compositions of kimberlite-derived MARID samples fall below the mantle array (??Hfi between ?13.0 and ?2.4), a feature reported widely for kimberlites and other alkaline magmas. We propose that such displacements in MARID minerals result from metasomatic alteration of an initial “enriched mantle” MARID composition (i.e., 87Sr/86Sri = 0.711; ?Ndi = ?11.0; ?Hfi = ?17.9; and 206Pb/204Pbi = 17.3) by the entraining kimberlite magma (87Sr/86Sr; ?Nd; ?Hf; 206Pb/204Pb). A model simulating the flow of kimberlite magma through a mantle column, thereby gradually equilibrating the isotopic and chemical compositions of the MARID wall-rock with those of the kimberlite magma, broadly reproduces the Sr-Nd-Hf-Pb isotope compositions of the MARID minerals analysed here. This model also suggests that assimilation of MARID components could be responsible for negative ??Hfi values in kimberlites. The isotopic composition of the inferred initial MARID end-member, with high 87Sr/86Sr and low ?Nd, ?Hf, and 206Pb/204Pb, resembles those found in orangeites, supporting previous inferences of a genetic link between MARID-veined mantle and orangeites. The metasomatic agent that produced such compositions in MARID rocks must be more extreme than the EM-II mantle component and may relate to recycled material that experienced long-term storage in the lithospheric mantle.
DS201904-0736
2019
Hergt, J.Fitzpayne, A., Giuliani, A., Harris, C., Thomassot, E., Cheng, C., Hergt, J.Evidence for subduction related signatures in the southern African lithosphere from the N-O isotopic composition of metasomatic mantle minerals.Geochimica et Cosmochimica Acta, in press available 21p.Africa, South Africadeposit - Bultfontein

Abstract: Current understanding of the fate of subducted material (and related fluids) in the deep Earth can be improved by combining major and trace element geochemistry with stable isotopic compositions of mantle rocks or minerals. Limited isotopic fractionation during high temperature processes means that significant deviations from mantle-like isotope ratios in mantle rocks probably result from recycling of surficial material. To determine the effects and origins of mantle metasomatic fluids/melts, new ?15N and ?18O data have been collected for thirteen mantle xenoliths - harzburgites, wehrlites, lherzolites, and MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) rocks - from the Bultfontein kimberlite (Kimberley, South Africa), which show varying degrees of metasomatism. The ?18O values of olivine and orthopyroxene in phlogopite-free harzburgites match the mantle composition (?18Oolivine?=?+5.2?±?0.3‰; ?18Oorthopyroxene?=?+5.7?±?0.3‰; 2?s.d.), consistent with previous inferences that harzburgites were formed by interaction with ancient silica-rich melts unrelated to subduction processes. Wehrlite samples display mineral compositional characteristics (e.g., low La/Zr in clinopyroxene) resembling those of other products of kimberlite melt metasomatism, such as PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks. The inferred interaction with kimberlite melts may be responsible for O isotopic disequilibrium between clinopyroxene and olivine (?18O?=?+0.2‰) in the wehrlites of this study. In contrast with broadly mantle-like ?18O values, the ?15N value of phlogopite in a wehrlite sample (+5.9‰) differs from the mantle composition (?15N?=??5?±?2‰). This unusual N isotopic composition in kimberlite-related mantle products might indicate that a recycled crustal component occurred in the source of the Kimberley kimberlites, or was assimilated during interaction with the lithospheric mantle. Similar major and trace element characteristics in clinopyroxene from phlogopite-lherzolite and MARID samples suggest metasomatism by fluids of similar composition. Lherzolite and MARID clinopyroxene ?18O values (as low as +4.4‰) extend below those reported in mantle peridotites (i.e. ?18Oclinopyroxene?=?+5.6?±?0.3‰; 2?s.d.), and strong negative correlations are found between mineral ?18O values and major element compositions (e.g., Na2O contents in clinopyroxene). Furthermore, phlogopite ?15N values (+4 to +7‰) in the studied lherzolite and MARID samples are higher than mantle values. Combined, the low ?18O-high ?15N isotopic signatures of MARID and lherzolite samples suggest progressive mantle metasomatism by a melt containing a recycled oceanic crust (eclogitic) component. This study demonstrates that progressive enrichment of the subcontinental lithospheric mantle may be inextricably linked to plate tectonics via recycling of subducted crustal material into the deep mantle.
DS201910-2253
2019
Hergt, J.Dalton, H., Giuliani, A., Phillips, D., Hergt, J., O'Brien, H.Petrographic and geochemical variations in the Kaavi-Kuopio kimberlite field, Finland: the role of mantle assimilation.Goldschmidt2019, 1p. AbstractEurope, Finlanddeposit - Kaavi-Kuopio

Abstract: Kimberlites are silica-poor, volatile-rich (CO2 ± H2O), volcanic rocks that are often described as ‘hybrid’, because their parental magmas include abundant xenocrystic (crustand mantle-derived) components. Unravelling the influence of mantle assimilation on kimberlite melt compositions represents an outstanding question of kimberlite petrology. To address this issue, we have carried out a comprehensive geochemical and petrographic investigation of nine kimberlites from the Kaavi-Kuopio field in Finland, that were emplaced on the southern margin of the Karelian Craton in the Neoproterozoic (~550-600 Ma). Olivine is the dominant mineral phase in kimberlites (~50 vol.%) with cores mainly derived from the disaggregation of mantle peridotite. In contrast, olivine rims crystallise directly from the kimberlitic melt and their Mg# (Mg/(Mg+Fe)) typically show remarkable homogeneity within and between kimberlites of a single cluster and field (e.g., Lac de Gras). The Kaavi-Kuopio kimberlites appear to represent a unique case where there is a (statistically) significant difference between the average Mg# of olivine rims in different pipes (89.9 ± 0.2 to 88.5 ± 0.3). Importantly, the Mg# of olivine rims exhibit a strong correlation with the Mg# of olivine cores. Furthermore, the compositions of olivine cores (and rims) exhibit a strong correlation with those of spinel (e.g., Mg#, TiO2 contents). These geochemical variations correlate with the modal mineralogy of the kimberlites: for example, higher abundances of monticellite and lower abundances of ilmenite are associated with higher Mg# olivine. The robust relationship between entrained and assimilated lithospheric mantle material (i.e. olivine cores) and magmatic components (i.e. olivine rims, spinel, and other groundmass minerals) suggests that assimilation of lithospheric mantle has impacted the compositions of kimberlitic melts to a greater extent than previously recognised. These new data also suggest significant variations in the composition of the mantle lithosphere beneath the Kaavi-Kuopio kimberlites, which are spaced less than 10 km apart.
DS201910-2257
2019
Hergt, J.Fitzpayne, A., Giuliani, A., Maas, R., Hergt, J., Janney, P., Phillips, D.Progressive metasomatism of the mantle by kimberliitic melts: Sr-Nd-Hf-Pb isotopic composition of MARID and PIC minerals.Goldschmidt2019, 1p. AbstractMantlemetasomatism

Abstract: MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) and PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks occur as mantle-derived xenoliths in kimberlites and other alkaline volcanic rocks. Both rock types are alkaline and ultramafic in composition. The H2O and alkali metal enrichments in MARID and PIC rocks, reflected in abundant phlogopite, have been suggested to be caused by extreme mantle metasomatism. Radiogenic (Sr-Nd-Hf-Pb) isotope and trace element compositions for mineral separates from MARID (clinopyroxene and amphibole) and PIC (clinopyroxene only) samples derived from Cretaceous kimberlites (Kimberley) and orangeites (Newlands) from South Africa are used here to examine the source(s) of mantle metasomatism. PIC clinopyroxene ( n = 4 ) is relatively homogeneous, with narrow ranges in initial isotopic composition (calculated to the emplacement age of the host Bultfontein kimberlite; 87Sr/86Sri: 0.7037-0.7041; ?Ndi: +3.0 to +3.6; ?Hfi: +2.2 to +2.5; 206Pb/204Pbi: 19.72-19.94) similar to kimberlite values. This is consistent with PIC rocks representing peridotites modified by intense metasomatic interaction with kimberlite melts. The MARID clinopyroxene ( n = 9 ) and amphibole separates ( n = 11 ) studied here display broader ranges in isotope composition (e.g., 87Sr/86Sri: 0.705-0.711; ?Ndi: ?11.0 to ?1.0; ?Hfi: ?17.9 to ?8.5; 206Pb/204Pbi: 17.33-18.72) than observed in previous studies of MARID rocks. The Nd-Hf isotope compositions of kimberlite-derived MARID samples fall below the mantle array (??Hfi between ?13.0 and ?2.4), a feature reported widely for kimberlites and other alkaline magmas. We propose that such displacements in MARID minerals result from metasomatic alteration of an initial “enriched mantle” MARID composition (i.e., 87Sr/86Sri = 0.711; ?Ndi = ?11.0; ?Hfi = ?17.9; and 206Pb/204Pbi = 17.3) by the entraining kimberlite magma (87Sr/86Sr ? i 0.704 ; ?Nd ? i + 3.3 ; ?Hf ? i + 2.3 ; 206Pb/204Pb ? i 19.7 ). A model simulating the flow of kimberlite magma through a mantle column, thereby gradually equilibrating the isotopic and chemical compositions of the MARID wall-rock with those of the kimberlite magma, broadly reproduces the Sr-Nd-Hf-Pb isotope compositions of the MARID minerals analysed here. This model also suggests that assimilation of MARID components could be responsible for negative ??Hfi values in kimberlites. The isotopic composition of the inferred initial MARID end-member, with high 87Sr/86Sr and low ?Nd, ?Hf, and 206Pb/204Pb, resembles those found in orangeites, supporting previous inferences of a genetic link between MARID-veined mantle and orangeites. The metasomatic agent that produced such compositions in MARID rocks must be more extreme than the EM-II mantle component and may relate to recycled material that experienced long-term storage in the lithospheric mantle.
DS201910-2308
2019
Hergt, J.Woodhead, J., Hergt, J., Giuliani, A., Maas, R., Philips, D., Pearson, D.G., Nowell, G.Kimberlites reveal 2.5-nillion year evolution of a deep, isolated mantle reservoir.Nature, Vol. 573, pp. 578-581.Mantlemelting

Abstract: The widely accepted paradigm of Earth's geochemical evolution states that the successive extraction of melts from the mantle over the past 4.5 billion years formed the continental crust, and produced at least one complementary melt-depleted reservoir that is now recognized as the upper-mantle source of mid-ocean-ridge basalts1. However, geochemical modelling and the occurrence of high 3He/4He (that is, primordial) signatures in some volcanic rocks suggest that volumes of relatively undifferentiated mantle may reside in deeper, isolated regions2. Some basalts from large igneous provinces may provide temporally restricted glimpses of the most primitive parts of the mantle3,4, but key questions regarding the longevity of such sources on planetary timescales—and whether any survive today—remain unresolved. Kimberlites, small-volume volcanic rocks that are the source of most diamonds, offer rare insights into aspects of the composition of the Earth’s deep mantle. The radiogenic isotope ratios of kimberlites of different ages enable us to map the evolution of this domain through time. Here we show that globally distributed kimberlites originate from a single homogeneous reservoir with an isotopic composition that is indicative of a uniform and pristine mantle source, which evolved in isolation over at least 2.5 billion years of Earth history—to our knowledge, the only such reservoir that has been identified to date. Around 200 million years ago, extensive volumes of the same source were perturbed, probably as a result of contamination by exogenic material. The distribution of affected kimberlites suggests that this event may be related to subduction along the margin of the Pangaea supercontinent. These results reveal a long-lived and globally extensive mantle reservoir that underwent subsequent disruption, possibly heralding a marked change to large-scale mantle-mixing regimes. These processes may explain why uncontaminated primordial mantle is so difficult to identify in recent mantle-derived melts.
DS201911-2575
2019
Hergt, J.Woodhead, J., Hergt, J., Giuliani, A., Maas, R., Phillips, D., Pearson, D.G., Nowell, G.Kimberlites reveal 2.5 billion year evolution of a deep, isolated mantle reservoir.Nature , Vol. 573, pp. 578-581.Mantlediamond genesis

Abstract: The widely accepted paradigm of Earth's geochemical evolution states that the successive extraction of melts from the mantle over the past 4.5 billion years formed the continental crust, and produced at least one complementary melt-depleted reservoir that is now recognized as the upper-mantle source of mid-ocean-ridge basalts1. However, geochemical modelling and the occurrence of high 3He/4He (that is, primordial) signatures in some volcanic rocks suggest that volumes of relatively undifferentiated mantle may reside in deeper, isolated regions2. Some basalts from large igneous provinces may provide temporally restricted glimpses of the most primitive parts of the mantle3,4, but key questions regarding the longevity of such sources on planetary timescales—and whether any survive today—remain unresolved. Kimberlites, small-volume volcanic rocks that are the source of most diamonds, offer rare insights into aspects of the composition of the Earth’s deep mantle. The radiogenic isotope ratios of kimberlites of different ages enable us to map the evolution of this domain through time. Here we show that globally distributed kimberlites originate from a single homogeneous reservoir with an isotopic composition that is indicative of a uniform and pristine mantle source, which evolved in isolation over at least 2.5 billion years of Earth history—to our knowledge, the only such reservoir that has been identified to date. Around 200 million years ago, extensive volumes of the same source were perturbed, probably as a result of contamination by exogenic material. The distribution of affected kimberlites suggests that this event may be related to subduction along the margin of the Pangaea supercontinent. These results reveal a long-lived and globally extensive mantle reservoir that underwent subsequent disruption, possibly heralding a marked change to large-scale mantle-mixing regimes. These processes may explain why uncontaminated primordial mantle is so difficult to identify in recent mantle-derived melts.
DS201912-2779
2020
Hergt, J.Fitzpayne, A., Prytulak, J., Giuliani, A., Hergt, J.Thallium isotope composition of phlogopite in kimberlite hosted MARID and PIC mantle xenoliths.Chemical Geology, Vol. 531, 14p. PdfMantlemetasomatism

Abstract: MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) and PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks are rare mantle xenoliths entrained by kimberlites. Their high phlogopite modes (15 to ?100 vol.%) and consequent enrichments in alkali metals and H2O suggest a metasomatic origin. Phlogopite also has high concentrations (>0.2 ?g/g) of thallium (Tl) relative to mantle abundances (<3 ng/g). Thallium isotope ratios have proven useful in tracing the input of Tl-rich materials, such as pelagic sediments and altered oceanic crust, to mantle sources because of their distinct isotopic compositions compared to the peridotitic mantle. This study presents the first Tl isotopic compositions of well-characterised phlogopite separates from MARID and PIC samples to further our understanding of their genesis. The PIC rocks in this study were previously interpreted as the products of kimberlite melt metasomatism, whereas the radiogenic and stable N-O isotope systematics of MARID rocks suggest a parental metasomatic agent containing a recycled component. The ?205Tl values of phlogopite in both PIC (-2.7 ± 0.8; 2 s.d., n = 4) and MARID samples (-2.5 ± 1.3; 2 s.d., n = 21) overlap with the estimated mantle composition (-2.0 ± 1.0). PIC phlogopite Tl contents (?0.4 ?g/g) are suggestive of equilibrium with kimberlite melts (0.1-0.6 ?g/g Tl), based on partitioning experiments in other silica-undersaturated melts. Kimberlite Tl-?205Tl systematics suggest their genesis does not require a recycled contribution: however, high temperature-altered oceanic crust cannot be ruled out as a component of the Kimberley kimberlites’ source. Mantle-like ?205Tl values in MARID samples also seem to contradict previous suggestions of a recycled contribution towards their genesis. Recycled components with isotopic compositions close to mantle values (e.g., high temperature-altered oceanic crust) are still permitted. Moreover, mass balance mixing models indicate that incorporation into the primitive mantle of 1-30% of a low temperature-altered oceanic crust + continental crust recycled component or 1-50% of continental crust alone could be accommodated by the Tl-?205Tl systematics of the MARID parental melt. This scenario is consistent with experimental evidence and existing isotopic data. One PIC phlogopite separate has an extremely light Tl isotopic composition of -9.9, interpreted to result from kinetic isotopic fractionation. Overall, phlogopite is the main host mineral for Tl in metasomatised mantle and shows a very restricted range in Tl isotopic composition, which overlaps with estimates of the mantle composition. These results strongly suggest that negligible high temperature equilibrium Tl isotopic fractionation occurs during metasomatism and reinforces previous estimates of the mantle’s Tl isotopic composition.
DS202002-0173
2019
Hergt, J.Dalton, H., Giuliani, A., O'Brien, H., Phillips, D., Hergt, J.The role of lithospheric heterogeneity on the composition of kimberlite magmas from a single field: the case of Kaavi-Kuopio, Finland.Lithos, in press available, 61p. PdfEurope, Finlanddeposit - Kaavi-Kuopio

Abstract: Kimberlites are complex, ‘hybrid’ igneous rocks because their parental magmas entrain abundant crust- and mantle-derived components that can be readily assimilated during ascent to surface. Recent studies of olivine zonation patterns have shown compositional relationships between xenocrystic cores and magmatic rims, suggesting that kimberlite melt compositions might be controlled by assimilation of mantle material during emplacement. However, the nature and extent to which this process, as well as assimilation of crustal material, influences melt compositions within single kimberlite fields remains unclear. To address this issue, we have conducted a comprehensive geochemical and petrographic investigation of kimberlites from eight pipes in the Kaavi-Kuopio field in Finland, which were emplaced on the southern margin of the Karelian craton during the Neoproterozoic (~550-600 Ma). While magmatic olivine rims are usually homogeneous in composition within and between kimberlites of a single cluster and field (e.g., Lac de Gras), the Kaavi-Kuopio kimberlites appear to represent a unique case where there are statistically significant differences between the average Mg# of olivine rims in different pipes (89.9 ± 0.2 to 88.5 ± 0.3). Importantly, the Mg# of magmatic olivine rims exhibit a strong correlation with the Mg# of their mantle-derived xenocrystic cores. Furthermore, the compositions of olivine cores and rims exhibit a robust relationship with those of magmatic spinel (e.g., Mg#, TiO2 contents). These geochemical variations also align with the mineralogy of the kimberlites: whereby abundances of phlogopite and oxides (e.g., spinel) are negatively correlated with olivine rim Mg#. The robust relationship between entrained and assimilated lithospheric mantle material (i.e. olivine cores) and magmatic components (i.e. olivine rims, spinel, and groundmass mineral abundance), combined with numerical modelling suggests that up to 10 wt% assimilation of lithospheric mantle material has modified the compositions of the Kaavi-Kuopio kimberlites. These new data are also consistent with significant variations in the lithospheric mantle composition of the Karelian craton beneath the closely spaced (<10 km) kimberlites. Finally, in addition to mantle assimilation, formation of Si-Fe-rich mica in some of the examined kimberlites might be linked to late-stage increases in oxygen fugacity potentially enhanced by crustal contamination. This study shows for the first time that variable assimilation of mantle and crustal material can generate significant variations in kimberlites derived from seemingly similar sources.
DS202007-1140
2020
Hergt, J.Fitzpayne, A., Giuliani, A., Hergt, J., Woodhead, J.D., Maas, R.Isotopic analyses of clinopyroxene demonstrate the effects of mantle metasomatism upon the lithospheric mantle.Lithos, in press available, 77p. PdfAfrica, South Africadeposit - Kimberley

Abstract: The trace element and radiogenic isotope systematics of clinopyroxene have frequently been used to characterise mantle metasomatic processes, because it is the main host of most lithophile elements in the lithospheric mantle. To further our understanding of mantle metasomatism, both solution-mode Sr-Nd-Hf-Pb and in situ trace element and Sr isotopic data have been acquired for clinopyroxene grains from a suite of peridotite (lherzolites and wehrlites), MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside), and PIC (Phlogopite-Ilmenite-Clinopyroxene) rocks from the Kimberley kimberlites (South Africa). The studied mantle samples can be divided into two groups on the basis of their clinopyroxene trace element compositions, and this subdivision is reinforced by their isotopic ratios. Type 1 clinopyroxene, which comprises PIC, wehrlite, and some sheared lherzolite samples, is characterised by low Sr (~100-200 ppm) and LREE concentrations, moderate HFSE contents (e.g., ~40-75 ppm Zr; La/Zr < 0.04), and restricted isotopic compositions (e.g., 87Sr/86Sri = 0.70369-0.70383; ?Ndi = +3.1 to +3.6) resembling those of their host kimberlite magmas. Available trace element partition coefficients can be used to show that Type 1 clinopyroxenes are close to being in equilibrium with kimberlite melt compositions, supporting a genetic link between kimberlites and these metasomatised lithologies. Thermobarometric estimates for Type 1 samples in this study indicate equilibration depths of 135-160 km within the lithosphere, thus showing that kimberlite melt metasomatism is prevalent in the deeper part of the lithosphere beneath Kimberley. In contrast, Type 2 clinopyroxenes occur in MARID rocks and coarse granular lherzolites in this study, which derive from shallower depths (<135 km), and have higher Sr (~350-1000 ppm) and LREE contents, corresponding to higher La/Zr of > ~ 0.05. The isotopic compositions of Type 2 clinopyroxenes are more variable and extend from compositions resembling the “enriched mantle” towards those of Type 1 rocks (e.g., ?Ndi = ?12.7 to ?4.4). To constrain the source of these variations, in situ Sr isotope analyses of clinopyroxene were undertaken, including zoned grains in Type 2 samples. MARID and lherzolite clinopyroxene cores display generally radiogenic but variable 87Sr/86Sri values (0.70526-0.71177), which are correlated with Sr contents and La/Zr ratios, and which might be explained by the interaction between peridotite and melts from different enriched sources within the lithospheric mantle. Most notably, the rims of these Type 2 clinopyroxenes trend towards compositions similar to those of the host kimberlite and Type 1 clinopyroxene from PIC and wehrlites. These results are interpreted to represent clinopyroxene overgrowth during late-stage (shortly before/during entrainment) metasomatism by kimberlite magmas. Our study shows that a pervasive, alkaline metasomatic event caused MARID to be generated and harzburgites to be converted to lherzolite in the lithospheric mantle beneath the Kimberley area, which was followed by kimberlite metasomatism during Cretaceous magmatism. This latter event is the time at which discrete PIC, wehrlite, and sheared lherzolite lithologies were formed, and MARID and granular lherzolites were partly modified.
DS202007-1141
2020
Hergt, J.Fitzpayne, A., Prytulak, J., Giuliani, A., Hergt, J.Thallium content and isotopic composition of phlogopite in mantle derived MARID and PIC rocks.Chemical Geology, Vol. 531, 119347Mantlegeochronology
DS202008-1383
2020
Hergt, J.Dalton, H., Giuiani, A., Phillips, D., Hergt, J., Maas, R., Woodhead, J., Matchan, E., O'Brien, H.Kimberlite magmatism in Finland: distinct sources and links to the breakup of Rodinia.Goldschmidt 2020, 1p. AbstractEurope, Finlanddeposit - Kuusamo

Abstract: The Karelian Craton in Finland is host to (at least) two distinct pulses of kimberlite magmatism. Twenty kimberlite occurrences have so far been discovered on the southwest margin of the craton at Kaavi-Kuopio and seven kimberlites are located in the Kuusamo area within the core of the craton. Comprehensive radiometric age determinations (U-Pb, Ar- Ar and Rb-Sr) reveal that all kimberlite activity was restricted to the Proterozoic. The Kaavi-Kuopio field was emplaced over a protracted period from ~610 to 550 Ma and is predated by the Kuusamo cluster that represents a relatively short pulse of magmatism at ~750 to 730 Ma. The emplacement of kimberlites globally has recently been linked to supercontinent reorganisation and we propose a similar scenario for these Finnish occurrences which, at the time of kimberlite emplacement, were situated on the Baltica paleo-continent. This land mass was contiguous with Laurentia in the Proterozoic and together formed part of Rodinia. The breakup of Rodinia is considered to have commenced at ~750 Ma and initiation of the opening of the Iapetus ocean at ~615 Ma. Contemporaneous with Kaavi-Kuopio magmatism, this latter period of Neoproterozoic crustal extension also includes the emplacement of kimberlites and related rocks in areas that were linked with Baltica as part of Rodinia - West Greenland and eastern North America. Both the initial and final periods of Rodinia’s breakup have been linked to mantle upwellings from the core-mantle boundary. We suggest that kimberlite magmatism in Finland was promoted by the influx of heat from mantle upwellings and lithospheric extension associated with the demise of Rodinia. Although both magmatic episodes are potentially linked to the breakup of Rodinia, whole-rock and perovskite radiogenic isotope compositions for the Kuusamo kimberlites (?Nd(i) +2.6 to +3.3, ?Hf(i) +3.1 to +5.6) are distinct from the Kaavi-Kuopio kimberlites (?Nd(i) -0.7 to +1.8, ?Hf(i) -6.1 to +5.2). The spread in Hf isotope compositions for the Kaavi-Kuopio magmas may be linked to variable assimilation of diverse mantle lithologies.
DS202204-0521
2022
Hergt, J.Guiliani, A., Drysdale, R.N., Woodhead, J.D., Planavsky, N.J., Phillips, D., Hergt, J., Griffin, W.L., Oesch, S., Dalton, H., Davies, G.R.Pertubation of the deep-Earth carbon cycle in response to the Cambrian explosion.Science Advances, doi.10.1126/sciadv.abj1325 1p. PdfMantlesubduction

Abstract: Earth’s carbon cycle is strongly influenced by subduction of sedimentary material into the mantle. The composition of the sedimentary subduction flux has changed considerably over Earth’s history, but the impact of these changes on the mantle carbon cycle is unclear. Here, we show that the carbon isotopes of kimberlite magmas record a fundamental change in their deep-mantle source compositions during the Phanerozoic Eon. The 13C/12C of kimberlites before ~250 Ma preserves typical mantle values, whereas younger kimberlites exhibit lower and more variable ratios-a switch coincident with a recognized surge in kimberlite magmatism. We attribute these changes to increased deep subduction of organic carbon with low 13C/12C following the Cambrian Explosion when organic carbon deposition in marine sediments increased significantly. These observations demonstrate that biogeochemical processes at Earth’s surface have a profound influence on the deep mantle, revealing an integral link between the deep and shallow carbon cycles.
DS1991-0687
1991
Hergt, J.M.Hawkesworth, C.J., Hergt, J.M., Ellam, R.M., McDermott, F.Element fluxes associated with subduction related magmatismPhil. Transactions R. Soc. London, Sect. A., Vol. 335, pp. 393-405GlobalGeochemistry -rare earths, Isotopes
DS1991-0688
1991
Hergt, J.M.Hawkesworth, C.J., Hergt, J.M., McDermott, F., Ellam, R.M.Destructive margin magmatism and the contributions from the mantle wEdge and subducted crustAustralian Journal of Earth Sciences, Vol. 38, December pp. 577-594AustraliaMantle, Subduction
DS1992-0161
1992
Hergt, J.M.Brewer, T.S., Hergt, J.M., Hawkesworth, C.J., et al.Coats Land dolerites and the generation of Antarctic continental floodbasaltsGeological Society Special Publication Magmatism and the causes of the continental, No. 68, pp. 185-208AntarcticaBasalts, Geochemistry, signatures
DS1992-1285
1992
Hergt, J.M.Rock, N.M.S., Griffin, B.J., Edgar, A.D., Paul, D.K., Hergt, J.M.A spectrum of potentially Diamondiferous lamproites and minettes from the Jharia coalfield eastern IndiaJournal of Volcanology and Geothermal Research, Vol. 50, No. 1/2, April 15, pp. 55-84IndiaLamproites, Jharia coalfield
DS1993-0644
1993
Hergt, J.M.Hawkesworth, C.J., Gallagher, K., Hergt, J.M., McDermott, F.Trace element fractionation processes in the generation of island arcbasaltsRoyal Society Transactions, Physical Sciences, Ser. A, Vol. 342, No. 1663, January 15, pp. 179-191MantleSubduction, Magmas
DS1993-0645
1993
Hergt, J.M.Hawkesworth, K., Gallagher, K., Hergt, J.M., McDermott, F.Mantle and slab contribution in arc magmasAnnual Review of Earth and Planetary Sciences, Vol. 21, pp. 175-204MantleSubduction, Tectonics
DS1994-0745
1994
Hergt, J.M.Hawkesworth, C.J., Gallagher, K., Hergt, J.M., McDermottDestructive plate margin magmatism: geochemistry and melt generationLithos, Vol. 33, No. 1-3, October pp. 169-188.MantleGeotectonics, geodynamics, Geochemistry
DS1994-0765
1994
Hergt, J.M.Hergt, J.M., Storey, M., Marriner, G., Tarney, J.Trace element and isotopic compositions of the picritic rocks from CuracaoIsland.International Symposium Upper Mantle, Aug. 14-19, 1994, pp. 94-96.GlobalGeochemistry, Picrites
DS2001-1251
2001
Hergt, J.M.Woodhead, J.D., Hergt, J.M., Davidson, J.P., Eggins, S.Hafnium isotope evidence for conservative element mobility during subduction zone processes.Earth and Planetary Science Letters, Vol. 192, No. 3, pp. 331-46.MantleGeochronology, Subduction
DS200512-0829
2005
Hergt, J.M.Paul, B., Hergt, J.M., Woodhead, J.D.Mantle heterogeneity beneath the Cenozoic volcanic provinces of central Victoria inferred from trace element and Sr Nd Pb and Hf isotope data.Australian Journal of Earth Sciences, Vol. 52, 2, pp. 243-260.Australia, VictoriaGeochronology
DS200612-0568
2006
Hergt, J.M.Hergt, J.M., De Leon, A., Woodhead, J.D.The NSW leucitites: lithospheric melts or hot spot magmas?Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 247. abstract only.Australia, New South WalesLeucitites
DS200612-0684
2006
Hergt, J.M.Kemp, A.J.S., Hawkesworth, C.J., Paterson, B.A., Foster, G.L., Woodhead, J.D., Hergt, J.M., Wormald, R.J.The case of crust mantle interaction during silicic magma genesis: the zircon testimony.Geochimica et Cosmochimica Acta, Vol. 70, 18, 1, p. 12, abstract only.MantleMagmatism
DS200612-1048
2006
Hergt, J.M.Paton, C., Hergt, J.M., Woodhead, J.D., Phillips, D.Laser ablation analysis of DR isotopes in kimberlitic perovskite.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 10. abstract only.AustraliaGeochronology
DS200712-0818
2007
Hergt, J.M.Paton, C., Hergt, J.M., Phillips, D., Woodhead, J.D., Shee, S.R.New insights into the genesis of Indian kimberlites from the Dharwat Craton via in situ SR isotope analysis of groundmass perovskite.Geology, Vol. 35, 11, pp. 1011-1014.IndiaGeochronology
DS200812-0859
2008
Hergt, J.M.Paton, C., Hergt, J.M., Phillips, D., Woodhead, J.D., Shee, S.R.Identifying the asthenospheric component of kimberlite magmas from the Dharwar craton, India.9IKC.com, 3p. extended abstractIndiaDeposit - Narayanpet, Wajakarur
DS200812-0860
2007
Hergt, J.M.Paton, C., Woodhead, J.D., Hergt, J.M., Philipps, D.,Shee, S.Strontium isotope analysis of kimberlitic groundmass perovskite via La-MC-ICP-MS.Geostandards and Geoanalytical Research, in press availableTechnologyGeochronology
DS200812-1265
2008
Hergt, J.M.Woodhead, J.D., Phillips, D., Hergt, J.M., Paton, C.African kimberlites revisited: in situ Sr isotope analysis of groundmass perovskite.9IKC.com, 2p. extended abstractAfrica, South AfricaGroup I and II
DS200912-0573
2009
Hergt, J.M.Paton, C., Hergt, J.M., Woodhead, J.D., Phillips, D., Shee, S.R.Identifying the asthenosphere component of kimberlite magmas from the Dharwar Craton, India.Lithos, in press availableIndiaChemistry
DS2001-0473
2001
Heritage, G.L.Heritage, G.L., Broadhurst, L.J., Birkhead, A.L.The influence of contemporary flow regime on the geomorphology of the Sabie River, South Africa.Geomorphology, Vol. 38, No. 3-4, pp. 197-211.South AfricaAlluvial - river system
DS1860-0050
1867
Heritte, E.Heritte, E.The Diamond and Precious StonesCape Town: Saul Solomon., 32P.Africa, South Africa, Cape ProvinceGemology
DS201610-1879
2016
Herman, F.King, G.E., Guralnik, B., Valla, P.G., Herman, F.Trapped charge thermochronometry and thermometry: a status review.Chemical Geology, in press available 15p.TechnologyThermometry

Abstract: Trapped-charge dating methods including luminescence and electron spin resonance dating have high potential as low temperature (< 100 °C) thermochronometers. Despite an early proof of concept almost 60 years ago, it is only in the past two decades that thermoluminescence (TL), electron-spin-resonance (ESR), and optically stimulated luminescence (OSL), have begun to gain momentum in geological thermochronometry and thermometry applications. Here we review the physics of trapped-charge dating, the studies that led to its development and its first applications for deriving palaeo-temperatures and/or continuous cooling histories. Analytical protocols, which enable the derivation of sample specific kinetic parameters over laboratory timescales, are also described. The key limitation of trapped-charge thermochronometry is signal saturation, which sets an upper limit of its application to < 1 Ma, thus restricting it to rapidly exhuming terrains (> 200 °C Ma? 1), or elevated-temperature underground settings (> 30 °C). Despite this limitation, trapped-charge thermochronometry comprises a diverse suite of versatile methods, and we explore potential future applications and research directions.
DS201212-0599
2012
Herman, J.Rosenthall, A., Yaxley, G.M., Green, D.H., Kovacs, I., Herman, J., Spandler, C.S., Mernagh, T.P.Phase and melting relations of a residue eclogite/pyroxenite within an upwelling heterogeneous upper mantle.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractMantleMelting
DS1986-0360
1986
Herman, J.D.Herman, J.D., Waites, J.E.Surface expression of subsurface structures in the Michigan basinRemote Sensing for Exploration Geology, Fifth Thematic Conf, p. 64. (abstract.) Held Sept. 29, -Oct. 2Michigan, MidcontinentStructure, Tectonics
DS1995-2056
1995
Herman, J.S.White, W.B., Culver, D.C., Herman, J.S., Kane, T.C.Karst lands...earth's land area is dominated by dissolution rather thanerosion..American Scientist, Vol. 83, No. 5, Sept. Oct. pp. 450-459GlobalGeomorphology, Karst topography
DS201212-0023
2012
Herman, L.Armstrong, J.P., Fitzgerald, C., Kjarsgaard, B.A., Herman, L., Tappe, S.Kimberlites of the Coronation Gulf field, northern Slave Craton, Nunavut, Canada.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, NunavutDeposit - 26 kimberlites by name
DS200912-0721
2009
Herman, L.M.Spengler, D., Brueckner, H.K., Herman, L.M., Van Roermund, Drury, MasonLong lived, cold burial of Baltica to 200 km depth.Earth and Planetary Science Letters, Vol. 281, 1-2, April 30, pp. 27-35.Europe, Baltic ShieldSubduction
DS201212-0295
2012
Herman, L.M.Herman, L.M., Grutter, H.S., Pell, J., Holmes, P., Grenon, H.U-Pb geochronology , SR and ND isotope compositions of groundmass perovskite from the Chidliak and Qilaq kimberlites, Baffin Island, Nunavut.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Nunavut, Baffin IslandDeposit - Chidliak, Qilaq
DS1940-0178
1948
Hermann, F.Hermann, F.DiamantenWien: Donau-verlag, 135P.India, Brazil, South AfricaBlank
DS1993-0655
1993
Hermann, G.Hermann, G., Silferstolpe, A.Namibian mining industry - role and prospectsRaw Materials Report, Vol. 9, No. 4, pp. 2-19.NamibiaMining Industry, Economics
DS1993-0656
1993
Hermann, G.Hermann, G., Siuferstolpe, A.Namibian mining industry -role and prospectsRaw Materials Report, Vol. 9, No. 4, pp. 2-19NamibiaCountry profile, Mining industry
DS1995-1662
1995
Hermann, J.Scambelluri, M., Muntener, O., Hermann, J., Piccardo, et al.Subduction of water into mantle: history of an Alpine peridotiteGeology, Vol. 23, No. 5, May pp. 459-462.GlobalSubduction, Peridotite
DS2000-0408
2000
Hermann, J.Hermann, J., Muntener, O., Scambelluri, M.The importance of serpentinite mylonites for subduction and exhumation of oceanic crust.Tectonophysics, Vol. 327, No. 3-4, Dec.15, pp. 225-38.MantleSubduction
DS2001-0474
2001
Hermann, J.Hermann, J., Green, D.H.Experimental constraints on high pressure melting in subducted crustEarth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.149-68.Mantleultra high pressure (UHP), Subduction
DS2001-0475
2001
Hermann, J.Hermann, J., Muntener, O., Gunther, D.Differentiation of mafic magma in a continental crust to mantle transitionzone.Journal of Petrology, Vol. 42, No. 1, Jan. pp. 189-206.MantleMagmatism
DS2001-0476
2001
Hermann, J.Hermann, J., Rubatto, D., Korsakov, A., Shatsky, V.S.Multiple zircon growth during fast exhumation of Diamondiferous deeply subducted continental crust.Contributions to Mineralogy and Petrology, Vol. 141, No. 1, pp. 66-82.Russia, Kazakhstanultra high pressure (UHP), Kokchetav Massif
DS2001-0988
2001
Hermann, J.Rubatto, D., Hermann, J.Exhumation as fast as subduction?Geology, Vol. 29, No. 1, Jan. pp. 3-6.Alpsultra high pressure (UHP), metamorphism, titanite
DS2002-0707
2002
Hermann, J.Hermann, J.Experimental constraints on phase relations in subducted continental crustContribution to Mineralogy and Petrology, Vol.143,pp.219-35., Vol.143,pp.219-35.GlobalUHP - experimental petrology, Subduction zones
DS2002-0708
2002
Hermann, J.Hermann, J.Experimental constraints on phase relations in subducted continental crustContribution to Mineralogy and Petrology, Vol.143,pp.219-35., Vol.143,pp.219-35.GlobalUHP - experimental petrology, Subduction zones
DS2002-1663
2002
Hermann, J.Vesare, B., Rubatto, D., Hermann, J., Barzi, L.Evidence for Late Carboniferous subduction type magmatism in mafic ultramafic cumulates of southwest Tauren..Contributions to Mineralogy and Petrology, Vol. 142, No. 4, pp. 449-64.Europe, AlpsMagmatism - window
DS2003-0578
2003
Hermann, J.Hermann, J.Experimental evidence for diamond facies metamorphism in the Dora Maira MassifLithos, Vol. 70, 3-4, pp. 163-182.ItalyMetamorphism, eclogites
DS2003-1193
2003
Hermann, J.Rubatto, D., Hermann, J.Zircon formation during fluid circulation in eclogites ( Monviso, western Alps):Geochimica et Cosmochimica Acta, Vol. 67, 12, pp. 2173-87.EuropeBlank
DS200412-0819
2003
Hermann, J.Hermann, J.Experimental evidence for diamond facies metamorphism in the Dora Maira Massif.Lithos, Vol. 70, 3-4, pp. 163-182.Europe, ItalyMetamorphism, eclogites
DS200412-1697
2003
Hermann, J.Rubatto, D., Hermann, J.Zircon formation during fluid circulation in eclogites ( Monviso, western Alps): implications for Zr and Hf budget in subductionGeochimica et Cosmochimica Acta, Vol. 67, 12, pp. 2173-87.EuropeSubduction - not specific to diamonds
DS200412-1884
2004
Hermann, J.Spandler,C., Hermann, J., Arculus, R., Mavrogenes, J.Geochemical heterogeneity and element mobility in deeply subducted oceanic crust; insights from high-pressure mafic rocks from NChemical Geology, Vol. 206, 1-2, May 28, pp. 21-42.New CaledoniaSubduction, geochemistry, eclogite
DS200512-0423
2005
Hermann, J.Hermann, J., O'Neill, H.S.C., Berry, A.J.Titanium solubility in olivine in the system TiO2 MgO SiO2: no evidence for an ultra deep origin of Ti bearing olivine.Contributions to Mineralogy and Petrology, Vol. 148, 6, pp. 746-760.UHP
DS200612-0132
2005
Hermann, J.Berry, A.J., Hermann, J., O'Neill, H.S.C., Foran, G.J.Fingerprinting the water site in mantle olivine.Geology, Vol. 33, 11, Nov., pp. 869-872.MantleSpectroscopy, anhydrous minerals
DS200612-0569
2006
Hermann, J.Hermann, J.Experiments and eclogites: constraints on element recycling in subducted crust.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 247. abstract only.MantleSubduction
DS200612-0570
2006
Hermann, J.Hermann, J., Manning, C.Deep fluid release from the slab.Goldschmidt Conference 16th. Annual, S6-02 theme abstract 1/8p. goldschmidt2006.orgMantleMelting
DS200612-0571
2006
Hermann, J.Hermann, J., Rubatto, D., Korsakov, A.V., Shatsky, V.S.The age of metamorphism of Diamondiferous rocks determined with SHRIMP dating of zircons. KokchetavRussian Geology and Geophysics, Vol. 47, 4, pp. 511-518.Russia, KazakhstanUHP - geochronology
DS200612-0735
2005
Hermann, J.Korsakov, A.V., Hermann, J.Silicate and carbonate melt inclusions associated with diamonds in deeply subducted carbonate rocks.Earth and Planetary Science Letters, Vol. 241, 1-2, pp. 104-118.Russia, KazakhstanUHP, Kokchetav massif
DS200612-0741
2006
Hermann, J.Kovasc, I., Hermann, J., O'Neill, H.St.C.Water solubility in forsterite and enstatite: implications for the secular evolution of mantle convection.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 31. abstract only.MantleConvection
DS200612-0854
2006
Hermann, J.Malaspina, N., Hermann, J., Scambelluri, M., Compagnoni, R.Multistage metasomatism in ultrahigh pressure mafic rocks from North Dabie complex (China).Lithos, Vol.90, 1-2, August pp. 19-42.ChinaUHP - metasomatism
DS200612-1227
2006
Hermann, J.Satish-Kumar, M., Hermann, J., Miyamoto, T., Osanai, Y.Fingerprinting fluid processes in the continental crust: an integrated approach using grain scale Sr, C, O isotopes and REE geochemistry.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 557, abstract only.MantleGeochronology
DS200612-1231
2006
Hermann, J.Scambelluri, M., Hermann, J., Malaspina, N.The deep subduction fluids in high and ultrahigh pressure rocks and their interaction with the overlying mantle wedge.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 559, abstract only.MantleUHP, subduction
DS200612-1340
2006
Hermann, J.Spandler, C., Hermann, J.High pressure veins in eclogite from New Caledonia and their significance for fluid migration in subduction zones.Lithos, Vol. 89, 1-2, June pp. 135-153.Asia, New CaledoniaGeochemistry, Pouebo Eclogite Melange, subduction
DS200712-0399
2007
Hermann, J.Hack, A.C., Hermann, J., Mavrogenes, J.A.Mineral solubility and hydrous melting relations in the deep earth: analysis of some binary A-H2O system pressure-temperature composition topologies.American Journal of Science, Vol. 307, 5, pp. 833-855.MantleMelting - water
DS200712-0674
2006
Hermann, J.Malaspina, N., Hermann, J., Scambelluri, M., Compagnoni, R.Polyphase inclusions in garnet orthopyroxenite (Dabie Shan, China) as monitors for metasomatism and fluid related trace element transfer in subduction zone.Geochimica et Cosmochimica Acta, In press availableChinaPeridotite, Maowu ultramafic complex, metasomatism
DS200712-0910
2007
Hermann, J.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S.Phase and melting relations of a residual garnet clinopyroxenite.Plates, Plumes, and Paradigms, 1p. abstract p. A851.MantleMelting
DS200712-0917
2007
Hermann, J.Rubatto, D., Hermann, J.Experimental zircon/melt and zircon/garnet trace element partitioning and implications for the geochronology of crustal rocks.Chemical Geology, Vol. 241, 1-2, June 30, pp. 38-61.TechnologyGeochronology
DS200712-0918
2007
Hermann, J.Rubatto, D., Hermann, J.Zircon behaviour in deeply subducted rocks.Elements, Vol. 3, 1, Feb. pp.31-36.TechnologyUHP - Zircon geochronology
DS200812-0972
2008
Hermann, J.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S.Melting of residual eclogites with variable proportions of quartz coesite.Goldschmidt Conference 2008, Abstract p.A806.TechnologyMagma genesis
DS201012-0638
2010
Hermann, J.Rosenthal, A., Yaxley, G.M., Green, D.H., Hermann, J., Spandler, C.S., Kovacs, I., Mernagh, T.P.Phase and melting relations of a residual eclogite within an upwelling heterogeneous upper mantle.International Mineralogical Association meeting August Budapest, abstract p. 156.MantlePetrogenesis
DS201012-0742
2010
Hermann, J.Spandler, C., Petke, T., Hermann, J.Experimental and natural constraints on the composition of UHP metamorphic fluids. Keynote paper.Goldschmidt 2010 abstracts, abstractTechnologyReview - UHP
DS201212-0358
2012
Hermann, J.Kiseeva, E.S., Yaxley, G.M., Hermann, J., Litasov, K.D., Rosenthal, A., Kamenetsky, V.S.An experimental study of carbonated eclogite at 3 - 5-5 GPA - implications for silicate and carbonate metasomatism in the cratonic mantle.Journal of Petrology, Vol. 53, pp. 727-759.MantleMetasomatism
DS201212-0379
2012
Hermann, J.Kovacs, I., Green, D.H., Rosenthal, A., Hermann, J., St.O'Neill, H., Hibberson, W.O., Udvardi, B.An experimental study of water in nominally anhydrous minerals in the upper mantle near the water saturated solidus.Journal of Petrology, Vol. 53, 10, pp. 2067-2093.MantleWater content
DS201312-0379
2013
Hermann, J.Hermann, J., Zheng, Y-F., Rubatto, D.Deep fluids in subducted continental crust.Elements, Vol. 9, 4, pp. 281-288.MantleSubduction
DS201312-0938
2013
Hermann, J.Vasilyev, V., Yaxley, G., Hermann, J., O'Neill, H.Phase relations of carbonate eclogite during subduction and the effect of redox conditions on diamond - carbonate reactions.Goldschmidt 2013, 1p. AbstractTechnologyEclogite
DS201412-0885
2014
Hermann, J.Stepanov, A.S., Hermann, J., Korsakov, A.V., Rubatto, D.Geochemistry of ultrahigh pressure anatexis: fractionation of elements in the Kokchetav gneisses during melting at diamond facies conditions.Contributions to Mineralogy and Petrology, Vol. 67, 25p.RussiaUHP
DS201412-0944
2014
Hermann, J.Vasilyev, P., Yaxley, G., Hermann, J., O'Neill, H., Berry, A.Experimental investigation of the effect of oxygen fugacity on diamond versus carbonate in carbon-bearing eclogites during deep subduction.Goldschmidt Conference 2014, 1p. AbstractMantleSubduction
DS201510-1798
2015
Hermann, J.Pirard, C., Hermann, J.Focused fluid transfer through the mantle above subduction zones.Geology, Vol. 43, 10, pp. 915-918.MantleSubduction

Abstract: Volcanic arcs above subduction zones are enriched in volatiles and fluid-mobile elements with respect to mid-oceanic ridge basalts. There is general consensus that this particular subduction zone signature is generated by fluid-induced extraction of these elements from subducted oceanic crust and its sedimentary cover. However, how these fluids are transferred through the mantle wedge to the locus of partial melting and what modification the fluids will experience is unresolved. Here we investigate the interaction of slab fluids with the mantle wedge through a series of high-pressure experiments. We explore two end-member processes of focused and porous reactive flow of hydrous slab melts through the mantle. Transfer by porous flow leads to the formation of hydrous minerals that sequester fluid-mobile elements and residual fluids characterized by trace element patterns inconsistent with typical arc lavas. In contrast, no hydrous minerals are formed in the reaction zone of experiments mimicking focused flow, and the typical trace element signature acquired during fluid extraction from the slab is preserved, indicating that this is an efficient process for element transfer through the mantle wedge.
DS201605-0905
2016
Hermann, J.Stepanov, A.S., Rubatto, D., Hermann, J., Korsakov, A.V.Contrasting P-T paths within the Barchi-Kol terrain ( Kokchetav Complex): implications for subduction and exhumation of continental crust.American Mineralogist, Vol. 101, pp. 788-807.RussiaUHP - subduction

Abstract: The Barchi-Kol terrain is a classic locality of ultrahigh-pressure (UHP) metamorphism within the Kokchetav metamorphic belt. We provide a detailed and systematic characterization of four metasedimentary samples using dominant mineral assemblages, mineral inclusions in zircon and monazite, garnet zonation with respect to major and trace elements, and Zr-in-rutile and Ti-in-zircon temperatures. A typical diamond-bearing gneiss records peak conditions of 49 ± 4 kbar and 950-1000 °C. Near isothermal decompression of this rock resulted in the breakdown of phengite associated with a pervasive recrystallization of the rock. The same terrain also contains mica schists that experienced peak conditions close to those of the diamond-bearing rocks, but they were exhumed along a cooler path where phengite remained stable. In these rocks, major and trace element zoning in garnet has been completely equilibrated. A layered gneiss was metamorphosed at UHP conditions in the coesite field, but did not reach diamond-facies conditions (peak conditions: 30 kbar and 800-900 °C). In this sample, garnet records retrograde zonation in major elements and also retains prograde zoning in trace elements. A garnet-kyanite-micaschist that reached significantly lower pressures (24 ± 2 kbar, 710 ± 20 °C) contains garnet with major and trace element zoning. The diverse garnet zoning in samples that experienced different metamorphic conditions allows to establish that diffusional equilibration of rare earth element in garnet likely occurs at ~900-950 °C. Different metamorphic conditions in the four investigated samples are also documented in zircon trace element zonation and mineral inclusions in zircon and monazite. -Pb geochronology of metamorphic zircon and monazite domains demonstrates that prograde (528-521 Ma), peak (528-522 Ma), and peak to retrograde metamorphism (503-532 Ma) occurred over a relatively short time interval that is indistinguishable from metamorphism of other UHP rocks within the Kokchetav metamorphic belt. Therefore, the assembly of rocks with contrasting P-T trajectories must have occurred in a single subduction-exhumation cycle, providing a snapshot of the thermal structure of a subducted continental margin prior to collision. The rocks were initially buried along a low geothermal gradient. At 20-25 kbar they underwent near isobaric heating of 200 °C, which was followed by continued burial along a low geothermal gradient. Such a step-wise geotherm is in good agreement with predictions from subduction zone thermal models.
DS201611-2144
2016
Hermann, J.Stepanov, A.S., Hermann, J., Rubatto, D., Korsakov, A.V., Danyushevsky, L.V.Melting history of an ultrahigh pressure paragneiss revealed by multiphase solid inclusions in garnet, Kokchetav Massif, Kazakhstan.Journal of Petrology, in press available, 24p.Russia, KazakhstanGarnet inclusions

Abstract: Abundant multiphase solid inclusions (MSI) were found in garnet in an ultrahigh-pressure (UHP) paragneiss from the Kokchetav complex, Kazakhstan. The MSI are composed of mineral associations that include rock-forming and accessory minerals, which crystallized during exhumation. We present experimental and analytical protocols for how such inclusions can be homogenized to glass and analysed for major and trace elements. After homogenization we identified two types of glass. One type is present in garnet porphyroblasts in the melanocratic part of the sample and represents a high-pressure melt formed close to peak conditions of >45 kbar, 1000°C. These inclusions are characterized by high concentrations of light rare earth elements (LREE), Th and U. Extraction of these melts resulted in a pronounced depletion of the Kokchetav gneisses in those elements. Measured partition coefficients of large ion lithophile elements (LILE) between phengite inclusions and melt inclusions are DRb?=?1•9-2•5, DBa?=?1•1-6•9 and DCs?=?0•6-0•8, resulting in limited depletion of these elements during partial melting in the presence of phengite. The Nb concentration in melts (27?ppm) is about double that in the restite (15?ppm), indicating slightly incompatible behaviour during UHP anatexis, despite the presence of residual accessory rutile and phengite. A second type of inclusion occurs in garnet from the leucocratic part of the rock and represents a late-stage melt formed during exhumation at 650-750°C and crustal pressures. These inclusions are characterized by low LREE and Nb and high U. Zircon domains formed during high-temperature melting are characterized by high Ti content (100-300?ppm) and unfractionated Th/U (0•4-0•8), whereas the low-temperature domains display low Ti (10?ppm) and Th/U (0•08). The composition of UHP melts with moderate enrichment in LILE, no depletion in Nb and extreme enrichment in LREE and Th is remarkably different from the trace element signature of arc basalts, arguing against involvement of this type of melting in the generation of arc crust. The composition of the UHP melt inclusions is similar to that of melt inclusions from HP crustal xenoliths from Pamir and also to some shoshonites from Tibet. UHP anatexis, as observed in the Kokchetav massif, might be related to the formation of shoshonitic alkaline igneous rocks, which are common in collisional settings.
DS201712-2696
2018
Hermann, J.Jollands, M.C., Hanger, B.J., Yaxley, G.M., Hermann, J., Kilburn, M.R.Timescales between mantle metasomatism and kimberlite ascent indicated by diffusion profiles in garnet crystals from periodotite xenoliths.Earth and Planetary Science Letters, Vol. 481, pp. 143-153.Africa, South Africadeposit - Wesselton

Abstract: Rare garnet crystals from a peridotite xenolith from the Wesselton kimberlite, South Africa, have distinct zones related to two separate episodes of mantle metasomatism. The garnet cores were firstly depleted through melt extraction, then equilibrated during metasomatism by a potentially diamond-forming carbonate-bearing or proto-kimberlitic fluid at 1100-1300?°C and 4.5-5.5 GPa. The garnet rim chemistry, in contrast, is consistent with later overgrowth in equilibrium with a kimberlite at around and . This suggests that the rock was physically moved upwards by up to tens of kilometres between the two metasomatic episodes. Preserved high Ca, Al and Cr contents in orthopyroxenes suggest this uplift was tectonic, rather than magmatic. Diffusion profiles were measured over the transitions between garnet cores and rims using electron microprobe (Mg, Ca, Fe for modelling, plus Cr, Mn, Ti, Na, Al) and nano Secondary Ion Mass Spectrometry (NanoSIMS; 89Y, along with 23Na, Ca, Cr, Fe, Mn and Ti) analyses. The short profile lengths (generally <10 ?m) and low Y concentrations (0.2-60 ppm) make the NanoSIMS approach preferable. Diffusion profiles at the interface between the zones yield constraints on the timescale between the second metasomatic event and eruption of the kimberlite magma that brought the xenolith to the surface. The time taken to form the diffusion profiles is on the order of 25 days to 400 yr, primarily based on modelling of Y diffusion along with Ca, Fe and Mg (multicomponent diffusion) profiles. These timescales are too long to be produced by the interaction of the mantle xenolith with the host kimberlite magma during a single-stage ascent to the crust (hours to days). The samples offer a rare opportunity to study metasomatic processes associated with failed eruption attempts in the cratonic lithosphere.
DS201808-1755
2018
Hermann, J.Jollands, M.C., Hanger, B.J., Yaxley, G.M., Hermann, J., Kilburn, M.R.Timescales between mantle metasomatism and kimberlite ascent indicated by diffusion profiles in garnet crystals from peridotite xenoliths.Earth and Planetary Science Letters, Vol. 481, 1, pp. 143-153.Mantlekimberlite

Abstract: Rare garnet crystals from a peridotite xenolith from the Wesselton kimberlite, South Africa, have distinct zones related to two separate episodes of mantle metasomatism. The garnet cores were firstly depleted through melt extraction, then equilibrated during metasomatism by a potentially diamond-forming carbonate-bearing or proto-kimberlitic fluid at 1100-1300?°C and 4.5-5.5 GPa. The garnet rim chemistry, in contrast, is consistent with later overgrowth in equilibrium with a kimberlite at around and . This suggests that the rock was physically moved upwards by up to tens of kilometres between the two metasomatic episodes. Preserved high Ca, Al and Cr contents in orthopyroxenes suggest this uplift was tectonic, rather than magmatic. Diffusion profiles were measured over the transitions between garnet cores and rims using electron microprobe (Mg, Ca, Fe for modelling, plus Cr, Mn, Ti, Na, Al) and nano Secondary Ion Mass Spectrometry (NanoSIMS; 89Y, along with 23Na, Ca, Cr, Fe, Mn and Ti) analyses. The short profile lengths (generally <10 ?m) and low Y concentrations (0.2-60 ppm) make the NanoSIMS approach preferable. Diffusion profiles at the interface between the zones yield constraints on the timescale between the second metasomatic event and eruption of the kimberlite magma that brought the xenolith to the surface. The time taken to form the diffusion profiles is on the order of 25 days to 400 yr, primarily based on modelling of Y diffusion along with Ca, Fe and Mg (multicomponent diffusion) profiles. These timescales are too long to be produced by the interaction of the mantle xenolith with the host kimberlite magma during a single-stage ascent to the crust (hours to days). The samples offer a rare opportunity to study metasomatic processes associated with failed eruption attempts in the cratonic lithosphere.
DS201809-2048
2018
Hermann, J.Kempf, E.D., Hermann, J.Hydrogen in corporation and retention in metamorphic olivine during subduction: implications for the deep water cycle.Geology, Vol. 46, 6, pp. 571-574.Mantlewater

Abstract: Incorporation of hydrogen into metamorphic olivine during dehydration reactions in the subducting oceanic lithosphere provides a mechanism to replenish the deep mantle with water. Fourier transform infrared spectroscopy of metamorphic olivines formed at 2.5 GPa and 550 °C through the reaction antigorite + brucite = olivine + chlorite + water shows water contents between 100 and 140 ppm H2O associated exclusively with silicon vacancies, similar to the highest values found in peridotite xenoliths. Brucite involvement in the olivine-forming reaction ensures H2O saturation and a low Si activity, favoring hydrogen incorporation into Si vacancies. The mapped water distribution in olivine is consistent with growth zoning and there is no evidence of water gain or loss. Thus, even for metamorphic timescales of several million years at 550 °C, no ionic diffusion modification is observed, in agreement with recent experimental findings. Metamorphic olivines formed by this dehydration reaction may contribute considerable amounts of water to the deep water cycle. Additionally, olivine with abundant H in Si vacancies are expected to be rheologically weaker than anyhdrous mantle olivine, and might provide a weak interface between slabs and mantle wedges in subduction zones at conditions beyond the stability of hydrous phases.
DS201810-2374
2018
Hermann, J.Rosenthal, A., Yaxley, G.M., Crichton, W.A., Kovacs, I.J., Spandler, C., Hermann, J., Sandorne, J.K., Rose-Koga, E., Pelleter, A-A.Phase relations and melting of nominally 'dry' residual eclogites with variable CaO/Na2O from 3 to 5 Gpa and 1250 to 1500C; implications for refertilisation of upwelling heterogeneous mantle. Lithos, Vol. 314-315, pp. 506-519.Mantlemelting
DS202009-1614
2020
Hermann, J.Brovarone, A.V., Butch, C.J., Ciappa, A., Cleaves, H.J., Elmaleh, A., Faccenda, M., Feineman, M., Hermann, J., Nestola, F., Cordone, A., Giovannelli., D.Let there be water: how hydration/dehydration reactions accompany key Earth and life processes.American Mineralogist, Vol. 105, pp. 1152-1160. pdfMantlecarbon

Abstract: Water plays a key role in shaping our planet and making life possible. Given the abundance of water on Earth's surface and in its interior, chemical reactions involving water, namely hydration and dehydration reactions, feature prominently in nature and are critical to the complex set of geochemical and biochemical reactions that make our planet unique. This paper highlights some fundamental aspects of hydration and dehydration reactions in the solid Earth, biology, and man-made materials, as well as their connections to carbon cycling on our planet.
DS202108-1288
2021
Hermann, J.Hermann, J., Lakey, S.Water transfer to the deep mantle through hydrous, Al-rich silicates in subduction zones.Geology, Vol. 49, pp. 911-915.Mantlewater

Abstract: Constraining deep-water recycling along subduction zones is a first-order problem to understand how Earth has maintained a hydrosphere over billions of years that created conditions for a habitable planet. The pressure-temperature stability of hydrous phases in conjunction with slab geotherms determines how much H2O leaves the slab or is transported to the deep mantle. Chlorite-rich, metasomatic rocks that form at the slab-mantle interface at 50-100 km depth represent an unaccounted, H2O-rich reservoir in subduction processes. Through a series of high-pressure experiments, we investigated the fate of such chlorite-rich rocks at the most critical conditions for subduction water recycling (5-6.2 GPa, 620-800 °C) using two different natural ultramafic compositions. Up to 5.7 GPa, 740 °C, chlorite breaks down to an anhydrous peridotite assemblage, and H2O is released. However, at higher pressures and lower temperatures, a hydrous Al-rich silicate (11.5 Å phase) is an important carrier to enable water transfer to the deep mantle for cold subduction zones. Based on the new phase diagrams, it is suggested that the deep-water cycle might not be in secular equilibrium.
DS202205-0717
2022
Hermann, J.Sieber, M.J., Yaxley, G.M., Hermann, J.COH-fluid induced metasomatism of peridotites in the forearc mantle.Contributions to Mineralogy and Petrology, Vol. 177, 44, 10.1007/s00410-022-01905-w.Mantleperidotites

Abstract: Devolatilization of subducting lithologies liberates COH-fluids. These may become partially sequestered in peridotites in the slab and the overlying forearc mantle, affecting the cycling of volatiles and fluid mobile elements in subduction zones. Here we assess the magnitudes, timescales and mechanism of channelized injection of COH-fluids doped with Ca2+aq, Sr2+aq and Ba2+aq into the dry forearc mantle by performing piston cylinder experiments between 1-2.5 GPa and 600-700 °C. Cylindrical cores of natural spinel-bearing harzburgites were used as starting materials. Based on mineral assemblage and composition three reaction zones are distinguishable from the rim towards the core of primary olivine and orthopyroxene grains. Zone 1 contains carbonates?+?quartz?±?kyanite and zone 2 contains carbonates?+?talc?±?chlorite. Olivine is further replaced in zone 3 by either antigorite?+?magnesite or magnesite?+?talc within or above antigorite stability, respectively. Orthopyroxene is replaced in zone 3 by talc?+?chlorite. Mineral assemblages and the compositions of secondary minerals depend on fluid composition and the replaced primary silicate. The extent of alteration depends on fluid CO2 content and fluid/rock-ratio, and is further promoted by fluid permeable reaction zones and reaction driven cracking. Our results show that COH-fluid induced metasomatism of the forearc mantle is self-perpetuating and efficient at sequestering Ca2+aq, Sr2+aq, Ba2+aq and CO2aq into newly formed carbonates. This process is fast with 90% of the available C sequestered and nearly 50% of the initial minerals altered at 650 °C, 2 GPa within 55 h. The dissolution of primary silicates under high COH-fluid/rock-ratios, as in channelized fluid flow, enriches SiO2aq in the fluid, while CO2aq is sequestered into carbonates. In an open system, the remaining CO2-depleted, Si-enriched aqueous fluid may cause Si-metasomatism in the forearc further away from the injection of the COH-fluid into peridotite.
DS1900-0763
1909
Hermann, P.Hermann, P.Beitraege Zur Geologie von Deutsch SuedwestafrikaZeitsch. F. Prakt. Geol., BD. 17, PP. 372-396.Africa, NamibiaGeology, Diamonds
DS1995-0789
1995
Hermann, R.B.Hermann, R.B.Broadband seismology - small regional seismic networks...investigation Of the New Madrid seismic zoneUnited States Geological Survey (USGS) Prof. paper, No. 1538-S, 15p.MidcontinentGeophysics -seismics, New Madrid Zone
DS200912-0610
2009
Hermant, K.Rajaram, M., Anand, S.P., Hermant, K., Purucker, M.E.Currie isotherm map of Indian subcontinent from satellite and aeromagnetic data.Earth and Planetary Science Letters, Vol. 281, 3-4, May 15, pp. 147-158.IndiaGeophysics - magnetics
DS200612-1393
2005
Hermanto, R.Sun, T.T., Wathanakul,P., Atichat, W., Moh, L.H., Kem, L.K., Hermanto, R.Kalimantan diamond: morphology, surface features and some spectroscopic approaches.Australian Gemmologist, Vol. 22, 5, pp. 186-195.Asia, Indonesia, KalimantanDiamond morphology
DS1992-0704
1992
Hermes, O.D.Hermes, O.D., Zartman, R.E.Late Proterozoic and Silurian alkaline plutons within the southeastern New England Avalon ZoneJournal of Geology, Vol. 100, pp. 477-486GlobalAlkaline rocks
DS2001-0658
2001
Hermitte, D.Laverne, C., Agriniet, P., Hermitte, D., Bohn, M.Chemical fluxes during hydrothermal alteration of 1200 m long section of dikes in the oceanic crust Hole 504B.Chemical Geology, Vol. 181,No. 1-4, pp. 73-98.GlobalDike - sheeted, ophiolite, dolerite, Geochemistry
DS2002-0709
2002
Herms, P.Herms, P.Fluids in a 2 Ga old subduction zone - deduced from eclogite facies rocks of the Usagaran belt, Tanzania.European Journal of Mineralogy, Vol. 14,pp.361-73., Vol. 14,pp.361-73.TanzaniaEclogites, Geochonology
DS2002-0710
2002
Herms, P.Herms, P.Fluids in a 2 Ga old subduction zone - deduced from eclogite facies rocks of the Usagaran belt, Tanzania.European Journal of Mineralogy, Vol. 14,pp.361-73., Vol. 14,pp.361-73.TanzaniaEclogites, Geochonology
DS2002-0711
2002
Herms, P.Herms, P.Fluids in a 2Ga old subduction zone - deduced from eclogite facies rocks of the Usagaran belt, Tanzania.European Journal of Mineralogy, Vol.14,2,pp.361-74.TanzaniaSubduction, Eclogites
DS201112-0405
2011
Herms, P.Halama, R., Timm, J., Herms, P., Hauff, F., Schenk, V.A stable ( Li,O) and radiogenic (Sr, Nd) isotope perspective on metasomatic processes in a subducting slab.Chemical Geology, Vol. 281, 3-4, pp. 151-166.MantleSubduction
DS2002-0459
2002
HernadezFinn, C.A., Pilkington, M., Miles, Hernadez, Cuevas, Velez, Sweeney, KucksThe new North American magnetic anomaly mapGeological Society of America Annual Meeting Oct. 27-30, Abstract p. 387.United States, CanadaMap - magnetic
DS2002-1265
2002
Hernadez, J.Pilot, S., Hernadez, J., Villemant, B.Evidence for high silicic melt circulation and metasomatic events in the mantle beneath alkaline provinces: the Na Fe augitic green core pyroxenes...Mineralogy and Petrology, Vol. 76, No. 1-2, pp. 39-62.French Massif CentralTertiary alkali basalts - Cantal Massif
DS200512-0858
2005
Hernadez, J.Pilet, S., Hernadez, J., Sylvester, P., Poujol, M.The metasomatic alternative for ocean island basalt chemical heterogeneity.Earth and Planetary Science Letters, Advanced in press,MantleSubduction, metasomatism
DS201312-0380
2013
Hernandez, E.R.Hernandez, E.R., Alfe, D., Brodholt, J.The in corporation of water into lower mantle perovskites: a first principles study.Earth and Planetary Science Letters, Vol. 364, pp. 37-43.MantlePerovskite
DS1987-0290
1987
Hernandez, J.Hernandez, J., De Larouziere, F.D., Bolze, J., Bordet, P.Neogene magmatism in the Western Mediterranean area, Southern Spain, North Africa- strike slip faulting and calc alkaline volcanism.(in French)Bulletin Soc. Geol. Fr.(in French), Vol. 3, No. 2, pp. 257-267GlobalLamproite, Shoshonite
DS1989-0626
1989
Hernandez, J.Hernandez, J., Mougenot, D.Petrology of a seaward extension of the East African rift in the northern Mozambique continental marginNew Mexico Bureau of Mines Bulletin., Continental Magmatism Abstract Volume, Held, Bulletin. No. 131, p. 128. AbstractGlobalTectonics
DS2002-1264
2002
Hernandez, J.Pilet, S., Hernandez, J., Villemant, B.Evidence for high silicic melt circulation and metasomatic events in the mantle beneath alkaline provinces: the Na Fe augitic green core pyroxenes.Mineralogy and Petrology, Vol. 76, 1-2, pp.39-62.French Massif CentralTertiary alkali basalts
DS200412-1547
2004
Hernandez, J.Pilet, S., Hernandez, J., Sylvester, P.J.Isotopic signature in OIB mantle sources: the metasomatic alternative.Geochimica et Cosmochimica Acta, 13th Goldschmidt Conference held Copenhagen Denmark, Vol. 68, 11 Supp. July, ABSTRACT p.A556.MantleMetasomatism
DS200512-0337
2004
Hernandez, J.Gill, R.C., Aparicio, A., El Azzouzi, M., Hernandez, J., Thirlwall, M.F., Bourgois, J., Marriner, G.F.Depleted arc volcanism in the Alboran Sea and shoshonitic volcanism in Morocco: geochemical and isotopic constraints on Neogene tectonic processes.Lithos, Vol. 78, 4, pp. 363-388.Africa, MoroccoShoshonite
DS201809-2024
2018
Hernandez, J.A.Garber, J.M., Maurya, S., Hernandez, J.A., Duncan, M.S., Zeng, L., Zhang, H.L.Multidisciplanary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.Geochemistry, Geophysics, Geosystems, Vol. 19, 7, pp. 2062-2086. doi.org/10/1029/ 2018GC007534Mantlegeophysics - seismics

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120-150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS202009-1628
2018
Hernandez, J.A.Garber, J.M., Maurya, S., Hernandez, J.A., Duncan, M.S., Zeng, L., Zhang, H.L.Multidisciplenary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.Geochemistry, Geophysics, Geosystems, Vol. 19: https://doi.org/10.1029/2018GC007534Mantleeclogite

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120-150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS201807-1491
2018
Hernandez, J-A.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, Li., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere. Mentions Jericho and Roberts VictorGeochemistry, Geophysics, Geosystems, https://doi.org/10.1029/2018GCC007534Globalthermobarometry

Abstract: Some seismic models derived from tomographic studies indicate elevated shear?wave velocities (?4.7 km/s) around 120?150 km depth in cratonic lithospheric mantle. These velocities are higher than those of cratonic peridotites, even assuming a cold cratonic geotherm (i.e., 35 mW/m2 surface heat flux) and accounting for compositional heterogeneity in cratonic peridotite xenoliths and the effects of anelasticity. We reviewed various geophysical and petrologic constraints on the nature of cratonic roots (seismic velocities, lithology/mineralogy, electrical conductivity, and gravity) and explored a range of permissible rock and mineral assemblages that can explain the high seismic velocities. These constraints suggest that diamond and eclogite are the most likely high?Vs candidates to explain the observed velocities, but matching the high shear?wave velocities requires either a large proportion of eclogite (>50 vol.%) or the presence of up to 3 vol.% diamond, with the exact values depending on peridotite and eclogite compositions and the geotherm. Both of these estimates are higher than predicted by observations made on natural samples from kimberlites. However, a combination of ?20 vol.% eclogite and ~2 vol.% diamond may account for high shear?wave velocities, in proportions consistent with multiple geophysical observables, data from natural samples, and within mass balance constraints for global carbon. Our results further show that cratonic thermal structure need not be significantly cooler than determined from xenolith thermobarometry.
DS201808-1745
2018
Hernandez, J-A.Garber, J.M., Maurya, S., Hernandez, J-A., Duncan, M.S., Zeng, L., Zhang, H.L., Faul, U., McCammon, C., Montagner, J-P., Moresi, L., Romanowicz, B.A., Rudnick, R.L., Stixrude, L.Multidisciplinary constraints on the abundance of diamond and eclogite in the cratonic lithosphere.G3 Geochemistry, Geophysics, Geosystems, http:/orchid.org/0000-0001-5313-0982Mantleeclogite
DS2001-0011
2001
Hernandez-Pacheco, A.Ahijado, A., Casillas, R., Hernandez-Pacheco, A.The dike swarms of the Amanay Massif, Fuerteventura, Canary Islands (Spain)Journal of African Earth Sciences, Vol. 19, No. 3, Apr. pp.333-46.GlobalAlkaline rocks, Dike Swarms
DS1998-0615
1998
Hernandez-Perez, I.Hernandez-Perez, I., et al.Aeromagnetic map to prove Mexico's mining potentialThe Leading Edge, Aug. pp. 1085-6MexicoGeophysics - magnetics
DS202007-1168
2020
Hernandez-Uribe, D.Palin, R.M., Santosh, M., Cao, W., Li, S-S., Hernandez-Uribe, D.Secular change and the onset of plate tectonics on Earth.Earth Science Reviews, in press available 41p. PdfMantleplate tectonics

Abstract: The Earth as a planetary system has experienced significant change since its formation c. 4.54 Gyr ago. Some of these changes have been gradual, such as secular cooling of the mantle, and some have been abrupt, such as the rapid increase in free oxygen in the atmosphere at the Archean-Proterozoic transition. Many of these changes have directly affected tectonic processes on Earth and are manifest by temporal trends within the sedimentary, igneous, and metamorphic rock record. Indeed, the timing of global onset of mobile-lid (subduction-driven) plate tectonics on our planet remains one of the fundamental points of debate within the geosciences today, and constraining the age and cause of this transition has profound implications for understanding our own planet's long-term evolution, and that for other rocky bodies in our solar system. Interpretations based on various sources of evidence have led different authors to propose a very wide range of ages for the onset of subduction-driven tectonics, which span almost all of Earth history from the Hadean to the Neoproterozoic, with this uncertainty stemming from the varying reliability of different proxies. Here, we review evidence for paleo-subduction preserved within the geological record, with a focus on metamorphic rocks and the geodynamic information that can be derived from them. First, we describe the different types of tectonic/geodynamic regimes that may occur on Earth or any other silicate body, and then review different models for the thermal evolution of the Earth and the geodynamic conditions necessary for plate tectonics to stabilize on a rocky planet. The community's current understanding of the petrology and structure of Archean and Proterozoic oceanic and continental crust is then discussed in comparison with modern-day equivalents, including how and why they differ. We then summarize evidence for the operation of subduction through time, including petrological (metamorphic), tectonic, and geochemical/isotopic data, and the results of petrological and geodynamical modeling. The styles of metamorphism in the Archean are then examined and we discuss how the secular distribution of metamorphic rock types can inform the type of geodynamic regime that operated at any point in time. In conclusion, we argue that most independent observations from the geological record and results of lithospheric-scale geodynamic modeling support a global-scale initiation of plate tectonics no later than c. 3 Ga, just preceding the Archean-Proterozoic transition. Evidence for subduction in Early Archean terranes is likely accounted for by localized occurrences of plume-induced subduction initiation, although these did not develop into a stable, globally connected network of plate boundaries until later in Earth history. Finally, we provide a discussion of major unresolved questions related to this review's theme and provide suggested directions for future research.
DS1950-0068
1951
Herndon, B.Herndon, B.America's Only Diamond MineCollier's., AUG. 25TH., 5P.United States, Gulf Coast, Arkansas, PennsylvaniaPopular Account Of The History Of The Mine
DS200612-0572
2006
Herndon, J.M.Herndon, J.M.Energy for geodynamics: mantle decompression thermal tsunami.Current Science, Vol. 90, 12, pp. 1605-1606.MantleGeodynamics
DS200612-0573
2005
Herndon, J.M.Herndon, J.M.Whole earth decompression dynamics.Current Science, Vol. 89, 11, Dec. pp. 1937-1941.MantleGeodynamics
DS200812-0633
2008
Hernlund, J.Lay, T., Hernlund, J., Buffett, B.A.Core mantle boundary heat flow.Nature Geoscience, Vol. 1, 1, pp. 25-32.MantleGeothermometry
DS201112-0839
2011
Hernlund, J.Rainey, E.S.G., Kavner, A., Hernlund, J.Heat flow in the laser heated diamond anvil cell and the thermal conductivity of the lower mantle.Goldschmidt Conference 2011, abstract p.1689.Mantle3D
DS201312-0381
2013
Hernlund, J.Hernlund, J.Mantle fabric unravelled?Nature Geoscience, Vol. 6, pp. 516-518.MantleFlow patterns, texture
DS201312-0388
2013
Hernlund, J.Hirose, K., Labrosse, S., Hernlund, J.Composition and state of the core.Annual Review of Earth and Planetary Sciences, Vol. 41, pp. 657-691.MantleMineralogy
DS201412-0024
2014
Hernlund, J.Asimow, P., Hernlund, J., Karki, B.Melting and melt properties in the deep Earth.Goldschmidt Conference 2014, 1p. AbstractMantleMelting
DS202106-0973
2021
Hernlund, J.Tagawa, S., Sakamoto, N., Hirose, K., Hernlund, J., Ohishi, Y., Yurimoto, H.Experimental evidence for more hydrogen in Earth's core than in the oceans.Nature Communications, doi.org/10.1038/s41467-021-22035-0 Vol. 12 8p. PdfMantlehydrogen

Abstract: Hydrogen is one of the possible alloying elements in the Earth’s core, but its siderophile (iron-loving) nature is debated. Here we experimentally examined the partitioning of hydrogen between molten iron and silicate melt at 30-60 gigapascals and 3100-4600?kelvin. We find that hydrogen has a metal/silicate partition coefficient DH???29 and is therefore strongly siderophile at conditions of core formation. Unless water was delivered only in the final stage of accretion, core formation scenarios suggest that 0.3-0.6?wt% H was incorporated into the core, leaving a relatively small residual H2O concentration in silicates. This amount of H explains 30-60% of the density deficit and sound velocity excess of the outer core relative to pure iron. Our results also suggest that hydrogen may be an important constituent in the metallic cores of any terrestrial planet or moon having a mass in excess of ~10% of the Earth.
DS200512-0424
2005
Hernlund, J.W.Hernlund, J.W., Thomas, C., Tackley, P.J.A doubling of the post perovskite phase boundary and structure of the Earth's lowermost mantle.Nature, no. 7035, pp. 882-885.MantlePerovskite
DS200612-1405
2005
Hernlund, J.W.Tackley, P.J., Xie, S., Nakagawa, T., Hernlund, J.W.Numerical and laboratory studies of mantle convection: philosphy, accomplishments and thermochemical structure and evolution.American Geophysical Union, Geophysical Monograph, Ed. Van der Hilst, Earth's Deep Mantle, structure ...., No. 160, pp. 83-100.MantleConvection
DS200712-0429
2007
Hernlund, J.W.Hernlund, J.W., Labrosse, S., Coltice, N.The energy balance at the core-mantle boundary.Plates, Plumes, and Paradigms, 1p. abstract p. A399.MantleGeothermometry
DS200712-0430
2007
Hernlund, J.W.Hernlund, J.W., Tackley, P.J.Some dynamical consequences of partial melting in Earth's deep mantle.Physics of the Earth and Planetary Interiors, Vol. 162, 1-2, pp. 149-163.MantleMelting
DS200712-0431
2007
Hernlund, J.W.Hernlund, J.W., Tackley, P.J.Some dynamical consequences of partial melting in Earth's deep mantle.Physics of the Earth and Planetary Interiors, Vol. 162, 1-2, pp. 149-163.MantleMelting
DS200812-0466
2008
Hernlund, J.W.Hernlund, J.W., Houser, C.On the statistical distribution of seismic velocities in Earth's deep mantle.Earth and Planetary Science Letters, Vol. 265, 3-4, Jan. 30, pp. 423-437.MantleGeophysics - seismics
DS200812-0467
2008
Hernlund, J.W.Hernlund, J.W., Stevenson, D.J., Takley, P.J.Bouyant melting instabilities beneath extending lithosphere: 1. numerical models.Journal of Geophysical Research, Vol. 113, B4, B04405MantleMelting
DS200812-0468
2008
Hernlund, J.W.Hernlund, J.W., Stevenson, D.J., Takley, P.J.Bouyant melting instabilities beneath extending lithosphere: 2. linear analysis.Journal of Geophysical Research, Vol. 113, B4, B04406MantleMelting
DS200812-1147
2007
Hernlund, J.W.Tackley, P.J., Nakagawa, T., Hernlund, J.W.Influence of the post perovskite transition on thermal and thermo-chemical mantle convection.AGU American Geophysical Union Monograph, No. 174, pp. 229-248.MantleGeothermometry
DS200912-0297
2008
Hernlund, J.W.Hernlund, J.W., Tackley, P.J.Modelling mantle convection in the spherical annulus.Physics of the Earth and Planetary Interiors, Vol. 171, 1-4, pp. 48-54.MantleConvection
DS201704-0620
2017
Hernlund, J.W.Ballmer, M.D., Houser, C., Hernlund, J.W., Wentzcovitch, R.M., Hirose, K.Persistence of strong silica enriched domains in the Earth's lower mantle.Nature Geoscience, Vol. 10, 3, pp. 236-240.MantleGeophysics - seismic

Abstract: The composition of the lower mantle—comprising 56% of Earth’s volume—remains poorly constrained. Among the major elements, Mg/Si ratios ranging from ~0.9-1.1, such as in rocky Solar-System building blocks (or chondrites), to ~1.2-1.3, such as in upper-mantle rocks (or pyrolite), have been proposed. Geophysical evidence for subducted lithosphere deep in the mantle has been interpreted in terms of efficient mixing, and thus homogenous Mg/Si across most of the mantle. However, previous models did not consider the effects of variable Mg/Si on the viscosity and mixing efficiency of lower-mantle rocks. Here, we use geodynamic models to show that large-scale heterogeneity associated with a 20-fold change in viscosity, such as due to the dominance of intrinsically strong (Mg, Fe)SiO3-bridgmanite in low-Mg/Si domains, is sufficient to prevent efficient mantle mixing, even on large scales. Models predict that intrinsically strong domains stabilize mantle convection patterns, and coherently persist at depths of about 1,000-2,200?km up to the present-day, separated by relatively narrow up-/downwelling conduits of pyrolitic material. The stable manifestation of such bridgmanite-enriched ancient mantle structures (BEAMS) may reconcile the geographical fixity of deep-rooted mantle upwelling centres, and geophysical changes in seismic-tomography patterns, radial viscosity, rising plumes and sinking slabs near 1,000?km depth. Moreover, these ancient structures may provide a reservoir to host primordial geochemical signatures.
DS202101-0015
2020
Hernlund, J.W.Houser, C., Hernlund, J.W., Valencia-Cardona, J., Wentzcovitch, R.M.Discriminating lower mantle composition.Physics of the Earth and Planetary Interiors, Vol. 308, 106552, 14p. PdfMantlegeophysics - seismics

Abstract: Constraining Earth's bulk composition is fundamental to understanding our planet's formation and evolution. While the lower mantle accounts for a majority of the bulk silicate Earth, it is also the least accessible. As experimental and theoretical mineral physics constraints on mineral elasticity at lower mantle temperatures and pressures have improved, comparisons between predicted seismic velocity and density profiles for hypothesized bulk compositions and 1D seismic models have become commonplace. However, the degree to which a given composition is a better or worse fit than another composition is not always reported, nor are the influences of the assumed temperature profile and other uncertainties discussed. Here we compare seismic velocities and densities for perovskitite, pyrolite, and harzburgite bulk compositions calculated using advanced ab initio techniques to explore the extent to which the associated uncertainties affect our ability to distinguish between candidate compositions. We find that predicted differences between model compositions are often smaller than the influence of temperature uncertainties and therefore these comparisons lack discriminatory power. The inability to distinguish between compositions is largely due to the high sensitivity of seismic properties to temperature accompanied by uncertainties in the mantle geotherm, coupled with diminished sensitivity of seismic velocity to composition toward the base of the mantle. An important exception is the spin transition in (Mg,Fe)O-ferropericlase, which is predicted to give a distinct variation in compressional wave velocity that should distinguish between relatively ferro-magnesian and silica-rich compositions. However, the absence of an apparent spin transition signature in global 1D seismic profiles is a significant unresolved issue in geophysics, and it has important geochemical implications. The approach we present here for establishing discriminatory power for such comparisons can be applied to any estimate of seismic velocities and associated uncertainties, and offers a straightforward tool to evaluate the robustness of model comparisons.
DS202102-0199
2021
Hernlund, J.W.Houser, C., Hernlund, J.W., Valencia-Cardona, J., Wentzcovitch, R.M.Discriminating lower mantle composition.Physics of the Earth and Planetary Interiors, Vol. 308, di.org/10.1016 /jpepi.2020. 106552 14p. PdfMantlegeophysics - seismics

Abstract: Constraining Earth's bulk composition is fundamental to understanding our planet's formation and evolution. While the lower mantle accounts for a majority of the bulk silicate Earth, it is also the least accessible. As experimental and theoretical mineral physics constraints on mineral elasticity at lower mantle temperatures and pressures have improved, comparisons between predicted seismic velocity and density profiles for hypothesized bulk compositions and 1D seismic models have become commonplace. However, the degree to which a given composition is a better or worse fit than another composition is not always reported, nor are the influences of the assumed temperature profile and other uncertainties discussed. Here we compare seismic velocities and densities for perovskitite, pyrolite, and harzburgite bulk compositions calculated using advanced ab initio techniques to explore the extent to which the associated uncertainties affect our ability to distinguish between candidate compositions. We find that predicted differences between model compositions are often smaller than the influence of temperature uncertainties and therefore these comparisons lack discriminatory power. The inability to distinguish between compositions is largely due to the high sensitivity of seismic properties to temperature accompanied by uncertainties in the mantle geotherm, coupled with diminished sensitivity of seismic velocity to composition toward the base of the mantle. An important exception is the spin transition in (Mg,Fe)O-ferropericlase, which is predicted to give a distinct variation in compressional wave velocity that should distinguish between relatively ferro-magnesian and silica-rich compositions. However, the absence of an apparent spin transition signature in global 1D seismic profiles is a significant unresolved issue in geophysics, and it has important geochemical implications. The approach we present here for establishing discriminatory power for such comparisons can be applied to any estimate of seismic velocities and associated uncertainties, and offers a straightforward tool to evaluate the robustness of model comparisons.
DS202111-1784
2021
Hernlund, J.W.Shephard, G.E., Houser, C., Hernlund, J.W., Valencia-Cardona, J.J., Tronnes, R.G., Wentzcovitch, R.M.Seismological expression of the iron spin crossover in ferropericlase in the Earth's lower mantle.Nature Communications, Vol. 12, 1, doi:10.1038/s41467-021-26115-zMantlegeophysics - seismics

Abstract: The two most abundant minerals in the Earth’s lower mantle are bridgmanite and ferropericlase. The bulk modulus of ferropericlase (Fp) softens as iron d-electrons transition from a high-spin to low-spin state, affecting the seismic compressional velocity but not the shear velocity. Here, we identify a seismological expression of the iron spin crossover in fast regions associated with cold Fp-rich subducted oceanic lithosphere: the relative abundance of fast velocities in P- and S-wave tomography models diverges in the?~1,400-2,000 km depth range. This is consistent with a reduced temperature sensitivity of P-waves throughout the iron spin crossover. A similar signal is also found in seismically slow regions below?~1,800 km, consistent with broadening and deepening of the crossover at higher temperatures. The corresponding inflection in P-wave velocity is not yet observed in 1-D seismic profiles, suggesting that the lower mantle is composed of non-uniformly distributed thermochemical heterogeneities which dampen the global signature of the Fp spin crossover.
DS202202-0216
2021
Hernlund, J.W.Shephard, G.E., Houser, C., Hernlund, J.W., Valencia-Cardona, J.J., Tronnes, R.G., Wentzcovitch, R.M.Seismological expression of the iron spin crossover in ferropericlase in the Earth's lower mantle.Nature Communications, Vol. 12 5905 10.1038/s41467-021-26115-zMantletomography

Abstract: The two most abundant minerals in the Earth’s lower mantle are bridgmanite and ferropericlase. The bulk modulus of ferropericlase (Fp) softens as iron d-electrons transition from a high-spin to low-spin state, affecting the seismic compressional velocity but not the shear velocity. Here, we identify a seismological expression of the iron spin crossover in fast regions associated with cold Fp-rich subducted oceanic lithosphere: the relative abundance of fast velocities in P- and S-wave tomography models diverges in the?~1,400-2,000 km depth range. This is consistent with a reduced temperature sensitivity of P-waves throughout the iron spin crossover. A similar signal is also found in seismically slow regions below?~1,800 km, consistent with broadening and deepening of the crossover at higher temperatures. The corresponding inflection in P-wave velocity is not yet observed in 1-D seismic profiles, suggesting that the lower mantle is composed of non-uniformly distributed thermochemical heterogeneities which dampen the global signature of the Fp spin crossover.
DS201701-0014
2016
Heron, P.J.Heron, P.J., Pysklywec, R.N., Stephenson, R.Identifying mantle lithosphere inheritance in controlling intraplate orogenesis.Journal of Geophysical Research, Vol. 121, 9, pp. 6966-6987.MantleGeodynamics

Abstract: Crustal inheritance is often considered important in the tectonic evolution of the Wilson Cycle. However, the role of the mantle lithosphere is usually overlooked due to its difficulty to image and uncertainty in rheological makeup. Recently, increased resolution in lithosphere imaging has shown potential scarring in continental mantle lithosphere to be ubiquitous. In our study, we analyze intraplate deformation driven by mantle lithosphere heterogeneities from ancient Wilson Cycle processes and compare this to crustal inheritance deformation. We present 2-D numerical experiments of continental convergence to generate intraplate deformation, exploring the limits of continental rheology to understand the dominant lithosphere layer across a broad range of geological settings. By implementing a "jelly sandwich" rheology, common in stable continental lithosphere, we find that during compression the strength of the mantle lithosphere is integral in generating deformation from a structural anomaly. We posit that if the continental mantle is the strongest layer within the lithosphere, then such inheritance may have important implications for the Wilson Cycle. Furthermore, our models show that deformation driven by mantle lithosphere scarring can produce tectonic patterns related to intraplate orogenesis originating from crustal sources, highlighting the need for a more formal discussion of the role of the mantle lithosphere in plate tectonics.
DS201805-0950
2018
Heron, P.J.Heron, P.J., Pysklywec, R.N., Stephenson, R.Exploring the theory of plate tectonics: the role of mantle lithosphere structure.Geological Society of London, Special Publication, Vol. 470, doi:10.1144 /SP470.7Mantletectonics

Abstract: This review of the role of the mantle lithosphere in plate tectonic processes collates a wide range of recent studies from seismology and numerical modelling. A continually growing catalogue of deep geophysical imaging has illuminated the mantle lithosphere and generated new interpretations of how the lithosphere evolves. We review current ideas about the role of continental mantle lithosphere in plate tectonic processes. Evidence seems to be growing that scarring in the continental mantle lithosphere is ubiquitous, which implies a reassessment of the widely held view that it is the inheritance of crustal structure only (rather than the lithosphere as a whole) that is most important in the conventional theory of plate tectonics (e.g. the Wilson cycle). Recent studies have interpreted mantle lithosphere heterogeneities to be pre-existing structures and, as such, linked to the Wilson cycle and inheritance. We consider the current fundamental questions in the role of the mantle lithosphere in causing tectonic deformation, reviewing recent results and highlighting the potential of the deep lithosphere in infiltrating every aspect of plate tectonics processes.
DS201812-2817
2018
Heron, P.J.Heron, P.J., Pysklywec, R.N., Stephenson, R.Exploring the theory of plate tectonics: the role of mantle lithosphere structure.http://sp.lyellcollection.org, doi.org/10.1144/ SP470.7Mantleplate tectonics

Abstract: This review of the role of the mantle lithosphere in plate tectonic processes collates a wide range of recent studies from seismology and numerical modelling. A continually growing catalogue of deep geophysical imaging has illuminated the mantle lithosphere and generated new interpretations of how the lithosphere evolves. We review current ideas about the role of continental mantle lithosphere in plate tectonic processes. Evidence seems to be growing that scarring in the continental mantle lithosphere is ubiquitous, which implies a reassessment of the widely held view that it is the inheritance of crustal structure only (rather than the lithosphere as a whole) that is most important in the conventional theory of plate tectonics (e.g. the Wilson cycle). Recent studies have interpreted mantle lithosphere heterogeneities to be pre-existing structures and, as such, linked to the Wilson cycle and inheritance. We consider the current fundamental questions in the role of the mantle lithosphere in causing tectonic deformation, reviewing recent results and highlighting the potential of the deep lithosphere in infiltrating every aspect of plate tectonics processes.
DS201911-2532
2019
Heron, P.J.Heron, P.J.Mantle plumes and mantle dynamics in the Wilson Cycle.IN: Cycle Concepts in Plate Tectonics, editors Wilson and Houseman , Geological Society of London special publication 470, pp. 87-103.Mantleplate tectonics

Abstract: This review discusses the thermal evolution of the mantle following large-scale tectonic activities such as continental collision and continental rifting. About 300 myr ago, continental material amalgamated through the large-scale subduction of oceanic seafloor, marking the termination of one or more oceanic basins (e.g. Wilson cycles) and the formation of the supercontinent Pangaea. The present day location of the continents is due to the rifting apart of Pangaea, with the dispersal of the supercontinent being characterized by increased volcanic activity linked to the generation of deep mantle plumes. The discussion presented here investigates theories regarding the thermal evolution of the mantle (e.g. mantle temperatures and sub-continental plumes) following the formation of a supercontinent. Rifting, orogenesis and mass eruptions from large igneous provinces change the landscape of the lithosphere, whereas processes related to the initiation and termination of oceanic subduction have a profound impact on deep mantle reservoirs and thermal upwelling through the modification of mantle flow. Upwelling and downwelling in mantle convection are dynamically linked and can influence processes from the crust to the core, placing the Wilson cycle and the evolution of oceans at the forefront of our dynamic Earth.
DS201911-2533
2019
Heron, P.J.Heron, P.J., Pysklywec, R.N., Stephenson, R.Exploring the theory of plate tectonics: the role of mantle lithosphere.N: Cycle Concepts in Plate Tectonics, editors Wilson and Houseman , Geological Society of London special publication 470, pp. 137-155.Mantleplate tectonics

Abstract: This review of the role of the mantle lithosphere in plate tectonic processes collates a wide range of recent studies from seismology and numerical modelling. A continually growing catalogue of deep geophysical imaging has illuminated the mantle lithosphere and generated new interpretations of how the lithosphere evolves. We review current ideas about the role of continental mantle lithosphere in plate tectonic processes. Evidence seems to be growing that scarring in the continental mantle lithosphere is ubiquitous, which implies a reassessment of the widely held view that it is the inheritance of crustal structure only (rather than the lithosphere as a whole) that is most important in the conventional theory of plate tectonics (e.g. the Wilson cycle). Recent studies have interpreted mantle lithosphere heterogeneities to be pre-existing structures and, as such, linked to the Wilson cycle and inheritance. We consider the current fundamental questions in the role of the mantle lithosphere in causing tectonic deformation, reviewing recent results and highlighting the potential of the deep lithosphere in infiltrating every aspect of plate tectonics processes.
DS2002-0712
2002
Herppert, H.E.Herppert, H.E., Woods, A.W.The role of volatiles in magma chamber dynamicsNature, No. 6915, Dec. 5, pp. 493-5.MantleGeochemistry - not specific to diamonds
DS201510-1811
2015
Herrell, M.Vandenberg, J.A., Herrell, M., Faithful, J.W., Snow, A.M., Lacrampe, J., Bieber, C., Dayyani, S., Chisholm, V.Multiple modeling approach for the aquatic effects assessment of a proposed northern diamond mine development. Gahcho KueMine Water and the Environment, in press available, 19p.Canada, Northwest TerritoriesDeposit - Gahcho Kue

Abstract: Eight water models were used to assess potential aquatic environmental effects of the proposed Gahcho Kué diamond mine on groundwater and surface water flow and quality in the Northwest Territories, Canada. This sequence of models was required to cover different spatial and temporal domains, as well as specific physico-chemical processes that could not be simulated by a single model. Where their domains overlapped, the models were interlinked. Feedback mechanisms amongst models were addressed through iterative simulations of linked models. The models were used to test and refine mitigation plans, and in the development of aquatic component monitoring programs. Key findings generated by each model are presented here as testable hypotheses that can be evaluated after the mine is operational. This paper therefore offers a record of assumptions and predictions that can be used as a basis for post-validation.
DS201609-1754
2016
Herrell, M.Vandenberg, J.A., Herrell, M., Faithful, J.W., Snow, A.M., Lacrampe, J., Bieber, C., Dayyani, S., Chisholm, V.Multiple modeling approach for the aquatic effects assessment of a proposed northern diamond mine development.Mine Water and the Environment, Vol. 35, pp. 350-368.Canada, Northwest TerritoriesDeposit - Gahcho Kue

Abstract: Eight water models were used to assess potential aquatic environmental effects of the proposed Gahcho Kué diamond mine on groundwater and surface water flow and quality in the Northwest Territories, Canada. This sequence of models was required to cover different spatial and temporal domains, as well as specific physico-chemical processes that could not be simulated by a single model. Where their domains overlapped, the models were interlinked. Feedback mechanisms amongst models were addressed through iterative simulations of linked models. The models were used to test and refine mitigation plans, and in the development of aquatic component monitoring programs. Key findings generated by each model are presented here as testable hypotheses that can be evaluated after the mine is operational. This paper therefore offers a record of assumptions and predictions that can be used as a basis for post-validation.
DS201811-2596
2015
Herreno Daza, M.J.Ochoa, C.J.C., Herreno Daza, M.J., Fortaleche, D., Jimenez, J.F.Progress on the study of parameters related to the origin of Colombian diamonds.InColor, December pp. 88-97.South America, Colombiaemeralds
DS1930-0027
1930
Herrero, J.F.Herrero, J.F.Las Piedras Preciosas En la Joyeria Y En la IndustrieBarcelona: Agencia International De Liberia., 181P.GlobalProduction, Cutting, Diamonds, Compendium, Kimberley
DS1991-0948
1991
Herrero Bervera, E.Laj, C., Mazaud, A., Weeks, R., Fuller, M., Herrero Bervera, E.Geomagnetic reversal pathsNature, Vol. 351, June 6, p. 447GlobalGeophysics, Geomagnetics, Paleomagnetics
DS200412-0453
2004
Herres, N.Diehl, R., Herres, N.X ray fingerprinting routine for cut diamonds.Gems & Gemology, Vol. 40, 1, Spring, pp. 40-57.TechnologyDiamond, x-ray topography
DS201810-2334
2018
Herreweghe, A.Juncker, C., Herreweghe, A., DeLaunay, A.Les diamants de Golconde.Revue de Gemmologie A.F.G. IN: French, No. 202, pp. 22-26Indiahistory
DS1992-0705
1992
Herring, J.R.Herring, J.R.TIGRIS: a dat a model for an object-oriented geographic information SOURCE[ Computers and GeosciencesComputers and Geosciences, Vol. 18, No. 4, pp. 443-452GlobalComputer, Programs -Geographic information systems -TIGRIS
DS1996-0625
1996
Herring, T.A.Herring, T.A.The global positioning systemScientific American, February pp. 44-50GlobalGPS, Overview
DS200712-0116
2006
Herrington, R.Brown, D., Spadea, P., Puchkov, V., Alvarez-Marron, J., Herrington, R., Willner, A.P., Hetzel, R., Gorozhanina, Y., Juhlin, C.Arc continent collision in the southern Urals.Earth Science Reviews, in press availableRussia, UralsBaltica tectonics, UHP, geochemistry
DS201312-0382
2013
Herrington, R.Herrington, R.Road map to mineral supply. Not specific to diamondsNature Geoscience, 3p. On line Oct 13GlobalEconomics
DS200612-0574
2005
Herrington, R.J.Herrington, R.J., Puchkov, V.N., Yakubchuk, A.S.A reassessment of the tectonic zonation of the Uralides: implications for metallogeny.Geological Society of London Special Paper, No. 248, pp. 153-166.RussiaTectonics
DS200512-0425
2004
Herrmann, F.J.Herrmann, F.J., Bernabe, Y.Seismic singularities at upper mantle phase transitions: a site percolation model.Geophysical Journal International, Vol. 159, 3, pp. 949-960.MantleGeophysics - seismics
DS201807-1507
2018
Herrmann, R.B.Levandowski, W., Herrmann, R.B., Briggs, R., Boyd, O., Gold, R.An updated stress map of the continental United States reveals heterogeneous intraplate stress. TectonicsNature Geoscience, Vol. 11, 6, pp. 433-437.United Statesgeodynamics

Abstract: Knowledge of the state of stress in Earth’s crust is key to understanding the forces and processes responsible for earthquakes. Historically, low rates of natural seismicity in the central and eastern United States have complicated efforts to understand intraplate stress, but recent improvements in seismic networks and the spread of human-induced seismicity have greatly improved data coverage. Here, we compile a nationwide stress map based on formal inversions of focal mechanisms that challenges the idea that deformation in continental interiors is driven primarily by broad, uniform stress fields derived from distant plate boundaries. Despite plate-boundary compression, extension dominates roughly half of the continent, and second-order forces related to lithospheric structure appear to control extension directions. We also show that the states of stress in several active eastern United States seismic zones differ significantly from those of surrounding areas and that these anomalies cannot be explained by transient processes, suggesting that earthquakes are focused by persistent, locally derived sources of stress. Such spatially variable intraplate stress appears to justify the current, spatially variable estimates of seismic hazard. Future work to quantify sources of stress, stressing-rate magnitudes and their relationship with strain and earthquake rates could allow prospective mapping of intraplate hazard.
DS1900-0024
1900
Herron, F.M.Herron, F.M.Diamond in Indiana. #2Letter To G.f. Kunz, 1p.United States, Indiana, Great LakesDiamond Occurrence
DS201712-2679
2018
Hersh, G.Chen, C., Hersh, G., Fischer, K.M., Andronicos, C.L., Pavlis, G.L., Hamburger, M.W., Marshak, S., Larson, T., Yang, X.Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting.Earth and Planetary Science Letters, Vol. 481, pp. 223-235.United States, Illinois, Indiana, Kentuckygeophysics - seismics Reelfoot Rift

Abstract: Seismic discontinuities between the Moho and the inferred lithosphere-asthenosphere boundary (LAB) are known as mid-lithospheric discontinuities (MLDs) and have been ascribed to a variety of phenomena that are critical to understanding lithospheric growth and evolution. In this study, we used S-to-P converted waves recorded by the USArray Transportable Array and the OIINK (Ozarks-Illinois-Indiana-Kentucky) Flexible Array to investigate lithospheric structure beneath the central U.S. This region, a portion of North America's cratonic platform, provides an opportunity to explore how terrane accretion, cratonization, and subsequent rifting may have influenced lithospheric structure. The 3D common conversion point (CCP) volume produced by stacking back-projected Sp receiver functions reveals a general absence of negative converted phases at the depths of the LAB across much of the central U.S. This observation suggests a gradual velocity decrease between the lithosphere and asthenosphere. Within the lithosphere, the CCP stacks display negative arrivals at depths between 65 km and 125 km. We interpret these as MLDs resulting from the top of a layer of crystallized melts (sill-like igneous intrusions) or otherwise chemically modified lithosphere that is enriched in water and/or hydrous minerals. Chemical modification in this manner would cause a weak layer in the lithosphere that marks the MLDs. The depth and amplitude of negative MLD phases vary significantly both within and between the physiographic provinces of the midcontinent. Double, or overlapping, MLDs can be seen along Precambrian terrane boundaries and appear to result from stacked or imbricated lithospheric blocks. A prominent negative Sp phase can be clearly identified at 80 km depth within the Reelfoot Rift. This arrival aligns with the top of a zone of low shear-wave velocities, which suggests that it marks an unusually shallow seismic LAB for the midcontinent. This boundary would correspond to the top of a region of mechanically and chemically rejuvenated mantle that was likely emplaced during late Precambrian/early Cambrian rifting. These observations suggest that the lithospheric structure beneath the Reelfoot Rift may be an example of a global phenomenon in which MLDs act as weak zones that facilitate the removal of cratonic lithosphere that lies beneath.
DS1960-0813
1967
Hershey, G.Coons, R.L., Woolard, G.P., Hershey, G.Structural Significance and Analysis of Mid-continent Gravity HighAmerican Association of Petroleum Geologists Bulletin., Vol. 81, No. 12, PP. 2381-2399.GlobalGeophsyics, Mid-continent
DS1940-0008
1940
Hershey, J.W.Hershey, J.W.The Book of Diamonds, Their Curious Lore, Properties, Test sand Synthetic Manufacture.New York: Hearthside Press, 142P.GlobalKimberlite
DS200712-0432
2007
Hersum, T.G.Hersum, T.G., Marsh, B.D.Igneous textures: on the kinetics behind the words.Elements, Vol. 3, 4, August pp. 247-252.TechnologyClassification
DS1995-0412
1995
HertogenDemaiffe, D., Kampata, M., Weis, D., Moreau, J., HertogenThe Kundelungu kimberlites (Shaba, Zaire) petrology and geochemistry (trace elements and radiogenic isotopes).Proceedings of the Sixth International Kimberlite Conference Extended Abstracts, p. 129-31.Democratic Republic of CongoPetrology, geochemistry, review, Deposit -Kundelungu
DS1982-0206
1982
Hertogen, J.Fieremans, M., Hertogen, J., Demaiffe, D.Petrography, Geochemistry and Strontium Isotopic Composition of The Mbuji-mayi and Kundulungu Kimberlites (zaire).Proceedings of Third International Kimberlite Conference, TERRA, Vol. 2, No. 3, P. 213, (abstract.).Democratic Republic of Congo, Central AfricaKimberlite, Mineralogy, Petrography
DS1984-0277
1984
Hertogen, J.Fieremans, M., Hertogen, J., Demaiffe, D.Petrography, Geochemistry and Strontium Isotopic Composition of the Mbjui-mayi and Kundelungu Kimberlites (zaire).Proceedings of Third International Kimberlite Conference, Vol. 1, PP. 107-120.Democratic Republic of Congo, Central AfricaNodules, Mineral Chemistry, Geochronology, Isotope, History
DS1985-0279
1985
Hertogen, J.Hertogen, J., Lopez-Ruiz, J., et al.A Mantle Sediment Mixing Model for the Petrogenesis of A ultrapotassic lamproite from Southeast SpainEos, Vol. 66, No. 46, p. 1114 Abstract onlyGlobalLamproite
DS1985-0280
1985
Hertogen, J.Hertogen, J., Lopez-Ruiz, J., Rodriguez-Badiola, E., Demaiffe.A Mantle Sediment Mixing Model for the Petrogenesis of a Ultrapotassic Lamproite from Southeast Spain.Eos, Vol. 66, No. 46, NOVEMBER 12, P. 1114, (abstract.).GlobalPetrology
DS1985-0281
1985
Hertogen, J.Hertogen, J., Lopez-Ruiz, J., Rodriquez badiola, E., Demaiffe.Petrogenesis of Ultrapotassic Volcanic Rocks from Southeastern Spain: Trace Elements and Strontium-lead Isotopes.Geological Association of Canada (GAC)., Vol. 10, P. A26. (abstract.).SpainShoshonite, Lamproite
DS1985-0282
1985
Hertogen, J.Hertogen, J., Vanlerberghe, L., Namegabe, M.R.Geochemical Evolution of the Nyiragongo VolcanoBulletin. Geological Society Finland, Vol. 57, pt. 1-2 pp. 21-35Democratic Republic of CongoMeliltite, Leucitite, Rift, Tectonics
DS1986-0179
1986
Hertogen, J.Demulder, M., Hertogen, J., Deutsch, S., Andre, L.The role of crustal contamination in the potassic suite of theKarisimbi volcano (Virunga) African rift valleyChemical Geology, Vol. 57, No. 1-2, Dec. 15, pp. 117-136AfricaTectonics, Mantle genesis
DS1998-0873
1998
Hertogen, J.Liegeois, J.P., Navez, J., Hertogen, J., Black, R.Contrasting origin of post collisional high Potassium calc-alkaline and shoshonitic versus alkaline granitesLithos, Vol. 45, pp. 1-28.GlobalGeochemistry - sliding normalization, Shoshonites
DS200512-0381
2004
Hertogen, J.Guo, Z., Hertogen, J., Liu, J., Pasteels, P., Vocen, A.Potassic magmatism in western Sichuan and Yunnan Provinces, SE Tibet, China: petrological and geochemical constraints on petrogenesis.Journal of Petrology, Vol. 46, 1-2, pp. 33-78.China, TibetMagmatism
DS200512-1258
2005
Hertogen, J.Zheng Fu, G., Hertogen, J., Liu, J., Pasteels, A., Boven, L., Punzalan, H., Xiangiun, L., Zhang, W.Potassic magmatism in western Sichuan and Yunnan Provinces, SE Tibet, China: petrological and geochemical constraints on petrogenesis.Journal of Petrology, Vol. 46, 1, pp. 33-78.China, TibetMagmatism
DS200512-0426
2005
Hertweck, B.Hertweck, B., Ingrin, J.Hydrogen in corporation in a ring woodite analogue: Mg2 GeO4 spinel.Mineralogical Magazine, Vol. 69, 3, June, pp. 337-344.TechnologyRingwoodite
DS1859-0064
1839
Hertz, B.Hertz, B.A Catalogue of the Collection of Pearls and Precious Stones formed by Henry Phillip Hope.London: W. Clowes And Sons, 112P.Global Diamonds Notable
DS200912-0751
2009
Herv, R.L.Tenner, T.J., Hirschmann, M.M., Withers, A.C., Herv, R.L.Hydrogen partitioning between nominally anhydrous upper mantle minerals and melt between 3 and 5 GPa and applications to hydrous peridotite partial melting.Chemical Geology, Vol. 262, 1-2, May 15, pp. 42-56.MantleMelting
DS1997-0062
1997
Herve, F.Bahlburg, H., Herve, F.Geodynamic evolution and tectonostratigraphic terranes of northwesternArgentin a and northern ChileGeological Society of America (GSA) Bulletin, Vol. 109, No. 7, pp. 869-884Argentina, ChileTectonics, Gondwana, Paleozoic
DS2000-0914
2000
Herve, M.Sollner, F., Miller, H., Herve, M.An early Cambrian granodiorite age from Pre-Andean basement of Tierra del Fuego: the missing link...Journal of South American Earth Sciences, Vol. 13, No. 3, July pp. 163-77.South America, AntarcticaTectonics, Gondwanaland
DS1975-0493
1977
Hervig, R.L.Dawson, J.B., Smith, J.V., Hervig, R.L.Late Stage Diopside in Kimberlite MatrixNeues Jahrbuch f?r Mineralogie, PP. 529-543.South AfricaPetrography
DS1975-0760
1978
Hervig, R.L.Hervig, R.L., Smith, J.V., Steele, I.M.Mineral Chemistry of Fertile and Barren Harzburgites from The Upper Mantle Below South Africa.Geological Society of America (GSA), Vol. 10, No. 7, P. 420. (abstract.).South AfricaGeochemistry
DS1975-1226
1979
Hervig, R.L.Smith, J.V., Hervig, R.L., Ackermand, D., Dawson, J.B.Potassium, Rubidium, and Barium in Micas from Kimberlite and Peridotitic xenoliths and Implications for Origin of Basaltic Rocks.International Kimberlite Conference SECOND., Vol. 1, PP. 241-251.South Africa, Canada, Ontario, QuebecBasaltic Rocks, Kiberlites, Mica
DS1975-1227
1979
Hervig, R.L.Smith, J.V., Hervig, R.L., Ackermans, D., Dawson, J.B.Potassium, Rubidium and Barium in Micas from Kimberlites and Peridotitic xenoliths and Implications for Origin of Basaltic Rocks.Proceedings of Second International Kimberlite Conference, Proceedings Vol. 1, PP. 241-251.South AfricaMineralogy
DS1980-0171
1980
Hervig, R.L.Hervig, R.L., Smith, J.V., Steele, I.M., Dawson, J.B.Fertile and Barren Aluminum- Chromium Spinel Harzburgites from the UpperEarth and Planetary Science Letters, Vol. 50, PP. 41-58.South AfricaPetrology, Probe, Mineral Chemistry
DS1980-0172
1980
Hervig, R.L.Hervig, R.L., Smith, J.V., Steele, I.M., Gurney, J.J., Meyer, H.Diamonds: Minor Elements in Silicate Inclusions: Pressure Temperature Implications.Journal of Geophysical Research, Vol. 85, No. B 12, DECEMBER 10TH. PP. 6919=6929.GlobalMineralogy
DS1981-0131
1981
Hervig, R.L.Dawson, F.B., Hervig, R.L., Smith, J.V.Fertile Iron Rich Dunite Xenoliths from the Bultfontein Kimberlite, South Africa; Relationship to Other Mantle Peridotite Xenoliths.Fortschritte Der Mineralogie., Vol. 59, No. 2, PP. 303-324.South AfricaPetrography
DS1981-0215
1981
Hervig, R.L.Hervig, R.L., Smith, J.V.Dolomite-apatite Inclusion in Chromium Diopside Crystal, Bellsbank Kimberlite.American MINERALOGIST., Vol. 66, No. 3-4, PP. 346-349.South AfricaPetrography
DS1982-0200
1982
Hervig, R.L.Exley, R.A., Smith, J.V., Hervig, R.L.Cr- Rich Spinel and Garnet in Two Peridotite Xenoliths From the Frank Smith Mine South Africa: Significance of Al and Chromium Distribution between Spinel and Garnet.Mineralogical Magazine., Vol. 45, PP. 129-134.South AfricaCrystallography, Mineralogy, Nodules
DS1982-0271
1982
Hervig, R.L.Hervig, R.L., Smith, J.V.Temperature-dependent Distribution of Chromium between Olivine And Pyroxenes in Lherzolite Xenoliths.Contributions to Mineralogy and Petrology, Vol. 81, No. 3, PP. 184-189.GlobalBlank
DS1982-0272
1982
Hervig, R.L.Hervig, R.L., Smith, J.V.Temperature Dependent Distribution of Chromium between Olivine And Pyroxenes in Lherzolite Xenoliths.Contributions to Mineralogy and Petrology, Vol. 81, No. 3, PP. 184-189.South Africa, Solomon IslandsAlnoite, Kimberlite, Garnet, Lherzolite, Analyses, Petrography
DS1983-0194
1983
Hervig, R.L.Dawson, J.B., Hervig, R.L., Smith, J.V.Fertile iron rich dunite xenoliths from the Bultfontein kimberlite SouthAfrica.. addenduM.Fortschritte der Mineralogie, Vol.61, No. 1, p. 193South AfricaPetrology
DS1986-0010
1986
Hervig, R.L.Alexander, R.W.S., Dawson, J.B., Patterson, E.M., Hervig, R.L.The megacryst and inclusion assemblage from the Black Rock vent, AyrshireScottish Journal of Geology, Vol. 22, No. P2, pp. 203-212ScotlandPetrology, Inclusions
DS1989-0627
1989
Hervig, R.L.Hervig, R.L.Comment and reply on 'Metasomatic origin for iron-Ti rich multiphase inclusions in olivine from kimberlitexenolithsGeology, Vol. 17, No. 7, July pp. 675-677GlobalGenesis, Xenoliths
DS1996-0719
1996
Hervig, R.L.Kawamoto, T., Hervig, R.L., Holloway, J.R.Experimental evidence for a hydrous transition zone in the earth's mantleEarth and Planetary Science Letters, Vol. 142, No. 3/4, Aug. 1, pp. 587-592.MantlePetrology -experimental, Hydrous transition zone
DS1999-0537
1999
Hervig, R.L.Peacock, S.M., Hervig, R.L.Boron isotopic composition of subduction zone rocksChemical Geology, Vol. 160, No. 4, Sept. 2, pp. 281-90.MantleGeochronology, Subduction
DS2000-0501
2000
Hervig, R.L.King, P.L., Hervig, R.L., Dyar, M.D.Partitioning of Fe3 iron total between amphibole and basanitic melt as a function of oxygen fugacity.Earth and Planetary Science Letters, Vol. 178, No. 1-2, May 15, pp. 97-112.GlobalBasanite
DS200612-1161
2006
Hervig, R.L.Righter, K., Leeman, W.P., Hervig, R.L.Partitioning of Ni, Co and V between spinel structured oxides and silicate melts: importance of spinel composition.Chemical Geology, in pressTechnologyMantle melting
DS200912-0045
2009
Hervig, R.L.Bell, D.R., Hervig, R.L., Buseck, P.R., Aulbach, S.Lithium isotope analysis of olivine by SIMS: calibration of a matrix effect and application to magmatic phenocrysts.Chemical geology, Vol. 258, 1-2, Jan. pp. 5-16.Africa, South Africa, Tanzania, United StatesPhenocrysts
DS201312-0200
2013
Hervig, R.L.De Moor, M., Fischer, T.P., King, P.L., Botcharnikov, R.E., Hervig, R.L., Hilton, D.R., Barry, P.H., Mangasini, F., Ramirez, C.Volatile rich silicate melts from Oldoinyo Lengai volcano (Tanzania): implications for carbonatite genesis and eruptive behavior.Earth and Planetary Science Letters, Vol. 361, pp. 379-390.Africa, TanzaniaDeposit - Oldoinyo Lengai
DS201112-0439
2011
Herwartz, D.Hoffmann, J.E., Munker, C., Naeraa, T., Rosing, M.T., Herwartz, D., Garbe-Schonberg, Svahnberg, H.Mechanisms of Archean crust formation inferred from high precision HFSE systematics in TTGs.Geochimica et Cosmochimica Acta, Vol. 75, 15, pp. 4157-4178.Europe, GreenlandMantle melting
DS201112-0625
2011
Herwartz, D.Luget, A., Behrens, M., Herwartz, D., Pearson, D.G.Re-Os and Lu-Hf dating in Letlhakane peridotite xenoliths ( Botswana).Goldschmidt Conference 2011, abstract p.1365.Africa, BotswanaGeochronology, Magondi Belt
DS201508-0367
2015
Herwartz, D.Luguet, A., Behrens, M., Pearson, D.G., Konig, S., Herwartz, D.Significance of the whole rock Re-Os ages in cryptically and modally metasomatized cratonic peridotites: constraints from HSE-Se-Te systematics.Geochimica et Cosmochimica Acta, Vol. 164, pp. 441-463.Africa, BotswanaDeposit - Letlhakane
DS1999-0627
1999
HerweghSchaller, M., Steiner, O., Studer, I., Holzer, HerweghExhumation of Limpopo Central Zone granulites and dextral continent scale transcurrent movement...Precambrian Research, Vol. 96, No. 3-4. July, pp. 263-88.South AfricaPalala Shear Zone, Limpopo - tectonics
DS200812-0409
2008
Herweigh, M.Gies, J., Schreurs, G., Berger, A., Herweigh, M., Gnos, E.Indenter tectonics in central Madagascar.Geotectonic Research, Vol. 95, suppl. 1 pp. 51-53.Africa, MadagascarTectonics
DS200512-0427
2005
Herxberg, C.Herxberg, C.Mantle geochemistry: big lessons from little droplets.Nature, No. 7052, pp. 789-790.MantleGeochemistry
DS200612-1098
2006
Herxberg, C.Polat, A., Herxberg, C., Munker, C., Rodgers, R., Kusky, T., Li, J., Fryer, B.Geochemical and petrological evidence for a supra subduction zone origin of Neoarchean (ca 2.5 Ga) peridotites, central orogenic belt, North Chin a craton.Geological Society of America Bulletin, Vol. 118, 7, July pp. 771-784.ChinaPeridotite, picrites
DS1989-0110
1989
Herz, D.L.Berg, J.H., Moscati, R.J., Herz, D.L.A petrologic geotherm from a continental rift in AntarcticaEarth and Planetary Science Letters, Vol. 93, No. 1, May pp. 98-108AntarcticaGeothermometry
DS1989-0224
1989
Herz, N.Carr, D.D., Herz, N.Mineral resources.. concise encyclopediaMit Press, 449p. $ 145.00BookMineral resources, Encyclopedia
DS1988-0300
1988
Herzberg, C.Herzberg, C., Feigenson, M., kuba, C., Ohtani, E.Majorite fractionation recorded in the geochemistry of peridotites from South AfricaNature, Vol. 332, No. 6167, April 28, pp. 823-826South AfricaBlank
DS1990-0686
1990
Herzberg, C.Herzberg, C.Melting experiments in ultramafic systems to 165 kilobarsV.m. Goldschmidt Conference Held May 2-4, 1990, Program And Abstract, p. 53. Abstract onlyGlobalMantle peridotite, Experimental petrology
DS1991-0708
1991
Herzberg, C.Herzberg, C., Gasparik, T.Garnet and pyroxenes in the mantle: a test of the majorite fractionationhypothesisJournal of Geophysical Research, Vol. 94, No. B 10, Sept. 10, pp. 16, 263-16, 274GlobalMantle, Experimental petrology
DS1992-0706
1992
Herzberg, C.Herzberg, C.Depth and degree of melting of komatiitesJournal of Geophysical Research, Vol. 97, No. B4, April 10, pp. 4521-4540GlobalKomatiites, Genesis
DS1995-0790
1995
Herzberg, C.Herzberg, C.Generation of plume magmas through time: an experimental perspectiveChemical Geology, Vol. 126, No. 1, Nov. 20, pp. 1-16GlobalMagma genesis, Plumes
DS1996-0626
1996
Herzberg, C.Herzberg, C., Zhang, J.Melting experiments on anhydrous peridotite KLB-1: compositions of magmas in the upper mantle, transitionJournal of Geophysical Research, Vol. 101, No. B4, April 10, pp. 8271-95.MantlePeridotite, Melt
DS1997-0502
1997
Herzberg, C.Herzberg, C., Zhang, J.Melting experiments on komatiite analog compositions at 5 GPaAmerican Mineralogist, Vol. 82, pp; 354-67.GlobalPetrology - experimental, Garnets
DS1998-0616
1998
Herzberg, C.Herzberg, C., O'Hara, M.J.Phase equilibrium constraints on the origin of basalts, picrites andkomatiites.Earth Science Reviews, Vol. 44, No. 1-2, July pp. 39-79.South Africa, IcelandPeridotites, Craton, lithosphere, mantle plumes, Petrology, Picrites
DS2000-0001
2000
Herzberg, C.Abbott, D., Sparks, D., Herzberg, C., Mooney, W., et al.Quantifying Precambrian crustal extraction: the root is the answerTectonophysics, Vol. 322, No. 1-2, pp.163-90.MantleTectonics - root
DS2002-0713
2002
Herzberg, C.Herzberg, C., O'Hara, M.J.Plume associated ultramafic magmas of Phanerozoic ageJournal of Petrology, Vol. 43, No. 10, Oct.pp. 1857-1884.GlobalHot spots, Magmatism
DS200512-0028
2005
Herzberg, C.Arndt, N.T., Herzberg, C.The temperature of mantle plumes.Chapman Conference held in Scotland August 28-Sept. 1 2005, 1p. abstractUnited States, HawaiiMantle plume, geothermometry
DS200512-0428
2004
Herzberg, C.Herzberg, C.Geodynamic information in peridotite petrology.Journal of Petrology, Vol. 45, 12, Dec. pp. 2507-2530.MantleTectonics
DS200512-0785
2004
Herzberg, C.Niu, Y., Herzberg, C., Wilson, M.Magma generation and evolution in the Earth. Two page foreward to issue. Papers cited seperately.Journal of Petrology, Vol. 45, 12, Dec. pp. 2347-48.Magmatism
DS201012-0275
2010
Herzberg, C.Herzberg, C., Condie, K., Korenaga, J.Thermal history of the Earth and its petrological expression.Earth and Planetary Science Letters, Vol. 292, 1-2, pp. 79-88.MantleGeothermometry
DS201112-0432
2011
Herzberg, C.Herzberg, C.Basalts as temperature probe's of Earth's mantle.Geology, Vol. 39, 12, pp. 1179-1180.MantlePeridotite, melting
DS201212-0296
2012
Herzberg, C.Herzberg, C., Rudnick, R.Formation of cratonic lithosphere: an integrated thermal and petrological model.Lithos, Vol. 149, pp. 4-15.MantleMelting
DS201212-0297
2012
Herzberg, C.Herzberg, C., Rudnick, R.Formation of cratonic lithosphere: an integrated thermal and petrological model.Lithos, in press available, 41p.GlobalCraton
DS201212-0597
2012
Herzberg, C.Rooney, T.O., Herzberg, C., Bastow, I.D.Elevated mantle temperature beneath East Africa.Geology, Vol. 40, 1, pp. 27-30.Africa, Ethiopia, KenyaMagmatism
DS201212-0606
2012
Herzberg, C.Rudnick, R.L., Herzberg, C.Origin of Archean cratons by diapiric ascent of foundered shallow residues.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalCraton
DS201312-0383
2013
Herzberg, C.Herzberg, C.Petrological evidence for deep lower mantle melting.Goldschmidt 2013, AbstractCanada, Nunavut, Baffin Island, GreenlandPicrite
DS201610-1870
2016
Herzberg, C.Herzberg, C., Vidito, C., Starkey, N.A.Nickel cobalt contents of olivine record origins of mantle peridotite and related rocks.American Mineralogist, Vol. 101, pp. 1952-1966.MantlePeridotite

Abstract: Olivine is distinguished from all other minerals in providing a remarkable chemical narrative about magmatic processes that occurred in Earth’s crust, mantle, and core over the entire age of Earth history. Olivines in mantle peridotite have Ni contents and Mg numbers that were largely produced by equilibrium crystallization in an early turbulently convecting magma ocean; subsequent stages of partial melting operated to slightly elevate Ni and Mg number in residual olivines. Olivines from Archean komatiites from the Abitibi greenstone belt have Ni contents and Mg numbers that are consistent with an extensively melted peridotite source at great depths in the mantle. Olivines from basaltic oceanic crust, the Icelandic mantle plume and other Phanerozoic occurrences have compositions that record magma chamber crystallization, recharge, mixing, and partial melting. Olivines from the present-day Icelandic mantle plume have compositions that are consistent the melting of a peridotite source; unlike Hawaii, the melting of recycled crust as a distinct pyroxenite lithology is not evident in the olivine chemistry of Iceland. Paleocene picrites from Baffin Island and West Greenland from the ancient Icelandic plume have olivines with Ni contents that are consistent with either Ni-rich peridotite that formed by core-mantle interaction or by low-pressure crystallization of hot and deep magmas. In general, hot magma oceans, mantle plumes, and ambient mantle magmatism form in ways that are captured by the compositions of the olivine crystals that they contain.
DS201901-0041
2018
Herzberg, C.Herzberg, C.From hot oceanic ridges to cool cratons. Peridotite Geology, Vol. 4, 12, pp. 1079-1080.Mantlesubduction

Abstract: The fraction of radioactive heat production in Earth’s mantle to convective heat loss has decreased with the aging of Earth, as more of its nuclear fuel became spent and more of its heat was lost to space. Earth was therefore hotter in its past, but there is no consensus as to how much higher the mantle’s temperature was in early Earth compared to the present. This is an important problem to understand because it is expected to have imposed secular changes in the formation of oceanic lithosphere at ridges and its cycling at subduction zones (Herzberg and Rudnick, 2012; Foley, 2018). In a hotter early Earth, the ambient mantle melted more extensively, to make thicker basaltic oceanic crust and residual mantle peridotite, the latter of which was depleted in chemical elements that entered the magmas. Sometime later, the basaltic oceanic crust became hydrated by seawater, and it in turn melted to make silicic continental crust. As discussed in more detail below, this transformation led to the juxtaposition of continental crust on top of oceanic lithospheric mantle (Herzberg and Rudnick, 2012). The original “oceanic mantle lithosphere” is now called "continental mantle lithosphere" because it is located below continental crust in cratons. This hypothesis is explored by Servali and Korenaga (2018, p. 1047 in this issue of Geology), and is the reason why they entitle their paper an "oceanic origin of continental mantle lithosphere".
DS1986-0617
1986
Herzberg, C.I.Ohtani, B., Herzberg, C.I.Stability of lherzolite magmas at solidus temperatures and 20 GPAEos, Vol. 67, No. 16, April 22, p. 408. AbstractGlobalLherzolites
DS1985-0283
1985
Herzberg, C.T.Herzberg, C.T., O'hara, M.J.Origin of Mantle Peridotite and Komatiite by Partial MeltingGeophysical Research. LETTERS, Vol. 12, No. 9, SEPTEMBER PP. 541-544.GlobalPetrology
DS1993-0657
1993
Herzberg, C.T.Herzberg, C.T.Lithosphere peridotites of the Kaapvaal craton. #1Earth and Planetary Science Letters, Vol. 120, No. 1-2, November, pp. 13-30.South AfricaCraton, Peridotites
DS1993-0658
1993
Herzberg, C.T.Herzberg, C.T.Lithosphere peridotites of the Kaapvaal craton. #2Earth and Planetary Science Letters, Vol. 120, No. 3-4, December, pp. 13-30.South AfricaCraton, Peridotites
DS1993-0659
1993
Herzberg, C.T.Herzberg, C.T.Lithosphere peridotites of the Kaapvaal cratonEarth and Planetary Science Letters, Vol. 120, No. 3/4 December pp. 13-30South AfricaLithosphere, Craton -Kaapvaal
DS1982-0273
1982
Herzberg, W.Herzberg, W.The Mineral Deposits of South AfricaGluckauf., Vol. 118, No. 5, MARCH PP. 279-286.South AfricaDiamonds, Commodity Surveys
DS1988-0301
1988
Herzfeld, U.C.Herzfeld, U.C., Sondergard, M.A.MAPCOMP- a Fortran program for weighted Thematic Map comparisonComputers and Geosciences, Vol. 14, No. 5, pp. 699-714. Database # 17573GlobalComputer, Program- MAPCOMP
DS1994-0390
1994
Herzfeld, U.C.Davis, J.C., Herzfeld, U.C.Computers in geology - 25 years of progressOxford University Press, 320pGlobalComputer programs -applied, Book -ad
DS2001-0758
2001
HerzigMcInnes, B.I.A., Gregoire, Binss, Herzig, HanningtonHydrous metasomatism of oceanic sub arc mantle: petrology, geochemistry of fluid metasom. mantle wedgeEarth and Planetary Science Letters, Vol. 188, No. 1, May 30, pp.169-83.Papua New GuineaXenoliths, Metasomatism - not specific to diamonds
DS2002-1426
2002
Herzig, P.Schwarz-Schampera, U., Herzig, P.Indium - geology, mineralogy and economicsSpringer-ny.com/newspreviews, 257p. approx. $110.GlobalBook - ad, Indium - geology, petrology, stockwork tin
DS2002-0478
2002
Herzig, P.M.Franz, L., Becker, K.P., Kramer, W., Herzig, P.M.Metasomatic mantle xenoliths from the Bismarck microplate - thermal evolution, geochemistry...Journal of Petrology, Vol. 43, No. 2, pp. 315-44.Papua New GuineaSlab induced metasomatism - not specific to diamond, Xenoliths
DS2002-1106
2002
Herzig, P.M.Muller, D., Herzig, P.M., Scholten, J.C., Hunt, S.Ladolam gold deposit, Lihir Island, Papua New Guinea: gold mineralization hosted by alkaline rocks.Society of Economic Geologists Special Publication, No.9,pp.367-82.Papua New GuineaGold, metallogeny, Deposit - Ladolam
DS201506-0273
2015
Herzog, F.A.Herzog, F.A.The potential of a portable EDXRF spectrometer for gemmology. ( not specific to diamond)The Journal of Gemmology, Vol. 34, 5, pp. 404-418.TechnologySpectroscopy
DS1960-0942
1968
Herzog, L.F.Deines, P., Gold, D.P., Herzog, L.F.Variability of C 13 and O 18 in Carbonates from a Mica Peridotite Dike Near Dixonville.Geological Society of America (GSA) SPECIAL PAPER., No. 101, PP. 51-52.United States, Appalachia, PennsylvaniaGeochronology, Carbon
DS1996-0627
1996
Heslop, J.B.Heslop, J.B.Mantaining Canada's share of exploration dollars is keyProspectors and Developers Association of Canada (PDAC) in Brief, No. 9, May 1pCanadaExploration
DS1860-0991
1897
Heslop, W.J.Heslop, W.J.Later Volcanic Eruptions on the WitwatersrandGeological Society South Africa Transactions, Vol. 3, PP. 49-52.Africa, South AfricaGemology
DS1993-0660
1993
Hess, A.E.Hess, A.E.A wireline powered inflatable packer for borehole applicationsUnited States Geological Survey (USGS) Open File, No. 93-485, 19p. $ 3.50GlobalGeophysics -borehole
DS201605-0827
2016
Hess, K-U.Di Genova, D., Cimarelli, C., Hess, K-U., Dingwell, D.B.An advanced rotational rheometer system for extremely fluid liquids up to 1273 K and applications to alkali carbonate melts.American Mineralogist, Vol. 101, pp. 953-959.MantleCarbonatite

Abstract: A high-temperature rheometer equipped with a graphite furnace, characterized by an air-bearing-supported synchronous motor, has been enhanced by a custom-made Pt-Au concentric cylinder assembly. With this adaptation, viscosity measurements of highly fluid melts can be achieved at high temperatures, up to 1273 K. Due to the air-bearing-supported motor, this apparatus can perform measurements of extremely low torque ranging between 0.01 ?Nm and 230 mNm (resolution of 0.1 nNm), extending the typical range of viscosity measurements accessible in the present configuration to 10?3.5-103.5 Pa•s and shear rates up to 102 of s?1. We calibrated the system with distilled water, silicone oils, and the DGG-1 standard glass. We further present new data for the viscosity of Na2CO3, K2CO3, and Li2CO3 liquids. Finally, a comparison between our results and literature data is provided, to illustrate the effect of chemical composition and oxygen fugacity on the viscosity of alkali carbonate melts, which serve as analogs for both carbonatitic melts and molten carbonates of industrial relevance. This study substantially improves the database of alkali carbonate melts and dramatically increases the accuracy with respect to previous measurement attempts. The very low viscosity range data and their temperature dependence also helps to constrain very well the activation energy of these highly fluid systems and confirms the estimate of a universal pre-exponential factor for non-Arrhenian viscosity-temperature relationships.
DS1989-0628
1989
Hess, P.C.Hess, P.C.Origins of igneous rocks.Chapter 16, Kimberlites and Chapter 17Continental RiftsHarvard University of Press, Chapter 16, pp. 245-262, Chapter 17 pp. 263-275MidcontinentIgneous rocks, Kimberlites, lamproites
DS201706-1078
2017
Hess, T.L.Hess, T.L., Carter, M., Sundell, K.The search for diamonds in the Laramie Mountains of the Wyoming Archean province, USA.GSA Annual Meeting, 1p. AbstractUnited States, Wyoming, Colorado Plateaudeposit - Iron Mountain

Abstract: Casper College undergraduate students investigated the feasibility of finding hidden kimberlite pipes by means of geological mapping, geophysics, and stream sediment sampling. The Precambrian Laramie Mountains of southeastern Wyoming, locally known as the Iron Mountain Kimberlite district, was chosen based on previous work conducted by the Wyoming State Geological Survey (WSGS), geology of the region, and known kimberlite pipes. Data was collected using micro gravimeter - Scintrex CG-5, magnetometer - G-858 MagMapper, and electrical resistivity - SuperSting R8/IP/SP. Target one was chosen while pre-mapping the area and a topographic bowl like depression was identified. Micro gravimeter data was collected on a 56m transect at 8m intervals. Magnetometer data was collected in an area of 122m by 92m running in a 8m parallel array. Electrical resistivity was collected along a 56m transect at 8m intervals. Target two was chosen because the WSGS identified a regional magnetic anomaly and follow-up research was needed. Microgravimeter data was collected on a 56m transect at 8m intervals. Magnetometer data was collected from an area of 122m by 92m running in an 8m parallel array. Electrical resistivity was collected along a 56m transect at 8m intervals. Two drill site locations were selected based on the geophysical results to prove kimberlite is present at depth. Sediment samples were taken along Middle Sybille Creek and yielded a variety of pink to very deep red and purple colored garnets which have been sent in for EPMA (electron probe micro analyses) testing to determine the garnet-spinel compositions. Once complete the geochemical analyses will help determine if either target has a greater potential to be a diamondiferous kimberlite pipe.
DS2003-0507
2003
Hesse, M.Grove, T.L., Elkins-Tanton, L.T., Hesse, M.Melting processes in continental lithosphere: effects of mantle metasomatism on meltGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.395.California, MexicoMetasomatism - not specific to diamonds
DS2003-0579
2003
Hesse, M.Hesse, M., Grove, T.L.Absarokites from the western Mexican Volcanic Belt: constraints on mantle wedgeContributions to Mineralogy and Petrology, Vol. 146, 1, Oct. pp. 10-27.MexicoMantle wedge - Jalico Block, metasomatism - not specifi
DS200412-0730
2003
Hesse, M.Grove, T.L., Elkins-Tanton, L.T., Hesse, M.Melting processes in continental lithosphere: effects of mantle metasomatism on melt composition.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.395.United States, CaliforniaMetasomatism - not specific to diamonds
DS200412-0820
2003
Hesse, M.Hesse, M., Grove, T.L.Absarokites from the western Mexican Volcanic Belt: constraints on mantle wedge conditions.Contributions to Mineralogy and Petrology, Vol. 146, 1, Oct. pp. 10-27.MexicoMantle wedge - Jalico Block, metasomatism - not specifi
DS201706-1104
2017
Hesse, M.A.Smye, A.J., Jackson, C.R.M., Konrad-Schnolke, M., Hesse, M.A., Parman, S.W., Shuster, D.L., Ballentine, C.J.Noble gases recycled into the mantle through cold subduction zones.Earth and Planetary Science Letters, Vol. 471, pp. 65-73.Mantlegeochemistry, water cycle

Abstract: Subduction of hydrous and carbonated oceanic lithosphere replenishes the mantle volatile inventory. Substantial uncertainties exist on the magnitudes of the recycled volatile fluxes and it is unclear whether Earth surface reservoirs are undergoing net-loss or net-gain of H2O and CO2. Here, we use noble gases as tracers for deep volatile cycling. Specifically, we construct and apply a kinetic model to estimate the effect of subduction zone metamorphism on the elemental composition of noble gases in amphibole - a common constituent of altered oceanic crust. We show that progressive dehydration of the slab leads to the extraction of noble gases, linking noble gas recycling to H2O. Noble gases are strongly fractionated within hot subduction zones, whereas minimal fractionation occurs along colder subduction geotherms. In the context of our modelling, this implies that the mantle heavy noble gas inventory is dominated by the injection of noble gases through cold subduction zones. For cold subduction zones, we estimate a present-day bulk recycling efficiency, past the depth of amphibole breakdown, of 5-35% and 60-80% for 36Ar and H2O bound within oceanic crust, respectively. Given that hotter subduction dominates over geologic history, this result highlights the importance of cooler subduction zones in regassing the mantle and in affecting the modern volatile budget of Earth's interior.
DS1988-0302
1988
Hesse, R.Hesse, R.Diagenesis # 13Origin of chert: diagenesis of biogenicsiliceoussedimentsGeoscience Canada, Vol. 15, No. 3, pp. 171-192GlobalDiagenesis, Chert
DS1989-0629
1989
Hesse, R.Hesse, R.Silica diagenesis: origin of inorganic and replacement chertsEarth Science Reviews, Vol. 26, No. 4, August pp. 253-GlobalSilica, Review
DS1986-0361
1986
Hesselbo, S.P.Hesselbo, S.P.Pseudoleucite from the Gardar of South GreenlandBulletin. Geological Society Denmark, Vol. 35, pp. 11-17GreenlandC.K. Brooks, J. Gittins, Vol. 36, pp. 337-338, 1987, Gardar
DS2003-0610
2003
Hessler, E.Humphreys, E., Hessler, E., Ducker, K., Farmer, G.L., Erlsev, E., Atwater, T.How Laramide age hydration of North America lithosphere by the Farallon slabInternational Geology Review, Vol. 45, 7, July pp. 575-595.Colorado, WyomingTectonics
DS2003-0611
2003
Hessler, E.Humphreys, E., Hessler, E., Dueker, K., Farmer, G.L., Erslev, E., Atwater, T.How Laramide age hydration of North American lithosphere by the Farallon SlabInternational Geology Review, Vol. 45, 7, July pp. 575-95.Wyoming, ColoradoSubduction
DS200412-0858
2003
Hessler, E.Humphreys, E., Hessler, E., Dueker, K., Farmer, G.L., Erslev, E., Atwater, T.How Laramide age hydration of North American lithosphere by the Farallon Slab controlled subsequent activity in the Western UnitInternational Geology Review, Vol. 45, 7, July pp. 575-95.United States, WyomingSubduction
DS1992-1369
1992
Hesson, H.Jr.Sexton, J.L., Hesson, H.Jr.Seismic reflection and gravity profile models of dat a from Lake SuperiorEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 320OntarioMidcontinent Rift, Gravity
DS1993-0661
1993
Hester, B.Hester, B.Opportunities for mining investment in third world Africa- styles of project financing in a changing sceneSociety for Mining, Metallurgy and Exploration (SME) Meeting held February 15-18, 1993 in Reno, Nevada, Reprint No. 93-137, 3pGhana, Ethiopia, Guinea, Mali, Ivory CoastEconomics, Financing
DS1993-0662
1993
Hester, B.Hester, B.Opportunities for mining investment in third world AfricaMining Engineering, Vol. 45, No. 8, August pp. 1016-1021Ghana, Ethiopia, Ivory Coast, Guinea, MaliEconomics, Mining investment
DS1991-0709
1991
Hester, B.M. Inc.Hester, B.M. Inc.Opportunities for mineral resource development in Tanzania. Very brief pages of historical interest on William son and diamonds in TanzaniaUnited Nations Development Agency, pp. 78-85TanzaniaKimberlite, Carbonatite
DS1990-0687
1990
Hester, B.W.Hester, B.W., Buchan, K.L., Card, K.D., Chandler, F.W.Multiple ages of Nipissing diabase intrusion: paleo-magnetic evidence from the Englehart area, Ontario:discussionCanadian Journal of Earth Sciences, Vol. 7, No. 1, January pp. 159-161OntarioGeophysics -paleomagnetics, Diabase-Nipissing
DS1993-0663
1993
Hester, B.W.Hester, B.W.Tanzania awakens to its mineral opportunitiesEngineering and Mining Journal, Vol. 194, No. 6, September pp. 16e, f, h, j, l, m, nTanzaniaEconomics, Mining operations/exploration
DS1997-0503
1997
Hester, B.W.Hester, B.W.Tanzania: opportunities for mineral resource developmentAfrica Mineral Resource Specialists Inc, 108p. $ 50. United StatesTanzaniaBook - ad, Mineral resources
DS1990-0688
1990
Hester, M.G.Hester, M.G., Springett, M.W.Geostatistics and kriging: surviving in the real worldAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 90-92, 10pGlobalGeostatistics, Kriging
DS1995-0007
1995
Hester, M.G.Adisoma, G.S., Hester, M.G.Grade estimation and its precision in mineral resources: the jackknifeapproachAmerican Institute of Mining, Metallurgical, and Petroleum Engineers (AIME) Preprint, No. 95-59, 8pArizonaCopper, Geostatistics -jackknife
DS1996-0005
1996
Hester, M.G.Adisoma, G.S., Hester, M.G.Grade estimation and its precision in mineral resources: the jacknifeapproachMining Engineering, Vol. 48, No. 2, Feb. pp. 84-88United StatesOre reserves, geostatistics, Kriging, Jacknife approach
DS1860-0033
1867
Het VolksbadHet VolksbadEen Kaapsche DiamantHet Volksblad., APRIL 18TH.Africa, South AfricaHistory, Diamond
DS200712-0433
2006
Hetenyi, G.Hetenyi, G., Cattin, R., Vergne, J., Nabelek, J.L.The effective elastic thickness of the India Plate from receiver function imaging, gravity anomalies and thermomechanical modelling.Geophysical Journal International, Vol. 167, 3, Dec. 1, pp. 1106-1108.IndiaGeophysics - gravity
DS200712-0434
2007
Hetenyl, G.Hetenyl, G., Cattin, R., Brunet, F., Bollinger, L., Vergne, J., Nabalek, J.L., Diament, M.Density distribution of the India plate beneath the Tibetan plateau: geophysical and petrological constraints on kinetics of lower crustal eclogitizationEarth and Planetary Science Letters, Vol. 264, 1-2, pp. 226-244.Asia, IndiaEclogite
DS202004-0506
2020
Hetet, G.Delord, T., Huillery, P., Nicolas, L., Hetet, G.Spin-cooling of the motion of trapped diamond.Nature, March 23, in press available Globalnitrogen

Abstract: Observing and controlling macroscopic quantum systems has long been a driving force in quantum physics research. In particular, strong coupling between individual quantum systems and mechanical oscillators is being actively studied. Whereas both read-out of mechanical motion using coherent control of spin systems and single-spin read-out using pristine oscillators have been demonstrated, temperature control of the motion of a macroscopic object using long-lived electronic spins has not been reported. Here we observe a spin-dependent torque and spin-cooling of the motion of a trapped microdiamond. Using a combination of microwave and laser excitation enables the spins of nitrogen-vacancy centres to act on the diamond orientation and to cool the diamond libration via a dynamical back-action. Furthermore, by driving the system in the nonlinear regime, we demonstrate bistability and self-sustained coherent oscillations stimulated by spin-mechanical coupling, which offers the prospect of spin-driven generation of non-classical states of motion. Such a levitating diamond-held in position by electric field gradients under vacuum-can operate as a ‘compass’ with controlled dissipation and has potential use in high-precision torque sensing, emulation of the spin-boson problem15 and probing of quantum phase transitions. In the single-spin limit and using ultrapure nanoscale diamonds, it could allow quantum non-demolition read-out of the spin of nitrogen-vacancy centres at ambient conditions, deterministic entanglement between distant individual spins and matter-wave interferometry.
DS200812-0567
2008
Hetherington, C.J.Kietavainen, R., Woodard, J., Eklund, O., Hetherington, C.J., BoettcherApatite as a petrogenetic indicator for lamprophyres and carbonatites.Goldschmidt Conference 2008, Abstract p.A469.Europe, FennoscandiaChemistry - trace elements
DS200812-1263
2008
Hetherington, C.J.Woodard, J., Hetherington, C.J., Huhma, H.Sr Sm and Nd isotope geochemistry and U Th Pb geochronology of the Naantali carbonatite, SW Finland.Goldschmidt Conference 2008, Abstract p.A1033.Europe, FinlandCarbonatite
DS201412-0991
2014
Hetherington, C.J.Woodard, J., Hetherington, C.J.Carbonatite in a post collisional tectonic setting: geochronology and emplacement conditions at Naantali, SW Finland.Precambrian Research, Vol. 240, pp. 94-107.Europe, FinlandCarbonatite
DS200512-0429
2004
Hetland, E.A.Hetland, E.A., Hager, B.H.Relationship of geodetic velocities to velocities in the mantle.Geophysical Research Letters, Vol. 31, 17, Sept. 16, L17604.MantleGeophysics
DS2003-1458
2003
Hetman, C.Webb, K., Scott Smith, B., Paul, J., Hetman, C.Geology of the Victor kimberlite, Attawapiskat, northern Ontario, Canada: cross8th. International Kimberlite Conference Large Core Exhibit volume, 5p.Ontario, AttawapiskatGeology - overview, Deposit - Victor
DS200412-0821
2004
Hetman, C.Hetman, C.The Knife Lake kimberlite, Nunavut, Canada: exploration geology.PDAC 2004, 1p. abtract.Canada, NunavutDeposit - Knife Lake geology
DS200412-2091
2003
Hetman, C.Webb, K., Scott Smith, B., Paul, J., Hetman, C.Geology of the Victor kimberlite, Attawapiskat, northern Ontario, Canada: cross cutting and nested craters.8th. International Kimberlite Conference Large Core Exhibit volume, 5p.Canada, Ontario, Attawapiskat, James Bay LowlandsGeology - overview Deposit - Victor
DS200612-0529
2006
Hetman, C.Harder, M., Hetman, C., Scott Smith, B., Pell, J.Geology of the DO27 pipe: a pyroclastic kimberlite in the Lac de Gras Province, NWT, Canada.Emplacement Workshop held September, 5p. extended abstractCanada, Northwest TerritoriesDeposit - DO27, geology
DS200612-1514
2006
Hetman, C.Webb, K.J., Scott Smith, B., Paul, J., Hetman, C.Geology of the Victor kimberlite, Attawapiskat, northern Ontario, Canada: cross cutting and nested craters.Emplacement Workshop held September, 5p. abstractCanada, OntarioDeposit - Victor geology
DS200712-0412
2006
Hetman, C.Harder, M., Hetman, C., Scott Smith, B., Pell, J.Geology model of the DO27 pipe.34th Yellowknife Geoscience Forum, p. 82. abstractCanada, Northwest TerritoriesTli Kwi Cho complex
DS200912-0134
2009
Hetman, C.Crawford, B., Hetman, C., Nowicki, T., Baumgartner, M., Harrison, S.The geology and emplacement history of the Pigeon kimberlite, EKATI diamond mine, Northwest Territories, Canada.Lithos, In press - available 35p.Canada, Northwest TerritoriesDeposit - Pigeon
DS200912-0240
2009
Hetman, C.Galloway, M., Nowicki, T., Van Coller, B., Mukodzani, B., Siemens, K., Hetman, C., Webb, K., Gurney, J.Constraining kimberlite geology through integration of geophysical, geological and geochemical methods: a case study of the Mothae kimberlite, northern Lesotho.Lithos, In press - available 47p.Africa, LesothoDeposit - Mothae
DS201212-0493
2012
Hetman, C.Moss, S., Nowicki, T., Hetman, C., Freeman, L.,Abedu, B.Geology and evaluation of kimberlite dykes at Koidu, Sierra Leone.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, Sierra LeoneDeposit - Koidu
DS201212-0495
2012
Hetman, C.Moss, S., Webb, K., Hetman, C., Manyumbu, A., Muchechetere, C.Geology of the K1 and K2 kimberlite pipes at Murowa, Zimbabwe.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, ZimbabweDeposit - Murowa
DS201312-0614
2013
Hetman, C.Moss, S., Webb, K., Hetman, C.Geology of the K1 and K2 kimberlite pipes at Murowa, Zimbabwe.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 35-50.Africa, ZimbabweDeposit - Murowa
DS201412-0598
2013
Hetman, C.Moss, S., Webb, K., Hetman, C., Manyumbu, A.Geology of the K1 and K2 kimberlite pipes at Murowa, Zimbabwe.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 35-41.Africa, ZimbabweDeposit - Murowa
DS201501-0014
2015
Hetman, C.Hetman, C.Canadian diamonds: past, present and future.PDAC 2015, 1p. AbstractCanadaHistory
DS201708-1669
2017
Hetman, C.Hetman, C.Letseng diamond mine, Lesotho: a variant of kimberley-type pyroclastic kimberlite emplacement.11th. International Kimberlite Conference, OralAfrica, LesothoDeposit - Letseng

Abstract: The Letšeng Diamond Mine comprises two adjacent kimberlites, the Main and Satellite pipes. Very low grade and low frequency of high value stones preclude use of standard evaluation methods, increasing the need for high confidence geology models. New results of drillcore investigations, including core logging, country rock dilution measurements, indicator mineral abundances and petrography are integrated with open pit mapping and macrodiamond production data to present updated 3D geological models of the Main and Satellite pipes. Letšeng was emplaced ~90 Ma and forms part of a Cretaceous kimberlite province extending across southern Africa. The Letšeng bodies are steep-sided volcanic pipes that are infilled with multiple asymmetric phases of kimberlite separated by near-vertical, sharp, cross-cutting internal contacts. There are associated marginal carbonate-cemented country-rock breccias and sub-vertical kimberlite dykes that can occur within a zone of well-developed carbonate veining adjacent to the pipes. The pipe infills are dominated by kimberlite closely resembling Kimberley-type pyroclastic kimberlite (KPK; formerly tuffisitic kimberlite; Scott Smith et al. 2013) that contains common large megaxenoliths of massive and brecciated country rock basalt. Other textural varieties include hypabyssal kimberlite (HK), transitional HK-KPK and resedimented volcaniclastic kimberlite (RVK). Each phase of kimberlite represents a separate magmatic system. In each KPK there is a continuum of crystallization from the magmaclast selvages to the intermagmaclast matrix. As documented elsewhere, the HK-KPK transition involves an increasing (i) degree of deuteric replacement of olivine, (ii) amount of incorporated country rock xenoliths and (iii) textural modification of the magma prior to solidification subsurface within the diatreme. These conclusions negate some other proposed modes of emplacement.
DS201710-2231
2017
Hetman, C.Hetman, C.Highland Gems: Letseng, Kao, Mothae, Monastery11th International Kimberlite Field Trip Guide, Sept. 59p. PdfAfrica, Lesothodeposit - Letseng, Kao, Mothae, Monastery
DS201809-1993
2018
Hetman, C.Barnett, W., Stubley, M., Hetman, C., Uken, R., Hrkac, C., McCandless, T.Kelvin and Faraday kimberlite emplacement geometries and implications for subterranean magmatic processes.Mineralogy and Petrology, doi.org/10.1007/ s00710-018-0621-8 16p.Canada, Northwest Territoriesdeposit - Kelvin, Faraday

Abstract: The Kennady North Project kimberlites (Northwest Territories of Canada) comprises multiple shallow dipping dykes and several volcaniclastic bodies that have an unusual shallow plunging geometry and complex "pipe" shapes that are termed chonoliths. The detailed exploration of the entire system provides exceptional evidence for subterranean volcanic conduit growth processes. The possible processes leading to the development of the kimberlite bodies are discussed, with emphasis on the importance of the subsurface intrusive system geometry and the local stress tensor. Emplacement into a locally compressive stress regime (i.e. ?1 and ?2 inclined at a low angle to surface) could change the kimberlite emplacement geometries to that observed at Kennady North. Models are proposed for the development of the chonoliths, to emphasize aspects of the growth of kimberlite systems that are not well understood. The conclusions challenge or evolve current emplacement models and should influence kimberlite exploration and resource definition assumptions.
DS202107-1145
2021
Hetman, C.Webb, K., Hetman, C.Magmaclasts in kimberlite.Lithos, Vol. 396-397, 106197 pdfGlobalKimberlite emplacement

Abstract: This contribution presents an updated descriptive scheme for magmaclasts in kimberlite, resulting from over 40 combined years of mapping, logging, and petrographic studies by the authors of hundreds of kimberlites and related rocks globally. Systematic description of the essential characteristics of magmaclasts enables their identification, classification and interpretation. Magmaclasts are fluidal-shaped bodies of kimberlite magma (now solidified) formed by any process of magma disruption prior to solidification. The key characteristics used to discriminate the two main varieties, melt segregations and melt-bearing pyroclasts, are explained and illustrated, as well as the features of melt-bearing pyroclasts in the two main classes of pyroclastic kimberlite. Accurate classification of magmaclasts in coherent and volcaniclastic kimberlites is fundamental for the development of valid geological models in support of exploration, evaluation and mine planning. Magmaclasts are used to determine parental magma type, the textural-genetic classification of the infills of kimberlite bodies, the presence of different eruptive phases (and mixing between them), and the emplacement history of a kimberlite. They can also provide insight on potential modification of the inherent diamond distribution of a kimberlite.
DS200812-0806
2008
Hetman, C.J.Nowicki, T., Hetman, C.J., Gurney, J., Van Collar, B., Galloway, M., Mukodzani, B.Optimizing kimberlite evaluation programs by integrating geological, mineralogical and geophysical data.Northwest Territories Geoscience Office, p. 46-47. abstractTechnologyBrief overview - evaluation
DS1995-1679
1995
Hetman, C.M.Schulze, D.J., Anderson, P.F.N., Hetman, C.M.Origin and significance of ilmenite megacrysts and macrocrysts fromkimberlite.International Geology Review, Vol. 37, No. 9, Sept. pp. 780-812.GlobalKimberlite, Petrology -ilmenite
DS2003-0580
2003
Hetman, C.M.Hetman, C.M., Scott Smith, B.H., Paul, J.L., Winter, F.W.Geology of the Gahcho Kue kimberlite pipes, NWT Canada: root to diatreme transition8th. International Kimberlite Conference Large Core Exhibit volume, 5p.Northwest TerritoriesGeology - description, Deposit - Gahcho Kue
DS2003-0581
2003
Hetman, C.M.Hetman, C.M., Scott Smith, B.H., Paul, J.L., Winter, F.W.Geology of the Gahcho Kue kimberlite pipes, NWT, Canada: root to diatreme8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractNorthwest TerritoriesGeology, economics, Deposit - Gahcho Kue
DS2003-1164
2003
Hetman, C.M.Rikhotso, C.T., Poniatowski, B.T., Hetman, C.M.Overview of the exploration, evaluation and geology of the Gahcho Kue kimberlites8th. International Kimberlite Conference Large Core Exhibit volume, 8p.Northwest TerritoriesGeology - description, Deposit - Gahcho Kue, 5034, Hearne, Tuzo, Tesla
DS2003-1460
2003
Hetman, C.M.Webb, K.J., Scott Smith, B.H., Paul, J.L., Hetman, C.M.Geology of the Victor kimberlite, Attawapiskat, Northern Ontario, Canada: cross8 Ikc Www.venuewest.com/8ikc/program.htm, Session 1, AbstractOntario, James Bay LowlandsGeology, economics, Deposit - Victor
DS200412-0822
2004
Hetman, C.M.Hetman, C.M., Schulze, D.J.The ilmenite association of the Attawapiskat kimberlite cluster, Ontario, Canada.Geological Association of Canada Abstract Volume, May 12-14, SS14-08 p. 267.abstractCanada, Ontario, Attawapiskat, James Bay LowlandsMicroprobe studies, mineral chemistry
DS200412-0823
2003
Hetman, C.M.Hetman, C.M., Scott Smith, B.H., Paul, J.L.,Winter, F.W.Geology of the Gahcho Kue kimberlite pipes, NWT Canada: root to diatreme transition zones.8th. International Kimberlite Conference Large Core Exhibit volume, 5p.Canada, Northwest TerritoriesGeology - description Deposit - Gahcho Kue
DS200412-0824
2003
Hetman, C.M.Hetman, C.M., Scott Smith, B.H., Paul, J.L., Winter, F.W.Geology of the Gahcho Kue kimberlite pipes, NWT, Canada: root to diatreme transition zones.8 IKC Program, Session 1, AbstractCanada, Northwest TerritoriesGeology, economics Deposit - Gahcho Kue
DS200412-1668
2003
Hetman, C.M.Rikhotso, C.T., Poniatowski, B.T., Hetman, C.M.Overview of the exploration, evaluation and geology of the Gahcho Kue kimberlites, Northwest Territories.8th. International Kimberlite Conference Large Core Exhibit volume, 8p.Canada, Northwest TerritoriesGeology - description Deposit - Gahcho Kue, 5034, Hearne, Tuzo, Tesla
DS200412-2092
2003
Hetman, C.M.Webb, K.J., Scott Smith, B.H., Paul, J.L., Hetman, C.M.Geology of the Victor kimberlite, Attawapiskat, Northern Ontario, Canada: cross cutting and nested craters.8 IKC Program, Session 1, AbstractCanada, Ontario, Attawapiskat, James Bay LowlandsGeology, economics Deposit - Victor
DS200612-0575
2006
Hetman, C.M.Hetman, C.M.Tuffisitic kimberlite: a Canadian perspective on a distinctive textural variety of kimberlite.Emplacement Workshop held September, 5p. extended abstractCanadaDeposit - Gahcho Kue, Qilalugaq, Renard, Aviat, Camsell
DS200612-0576
2006
Hetman, C.M.Hetman, C.M., Scott Smith, B.H., Paul, J.L., Winter, F.W.Geology of the Gahcho Kue kimberlite pipes, NWT, Canada: root to diatreme ransition zones.Emplacement Workshop held September, 5p. extended abstractCanada, Northwest TerritoriesDeposit - Gahcho Kue, Tuzo, Hearne
DS200812-0469
2008
Hetman, C.M.Hetman, C.M.Tuffisitic kimberlite ( TK): a Canadian perspective on a distinctive textural variety of kimberlite.Journal of Volcanology and Geothermal Research, Vol. 174, 1-3, pp. 57-67.Canada, Northwest Territories, QuebecTKB, breccia, volcaniclastic, MVK, diatreme,emplacement
DS200812-1032
2008
Hetman, C.M.Scott Smith, B.H., Nowicki, T.E., Russell, J.K., Webb, K.J., Hetman, C.M., Harder, M., Mitchell, R.H.Kimberlites: descriptive geological nomenclature and classification.Northwest Territories Geoscience Office, p. 55. abstractTechnologyBrief overview - nomenclature, classification
DS200812-1244
2008
Hetman, C.M.Webb, K.J., Crawford, B., Nowicki, T.E., Hetman, C.M., Carlson, J.Coherent kimberlite at Ekati, NWT: textural and geochmeical variations and implications for emplacement.Northwest Territories Geoscience Office, p. 74. abstractCanada, Northwest TerritoriesDeposit - Ekati
DS200912-0222
2009
Hetman, C.M.Fitzgerald, C.E., Hetman, C.M., Lepine,I., Skelton, D.S., McCandless, T.E.The internal geology and emplacement history of the Renard 2 kimberlite, Superior Province, Quebec, Canada.Lithos, In press - available 29p.Canada, QuebecDeposit - Renard
DS200912-0279
2009
Hetman, C.M.Harder, M., Scott Smith, B.H., Hetman, C.M., Pell, J.The evolution of geological models for the DO-27 kimberlite, NWT Canada: implications for evaluation.Lithos, In press - available 38p.Canada, Northwest TerritoriesDeposit - DO-27
DS200912-0678
2008
Hetman, C.M.Scott Smith, B.H., Nowicki, T.E., Russell, J.K., Webb, K.J., Hetman, C.M., Harder,M., Mitchell, R.H.Kimberlites: descriptive geological nomenclature and classification POSTER.scottsmithpetrology.com, POSTER free to downloadTechnologyKimberlite classification
DS200912-0796
2009
Hetman, C.M.Verigeanu, D., Hetman, C.M., Jellicoe, B., Baumgartner, M.C.Preliminary geology, mineral chemistry and diamond results from the C29/30 Candle Lake volcanic complex, Saskatchewan, Canada.Lithos, In press - available formatted 12p.Canada, SaskatchewanDeposit - Candle Lake
DS201012-0276
2010
Hetman, C.M.Hetman, C.M., Nowicki, T., Freeman, L., Abedu, B.The preliminary geology and evaluation of the Koidu kimberlite dykes, Sierra Leone.International Dyke Conference Held Feb. 6, India, 1p. AbstractAfrica, Sierra LeoneDyke morphology
DS201212-0298
2012
Hetman, C.M.Hetman, C.M., Freeman, L., Nowicki, T.E., Abedu, B.Internal geology development and emplacement of the K1 kimberlite pipe, Koidu mine, Sierra Leone, West Africa.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractAfrica, Sierra LeoneDeposit - Koidu
DS201212-0629
2012
Hetman, C.M.Scott Smith, B.H., Nowicki, T.E., Russell, J.K., Webb, K.J., Mitchell, R.H., Hetman, C.M., Harder, M., Skinner, E.M.W., Robey, J.V.Kimberlite terminology and classification: geology and emplacement.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractGlobalClassification - kimberlites
DS201212-0765
2012
Hetman, C.M.Webb, K.J., Hetman, C.M., Nowicki, T.E., Harrison, S., Carlson, J., Parson, S., Paul, J.L.The updated model of the Misery kimberlite complex, Ekati mine, Northwest Territories.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractCanada, Northwest TerritoriesDeposit - Misery
DS201312-0363
2013
Hetman, C.M.Harder, M., Nowicki, T.E., Hetman, C.M.Geology and evaluation of the K2 kimberlite, Koidu mine, Sierra Leone, West Africa.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 191-208.Africa, Sierra LeoneDeposit - Koidu
DS201312-0797
2013
Hetman, C.M.Scott Smith, B.H., Nowicki, T.E., Russell, J.K., Webb, K.J., Mitchell, R.H., Hetman, C.M., Harder, M., Skinner, E.M.W., Robey, Jv.A.Kimberlite terminology and classification.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, Special Issue of the Journal of the Geological Society of India,, Vol. 2, pp. 1-17.TechnologyTerminology
DS201412-0339
2013
Hetman, C.M.Harder, M., Nowicki, T.E., Hetman, C.M., Freeman, L., Abedu, B.Geology and exploration of the K2 kimberlite, Koidu mine, Sierra Leone, West Africa.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 191-208.Africa, Sierra LeoneDeposit - Koidu (K2)
DS201412-0354
2014
Hetman, C.M.Hetman, C.M.Kimberlite geology: the foundation of your resource.SRK and Friends Diamond Short Course, March 1, ppt p. 67-79.TechnologyResource model
DS201412-0790
2013
Hetman, C.M.Scott Smith, B.H., Nowicki, T.E., Russell, J.K., Webb, K.J., Mitchell, R.H., Hetman, C.M., Harder, M., Skinner, E.M.W., Robey, Jv.A.Kimberlite terminology and classification.Proceedings of the 10th. International Kimberlite Conference, Vol. 2, pp. 1-18.Classification
DS201712-2675
2017
Hetman, C.M.Barnett, W., Stubley, M., Hrkac, C., Hetman, C.M., McCandless, T.Kelvin and Faraday kimberlite emplacement geometries and implications for subterranean magmatic processes.45th. Annual Yellowknife Geoscience Forum, p. 4 abstractCanada, Northwest Territoriesdeposit - Kelvin, Faraday

Abstract: The Kennady North Project kimberlites are located approximately 280 kilometers east-northeast of Yellowknife, in the Northwest Territories of Canada. The unusual geometry and extent of the kimberlite magmatic system is revealed by renewed exploration drilling activities by Kennady Diamonds since 2012. It has become clear that the system comprises multiple intrusive dykes within which several volcaniclastic bodies have developed, all within 11 kilometres of the Gahcho Kué kimberlite cluster and diamond mine. The detailed exploration of the entire system provides unique evidence for subterranean volcanic conduit growth processes that may have scientific and practical exploration benefits. The identified Kennady North Project volcaniclastic bodies are named Kelvin, Faraday 1, Faraday 2 and Faraday 3, and have complex geometries atypical of the more common subvertical kimberlite pipes. Rather, these pipe-like bodies are inclined between 12 and 30 degrees towards the northwest. Kelvin has sharp angular change in trend towards the north. On-going detailed petrographic studies have shown that the pipes contain layers of complex volcaniclastic units with variable volumes of xenolithic fragments, as well as coherent magmatic layers. The pipe textures include evidence for high energy magma and country rock fragmentation processes typically observed in open volcanic systems. The pipes have developed within a shallow 20 degree northwest dipping kimberlite dyke system. Detailed structural geology studies, using fault observations in oriented and unoriented drill core, have identified at least two important fault-fracture trends. The first fault-fracture system is parallel to the dyke segments, and likely related to the intrusion of the dykes and the regional stress tensor during emplacement. The second fault system is subvertical and north-south striking, parallel to the lithological layering within the metasedimentary country rock. The north-south faults match the contact geometry of the Kelvin pipe’s north-south limb exactly. The dykes have been 3-D modelled along with the pipes. Three possible renditions of the dykes have been created, based on different interpretations of dyke segment continuity. The renditions have been labelled “Optimistic”, “Realistic” and “Pessimistic”. The assumptions made have important implications for developing dyke-type mineral resources. The realistic dyke model defines dyke segments that intersect the Kelvin pipe, and those intersections match geometric trends and irregularities in the pipe shape. The coincidental geometries strongly imply that the pipe development interacted with a penecontemporaneous dyke system. The north-south faults also controlled the local trend of Kelvin pipe development, possibly by enhancing fluid permeability, alteration and brecciation along the faults, connecting from one shallow dipping dyke to the next above. Breccia bodies have been observed on similar dipping dykes at Snap Lake mine that intersect fault structures. We conclude that the pipe development geometry and process is governed by a combination of stress, structure and magmatic fluids, and speculate on the nature of the energy required for fragmentation and development of the pipe at some still unknown depth in the crust.
DS201712-2709
2017
Hetman, C.M.Nelson, L., Hetman, C.M., Diering, M.The geology of the Faraday 2 kimberlite pipe, Northwest Territories.45th. Annual Yellowknife Geoscience Forum, p. 106 abstract posterCanada, Northwest Territoriesdeposit - Faraday 2
DS201810-2296
2018
Hetman, C.M.Bezzola, M., Hetman, C.M., Garlick, G., Creaser, R., Diering, M., Nowicki, T.Geology and resource development of the Kelvin kimberlite pipe, Northwest Territories, Canada.Mineralogy and Petrology, doi.org/10.1007/s00710-018-0631-6 13p.Canada, Northwest Territoriesdeposit - Kelvin

Abstract: The early Cambrian to late Neoproterozoic Kelvin kimberlite pipe is located in the southeast of the Archean Slave Craton in northern Canada, eight km northeast of the Gahcho Kué diamond mine. Kelvin was first discovered in 2000 by De Beers Canada. Subsequent exploration undertaken by Kennady Diamonds Inc. between 2012 and 2016 resulted in the discovery of significant thicknesses of volcaniclastic kimberlite that had not previously been observed. Through extensive delineation drilling Kelvin has been shown to present an atypical, steep-sided inclined L-shaped pipe-like morphology with an overall dip of 15 to 20°. With a surface expression of only 0.08 ha Kelvin dips towards the northwest before turning north. The body (which remains open at depth) has been constrained to a current overall strike length of 700 m with varying vertical thickness (70 to 200 m) and width (30 to 70 m). Detailed core logging, petrography and microdiamond analysis have shown that the pipe infill comprises several phases of sub-horizontally oriented kimberlite (KIMB1, KIMB2, KIMB3, KIMB4, KIMB7 and KIMB8) resulting from multiple emplacement events. The pipe infill is dominated by Kimberley-type pyroclastic kimberlite or “KPK”, historically referred to as tuffisitic kimberlite breccia or “TKB”, with less common hypabyssal kimberlite (HK) and minor units with textures transitional between these end-members. An extensive HK sheet complex surrounds the pipe. The emplacement of Kelvin is believed to have been initiated by intrusion of this early sheet system. The main pipe-forming event and formation of the dominant KPK pipe infill, KIMB3, was followed by late stage emplacement of additional minor KPK and a hypabyssal to transitional-textured phase along the upper contact of the pipe, cross-cutting the underlying KIMB3. Rb-Sr age dating of phlogopite from a late stage phase has established model ages of 531 ± 8 Ma and 546 ± 8 Ma. Texturally and mineralogically, the Kelvin kimberlite is similar to other KPK systems such as the Gahcho Kué kimberlites and many southern African kimberlites; however, the external morphology, specifically the sub-horizontal inclination of the pipe, is unique. The morphology of Kelvin and the other kimberlites in the Kelvin-Faraday cluster defines a new type of exploration target, one that is likely not unique to the Kennady North Project area. Extensive evaluation work by Kennady Diamonds Inc. has resulted in definition of a maiden Indicated Mineral Resource for Kelvin of 8.5 million tonnes (Mt) of kimberlite at an average grade of 1.6 carats per tonne (cpt) with an average diamond value of US$ 63 per carat (ct).
DS201212-0284
2012
Hetman, T.E.Harder, M.C., Nowickia, C., Hetman, T.E., Hetmana, D., Freeman, C.M., Abedub, B.Geology and evaluation of the K2 kimberlite, Koidu mine, Sierra Leone, West Africa.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractAfrica, Sierra LeoneDeposit - K2 Koidu
DS201212-0284
2012
Hetmana, D.Harder, M.C., Nowickia, C., Hetman, T.E., Hetmana, D., Freeman, C.M., Abedub, B.Geology and evaluation of the K2 kimberlite, Koidu mine, Sierra Leone, West Africa.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractAfrica, Sierra LeoneDeposit - K2 Koidu
DS2001-1110
2001
HettelSperner, B., Lorenz, F., Hettel, Muller, B., Wenzel, F.Slab break off abrupt cut or gradual detachment? New insights from Vrancea region (southeast Carpathians).Terra Nova, Vol. 13, pp. 172-79.RomaniaSubduction - slab, Tectonics
DS1992-0195
1992
Hettich, R.Buseck, P.R., Tsipursky, S.J., Hettich, R.Fullerenes from the geological environmentScience, Vol. 257, July 10, pp. 215-217GlobalFullerenes -natural, Carbon
DS201811-2581
2013
Hettihewa, S.Iddon, C., Hettihewa, S., Wright, C.S.Junior mining sector capital raising: the effects of information asymmetry and uncertainty issues.Journal of Applied Business and Economics, Vol. 15, 3, 12p. PdfGlobaleconomics

Abstract: While prospecting by junior mining companies (JMCs) is a vital contributor to modern wealth creation, attributes of the junior mining sector (JMS) limit JMC-fund raisings to external equity (shares). In considering responses by JMC principals to deep discounting and other JMC-investor strategies, potential responses were found to: increase returns to principals, increase JMS moral-hazard issues, and further deepen price discounts on JMC share offerings, especially IPOs. It is suggested that the attractiveness and moral-hazard consequences of these potential responses can be greatly diminished if mining-tenement fees are raised and JMC prospecting costs are allowed as an offset against those fees.
DS1987-0291
1987
Hettinger, R.D.Hettinger, R.D., Bankey, V., Causey, J.D.Mineral resources of the Burnt Lodge wilderness study area,Phillips and Valley Counties, MontanaGeological Survey Bulletin. (Washington), pp. A1-16MontanaDiamonds mentioned
DS201112-0266
2011
Hettmann, K.Derrey, I., Hettmann, K., Thaler, F., Wenzel, T., Marks, M., Markl, G.Sulfur content and speciation in sodalite and its possible use as redox proxy.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologySodalite
DS201112-0433
2011
Hettmann, K.Hettmann, K., Marks, M., Kressing, K., Zack, T., Wenzel, T., Rehkamper, M., Jacob, D., Markl, G.The geochemistry of thallium and its isotopes in a peralkaline magmatic system.Peralk-Carb 2011, workshop held Tubingen Germany June 16-18, PosterTechnologyMagmatism
DS201112-0645
2011
Hettmann, K.Marks, M.A.W., Hettmann, K., Schilling, J., Frost, B.R., Markl, G.The mineralogical diversity of alkaline igneous rocks: critical factors for the transition from miaskitic to agpaitic phase assemblages.Journal of Petrology, Vol. 52, 3, pp. 439-455.Alkalic
DS1989-0630
1989
Hetu, R.Hetu, R.Lup in mine area, Northwest Territories 1988- airborne gamma ray spectrometric black and white contour mapsG.s.c. Open File, No. 1921, 1: 50, 000 $ 40.50Northwest TerritoriesGeophysics, Gold, Deposit - Lupin
DS1989-0631
1989
Hetu, R.Hetu, R.Kimberlite test study, Saskatchewan, 1989: airborne gamma ray spectrometer surveyG.s.c. Open File, No. 2128, 1: 50, 000 scale 48 stacked profiles $31.50SaskatchewanGeophysics, Kimberlite -gamma ray spe
DS1994-0284
1994
Hetu, R.J.Charbonneau, B.W., Holman, P.B., Hetu, R.J.Airborne geophysical survey, northeast AlbertaGeological Survey of Canada Open File, No. 2807, 13 maps $ 195.00AlbertaGeophysics
DS1999-0305
1999
Hetzel, R.Hetzel, R.Geology and geodynamic evolution of the high pressure/ low temperature Maksyutov Complex, southern Urals, Russia.Geologische Rundschau, Vol. 87, No. 4, pp. 577-88.Russia, UralsComplex - Maksyutov, Geodynamics, eclogite, metamorphic
DS2000-0114
2000
Hetzel, R.Brown, D., Hetzel, R., Scarrow, J.H.Tracking arch ... continent collision subduction zone processes from high pressure rocks in southern UralsJournal of Geological Society of London, Vol. 157, No. 5, Sept.pp. 901-4.Russia, UralsMetamorphism - ultra high pressure (UHP)
DS200712-0116
2006
Hetzel, R.Brown, D., Spadea, P., Puchkov, V., Alvarez-Marron, J., Herrington, R., Willner, A.P., Hetzel, R., Gorozhanina, Y., Juhlin, C.Arc continent collision in the southern Urals.Earth Science Reviews, in press availableRussia, UralsBaltica tectonics, UHP, geochemistry
DS200712-0210
2007
Hetzel, R.Currie, A., Hetzel, R., Densmore, A.L.The fate of subducted sediments: a case for backarc intrusion and underplating.Geology, Vol. 35, 12 Dec. pp. 1111-1114.MantleSubduction
DS1994-0766
1994
Heubeck, C.Heubeck, C., Lowe, D.R.Depositional and tectonic setting of the Archean Moodies Group, Barberton greenstone belt, South AfricaPrecambrian Research, Vol. 68, No. 3-4, August pp. 257-290South AfricaGreenstone belt -Barberton, Tectonics
DS1994-0767
1994
Heubeck, C.Heubeck, C., Lowe, D.R.Late syndepositional deformation and detachment tectonics in the Barberton greenstone belt, South AfricaTectonics, Vol. 13, No. 6, Dec. pp. 1514-1536South AfricaTectonics, Barberton greenstone belt
DS1860-0145
1871
Heubner, A.Heubner, A.Gesteine im Den Diamant fuehrenden Gegenden des Vaalthals Insuedafrika.Neues Jahrbuch f?r Mineralogie, PP. 767-768.Africa, South AfricaHistory
DS202104-0589
2021
Heuer, V.B.Lollar, B.S., Heuer, V.B., McDermott, J., Tille, S., Warr, O., Moran, J.J., Telling, J., Hinrichs, K-U.A window into the abiotic carbon cycle - acetate and formate in fracture waters in 2.7 billion year-old host rocks of the Canadian shield. ( Not specific to diamonds just interest)Geochimica et Cosmochimica Acta, Vol. 294. pp. 295-314. pdfCanadacarbon

Abstract: The recent expansion of studies at hydrothermal submarine vents from investigation of abiotic methane formation to include abiotic production of organics such acetate and formate, and rising interest in processes of abiotic organic synthesis on the ocean-world moons of Saturn and Jupiter, have raised interest in potential Earth analogs for investigation of prebiotic/abiotic processes to an unprecedented level. The deep continental subsurface provides an attractive target to identify analog environments where the influence of abiotic carbon cycling may be investigated, particularly in hydrogeological isolated fracture fluids where the products of chemical water-rock reactions have been less overprinted by the biogeochemical signatures of the planet’s surficial water and carbon cycles. Here we report, for the first time, a comprehensive set of concentration measurements and isotopic signatures for acetate and formate, as well as the dissolved inorganic and organic carbon pools, for saline fracture waters naturally flowing 2.4?km below surface in 2.7 billion year-old rocks on the Canadian Shield. These geologically ancient fluids at the Kidd Creek Observatory were the focus of previous investigations of fracture fluid geochemistry, microbiology and noble gas-derived residence times. Here we show the fracture waters of Kidd Creek contain high concentrations of both acetate and formate with concentrations from 1200 to 1900?µmol/L, and 480 to 1000?µmol/L, respectively. Acetate and formate alone account for more than 50-90% of the total DOC - providing a very simple "organic soup". The unusually elevated concentrations and profoundly 13C-enriched nature of the acetate and formate suggest an important role for abiotic organic synthesis in the deep carbon cycle at this hydrogeologically isolated site. A variety of potential abiotic production reactions are discussed, including a radiolytically driven H, S and C deep cycle that could provide a mechanism for sustaining deep subsurface habitability. Scientific discoveries are beginning to reveal that organic-producing reactions that would have prevailed on Earth before the rise of life, and that may persist today on planets and moons such as Enceladus, Europa and Titan, can be accessed in some specialized geologic settings on Earth that provide valuable natural analog environments for the investigation of abiotic organic chemistry outside the laboratory.
DS200512-0430
2005
Heuret, A.Heuret, A., Lallemand, S.Plate motions, slab dynamics and back arc deformation.Physics of the Earth and Planetary Interiors, Vol. 149, 1-2, March 15, pp. 31-51.MantleSubduction
DS200512-0596
2005
Heuret, A.Lallemand, S., Heuret, A., Boutelier, D.On the relationship between slab dip, back arc stress, upper plate absolute motion, and crustal nature in subduction zones.Geochemistry, Geophysics, Geosystems: G3, Vol. 6, Q12J14, doi:10.1029/2005 GC000917MantleSubduction, geodynamics
DS200812-0373
2008
Heuret, A.Funiciello, F., Faccenna, C., Heuret, A., Lallemand, S., Di Guiseppe, E., Becker, T.W.Trench migration, net rotation and slab mantle decoupling.Earth and Planetary Science Letters, Vol. 271, 1-4, pp. 233-240.MantleSubduction
DS200812-0628
2008
Heuret, A.Lallemand, S., Heuret, A., Faccenna, C., Funiciello, F.Subduction dynamics as revealed by trench migration.Tectonics, Vol. 27, TC3014MantleSubduction
DS200812-1271
2008
Heuret, A.Wu, B., Conrad, C.P., Heuret, A., Lithgow Bertollini, C., Lallemand, S.Reconciling strong slab pull and weak plate bending: the plate motion constraint on the strength of mantle slabs.Earth and Planetary Science Letters, Vol. 272, 1-2, pp. 412-421.MantleSubduction
DS200812-1273
2008
Heuret, A.Wu, C., Conrad, C.P., Heuret, A., Lithgow-Bertelloni, C., Lallemand, S.Reconciling strong slab pull and weak plate bending: the plate motion constraint on the strength of mantle slabs.Earth and Planetary Science Letters, Vol. 272, 1-2, July 30, pp. 412-421.MantleSubduction
DS1993-0664
1993
Heuschmidt, B.Heuschmidt, B., Miranda, R.M., Velarde, J.A.Summary of geological history of Bolivia - precambrian shield, Cordillera Paleozoic belt, Altiplano and western Cordiller volcanic belt, northernpiedmontBolinwest/Carana publication, 135p. approx. $ 20.00BoliviaGeology, Regional overviews
DS1859-0132
1859
Heusser, C.G.Heusser, C.G.Ueber die Wahre Lagerstatte der Diamanten und Anderer Edelsteine in der Provinz Minas Geraes in Brasilien.Zeitschrift Der Deutschen Geol. Gesellschaft., BD. 11, PP. 448-466.BrazilDiamonds
DS1996-1198
1996
Heusser, E.Rochell, A., Heusser, E., Kirsten, T., Oehm, J., RichterA noble gas profile across a Hawaiian mantle xenolith: coexisting accidental and cognate noble gases derivedGeochimica et Cosmochimica Acta, Vol. 60, No. 23, pp. 4773-83.Mantle, HawaiiGeochemistry - ultramafic xenoliths, Geochronology
DS1980-0173
1980
Heusser, G.Heusser, G.Hunting Cape May DiamondsLapidary Journal, Vol. 34, No. 7, PP. 1538-1539.United States, Appalachia, New YorkHerkimer Diamonds
DS200512-0988
2005
Hewett, J.Simandl, G.J., Davis, W., Hewett, J.Precambrian basement - NE British Columbia - new Pb geochronological dat a and their significance for diamond exploration.British Columbia Mines, 2005-12, Canada, British ColumbiaGeochronology
DS200512-0989
2005
Hewett, T.Simandl, G.J., Ferbey, T., Levson, V.M., Demchuk, T.E., Hewett, T., Smith, I.R.,KjarsgaardHeavy mineral survey and its significance for diamond exploration, Fort Nelson area, BC.British Columbia Mines, 2005-13, Canada, British ColumbiaGeochemistry - KIM
DS1970-0693
1973
Hewins, R.H.Gittins, J., Hewins, R.H., Laurin, A.F.Kimberlitic Carbonatitic Dikes of the Saguenay River ValleyProceedings of First International Kimberlite Conference, EXTENDED ABSTRACT PP. 127-130.Canada, QuebecOccurrences
DS1975-0085
1975
Hewins, R.H.Gittins, J., Hewins, R.H., Laurin, A.F.Kimberlitic and Carbonatitic Dykes of the Saguenay River Valley, Quebec, Canada.Physics and Chemistry of the Earth., Vol. 9, PP. 137-148.Canada, QuebecRelated Rocks, Carbonatite, Kimberlite, Arvida
DS200912-0298
2009
Hewitt, L.J.Hewitt, L.J., Fowler, A.F.Melt characterization in ascending mantle.Journal of Geophysical Research, Vol. 114, B06210.MantleMagma flow, melting
DS1995-1874
1995
Hey, R.Taylor, B., Goodliffe, A., Martinez, F., Hey, R.Continental rifting and initial sea floor spreading in the Woodlark BasinNature, Vol. 374, No. 6522, April 6, p. 534-536.GlobalTectonics, Rifting
DS1995-1875
1995
Hey, R.Taylor, B., Goodliffe, A., Martinez, F., Hey, R.Continental rifting and initial sea floor spreading in the Woodlark BasinNature, Vol. 374, April 6, pp. 534-537Papua New Guinea, Solomon IslandsTectonics, Rifting
DS1998-0617
1998
Hey, R.N.Hey, R.N.Speculative propogating rift subduction zone interactions with possible consequences for margin...Geology, Vol. 26, No. 3, March pp. 247-250.CaliforniaContinental margin evolution, Subduction
DS201212-0212
2012
Heyde, I.Funck, T., Gohl, K., Damm, V., Heyde, I.Tectonic evolution of southern Baffin Bay and Davis Strait: results from a seismic refraction transect between Canada and Greenland.Journal of Geophysical Research, Vol. 117, B04107, 24p.Canada, Nunavut, Baffin Island, Europe, GreenlandGeophysics - seismics
DS201212-0711
2012
Heyde, I.Suckro, S.K., Gohl, K., Funck, T., Heyde, I., Ehrardt, A., Schreckenberger, B., Gerlings, J., Damm, V., Jokat, W.The crustal structure of southern Baffin Bay: implications from a seismic refraction experiment.Geophysical Journal International, Vol. 190, 1, pp. 37-58.Canada, Nunavut, Baffin Island, Europe, GreenlandGeophysics - seismics
DS1960-0153
1961
Heyl, A.V.Heyl, A.V., Brock, M.R.Structural Framework of the Illinois Kentucky Mining District and its Relation to Mineral Deposits.United States Geological Survey (USGS) PROF. PAPER., No. 424-D, PP. D3-D6.United States, Kentucky, AppalachiaTectonics, Structure, Regional Geology
DS1960-0256
1962
Heyl, A.V.Kiilsgaard, T.H., Heyl, A.V., Brock, M.R.The Crooked Creek Disturbance Southeast MissouriUnited States Geological Survey (USGS) PROF. PAPER., No. 450-E, PP. E14-E19.Missouri, United States, Central StatesCryptoexplosion
DS1960-0558
1965
Heyl, A.V.Heyl, A.V., Brock, M., Jolly, J.L., Wells, G.E.Regional Structure of Southeast Missouri and Illinois- Kentucky Mineral District.United States Geological Survey (USGS) Bulletin., No. 1202-B, 20P.United States, Kentucky, Missouri, Illinois, Central StatesBlank
DS1960-0559
1965
Heyl, A.V.Heyl, A.V., Brock, M.R., Jolly, J.L., Wells, C.E.Regional Structure of the Southeast Missouri and Illinois Kentucky Mineral Districts.United States Geological Survey (USGS) Bulletin., No. 1202-B, 20P.GlobalMid Continent
DS1960-0899
1967
Heyl, A.V.Zartman, R.E., Brock, M.E., Heyl, A.V., Thomas, H.H.Potassium-argon and Rubidium-strontium Ages of Some Alkaline Intrusive rocks from Central and Eastern United States.American Journal of Science, VOL 265, PP. 838-870.United States, Appalachia, New York, Central StatesGeology, Related Rocks, Kimberlite, Geochronology
DS1970-0533
1972
Heyl, A.V.Heyl, A.V.The 38th Parallel Lineament and its Relationship to Ore Deposits.Economic Geology, Vol. 67, PP. 879-894.GlobalMid-continent
DS1981-0243
1981
Heyl, A.V.Kisvarsanyi, E.B., Pratt, W.P., Heyl, A.V.Fluorine-thorium Rare Earth Bearing Kimberlite Carbonatite ComplexesUnited States Geological Survey (USGS) OPEN FILE REPORT., No. 81-0518, PP. 35-40.Missouri, United States, Central StatesBlank
DS1983-0302
1983
Heyl, A.V.Heyl, A.V.Some Major Lineaments Reflecting Deep Seated Fracture Zones in the Central United States and Mineral Districts Related To the Zones.Global Tectonics And Metallogeny, Vol. 2, No. 1-2, PP. 75-89.GlobalMid Continent
DS1984-0196
1984
Heyl, A.V.Collins, D.S., Heyl, A.V.History of the Colorado Wyoming State Line DiatremesRocks And Minerals, Vol. 59, No. 1, PP. 35-37.United States, State Line, Colorado, Wyoming, Rocky MountainsHistory
DS1986-0362
1986
Heyl, A.V.Heyl, A.V., Brock, M.R., Jolly, J.L.Phanerozoic igneous rocks, including kimberlites of the United States craton west of the Blue Ridge Mountains and east of the Rocky Mountains and their associated7th. IAGOD Symposium abstract volume, Held August 18-22, Lulea Sweden, pp. 407-408. (abstract.)Colorado, New Mexico, Wyoming, Montana, South DakotaBlank
DS1988-0303
1988
Heyl, A.V.Heyl, A.V., Brock, M.R., Jolly, J.L.Phanerozoic igneous rocks, including kimberlites of the United States craton west of the Blue Ridge Mtns. &east of the Rocky Mountains and their Association mineral deposI.a.g.o.d., Proceedings Of The Seventh Quadrennial Iagod Symposium, Vol. 7, pp. 103-110Arkansas, Tennessee, Kentucky, Illinois, Appalachia, MidcontinentMontana, South Dakota, Colorado, Wyoming, Tectonics
DS1991-0710
1991
Heyl, A.V.Heyl, A.V., Brock, M.R.Mineral deposits related to Proterozoic alkalic igneous rocks of the central part of the United StatesGlobal Tectonics and Metallogeny, Vol. 4, No. 1, 2 September pp. 61-64. extended abstractMissouri, Arkansas, Tennessee, Wyoming, State LineAlkaline rocks, Proterozoic
DS1960-0128
1961
Heyl, A.V.Jr.Brock, M.R., Heyl, A.V.Jr.Post Cambrian Igneous Rocks of the Central Craton, Western Appalachian Mountains and Gulf Coastal Plain of the United States.United States Geological Survey (USGS) PROF. PAPER., No. 424-D, PP. D33-35.United States, Appalachia, New YorkRegional Geology
DS1985-0284
1985
Heylmun, E.B.Heylmun, E.B.Diamonds Near Oroville, CaliforniaCalifornia Mining Journal, Vol. 55, No. 4, December p. 63CaliforniaHistory, News Item
DS1993-0665
1993
Heylmun, E.B.Heylmun, E.B.Kimberlites in the Colorado PlateauCalifornia Mining Journal, July pp. 19-22Colorado, WyomingLayman's overview for rockhounds
DS1987-0292
1987
Heymann, D.Heymann, D.Raman spectra of carbon in the Canyon Diablo iron meteoriteLpi, 18th. Lunar And Planetary Conference, Vol. 28, pt. 2, pp. 419-420GlobalMeteorite
DS1989-0632
1989
Heymann, D.Heymann, D.Is the width of the Raman line of diamond diagnostic for the origin Of diamonds in meteorites - comment on Raman spectra of Ureilite diamondsGeochim. et Cosmochim Acta, Vol. 53, No. 11, pp. 3059-3060GlobalMeteorite, Diamonds
DS1994-0768
1994
Heymann, D.Heymann, D., et al.Fullerenes in the Cretaceous-Tertiary boundary layerScience, Vol. 265, July 29, pp. 645-647.MantleBoundary, Fullerenes, carbon
DS2000-0391
2000
Heymann, D.Harris, P.J.F., Vis, R.D., Heymann, D.Fullerene like carbon nanostructures in the Allende meteoriteEarth and Planetary Science Letters, Vol.183, No.3-4, pp.355-59.GlobalMeteorite, Fullerene
DS202007-1146
2020
Heyn. B.H.Heyn. B.H., Conrad, C.P., Tronnes, R.G.Core-mantle boundary topography and its relation to the viscosity structure of the lowermost mantle.Earth and Planetary Science Letters, Vol. 543, 116358 14p. PdfMantlemantle plumes

Abstract: Two large areas of anomalously low seismic velocities are visible in all tomographic models of the lowermost mantle. Depending on the density structure of these Large Low Shear Velocity Provinces (LLSVPs), the core-mantle boundary (CMB) will deform upwards or downwards due to isostatic and dynamic topography, the latter being sensitive to the viscosity structure of the lowermost mantle. Heterogeneities in the viscosity structure, although difficult to constrain, might be especially important if the LLSVPs are thermochemical piles with elevated intrinsic viscosity as suggested by mineral physics. Based on numerical models, we identify a short-wavelength (about 80-120 km wide, up to a few km deep) topographic depression that forms around the pile edges if the pile is more viscous than the surrounding mantle. The depression forms when a wedge of thermal boundary layer material becomes compressed against the viscous pile, and is enhanced by relative uplift of the CMB beneath the pile by plumes rising above it. The depth and asymmetry of the depression constrain the magnitude of the viscosity contrast between pile and the surrounding mantle. Furthermore, (periodic) plume initiation and pile collapse at the pile margin systematically modify the characteristic depression, with a maximum in asymmetry and depth at the time of plume initiation. Core-reflected waves or scattered energy may be used to detect this topographic signature of stiff thermochemical piles at the base of the mantle.
DS1859-0024
1814
HeyneHeyneMines of IndiaUnknown, IndiaDiamond Occurrence
DS200412-0709
2004
Heyraud, C.Grant, I.F., Heyraud, C., Breon, F-M.Continentral scale hotspot observations of Australia at sub-degree anular resolution from POLDER.International Journal of Remote Sensing, Vol. 25, 18, Sept. pp. 3625-36.AustraliaGeophysics - remote sensing
DS201112-0985
2011
Hezarkhani, A.Soltani, S., Hezarkhani, A.Determination of realistic and statistical value of the information gathered from exploratory drilling.Natural Resources Research, in press available, 8p.TechnologyGeostatistics - not specific to diamonds
DS201312-0384
2013
Hezel, D.C.Hezel, D.C., Friedrich, J., Uesugi, M.Looking inside 3D structures of meteorites.Geochimica et Cosmochimica Acta, Vol. 116, pp. 1-4.TechnologyTomography
DS200712-0601
2007
HHHarris, J.W.Lazarov, M., Brey, G.P., HHHarris, J.W., Weyer, S.Timing of mantle depletion and enrichment from single subcalcic garnet grains (Finsch mine, SA).Plates, Plumes, and Paradigms, 1p. abstract p. A551.Africa, South AfricaFinsch
DS1995-1656
1995
Hibbard, J.P.Samson, S.D., Hibbard, J.P., Wortman, G.L.neodymium isotopic evidence for juvenile crust in the Carolin a Terrane, southernAppalachiansContributions to Mineralogy and Petrology, Vol. 121, No. 2, pp. 171-184Appalachia, CarolinasGeochronology, Tectonics
DS200612-0577
2006
Hibbard, J.P.Hibbard, J.P., Van Staal, C.R., Rankin, D.W., Williams, H.Lithotectonic map of the Appalachian orogen, Canada-United States of America.Geological Survey of Canada, Map 2096A 1: 1,500,000 $ 30.00Canada, United StatesMap - tectonics
DS1992-0221
1992
Hibbard, M.J.Carr, J.R., Hibbard, M.J.Open ended mineralogical/textural rock classificationComputers and Geosciences, Vol. 17, No. 10, pp. 1409-1464GlobalMineralogical classification, Rock classification, Rock and mineral general texture
DS1994-0769
1994
Hibbard, M.J.Hibbard, M.J.Petrographic classification of crystal morphologyJournal of Geology, Vol. 102, pp. 571-81.GlobalCrystal - morphology not specific to diamonds
DS1991-1428
1991
Hibberson, W.Ringwood, A.E., Hibberson, W.Solubilities of mantle oxides in molten iron at high pressures andtemperatures: implications for the composition and formation of earth's coreEarth and Planetary Science Letters, Vol. 102, No. 3/4, Marchpp. 235-251GlobalMantle, Geochemistry
DS1992-1278
1992
Hibberson, W.Ringwood, A.E., Kesson, S.E., Hibberson, W., Ware, N.Origin of kimberlites and related magmas #2Earth and Planetary Science Letters, Vol. 113, No. 4, November pp. 521-538.GlobalKimberlite genesis
DS1992-1279
1992
Hibberson, W.Ringwood, A.E., Kesson, S.E., Hibberson, W., Ware, N.Transition zone source region for kimberlitesEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.325MantleModel, Experimental petrology
DS1997-0332
1997
Hibberson, W.Falloon, T.J., Green, D.H., O'Neill, H., Hibberson, W.Experimental tests of low degree peridotite partial melt compositions:implications for the nature ....Earth and Plan. Sci. Letters, Vol. 152, No. 1-4, pp. 149-162.GlobalPetrology - experimental, Andesitic melts, lherzolites
DS1997-0594
1997
Hibberson, W.Kesson, S., Ringwood, A.E., Hibberson, W., Fit Gerald, J.Reaction between magnesiowustite of lower mantle composition and core-forming alloy at 1-40 GPa.American Mineralogist, Vol. 82, No. 5-6, May-June pp. 526-533.MantleCore, History of earth
DS1986-0383
1986
Hibberson, W.O.Irifune, T., Hibberson, W.O., Ringwood, A.E.Eclogite-garnetite transformations in basaltic and pyrolitic compositions at high pressure and high temperatureProceedings of the Fourth International Kimberlite Conference, Held Perth, Australia, No. 16, pp. 259-261GlobalBlank
DS1986-0385
1986
Hibberson, W.O.Irifune, T., Selkine, T., Ringwood, A.E., Hibberson, W.O.The eclogite garnetite transformation at high pressure and some geophysicalimplicationsEarth and Planetary Science Letters, Vol. 77, pp. 245-256GlobalEclogite
DS1986-0670
1986
Hibberson, W.O.Ringwood, A.E., Hibberson, W.O.high pressure transformation of eclogite to garnetite in sub-ducted oceanic crustNature, Vol. 319, No. 6054, Feb. 13, pp. 584-585GlobalEclogite
DS1989-0683
1989
Hibberson, W.O.Irifune, T., Hibberson, W.O., Ringwood, A.E.Eclogite-garnetite transformation at high pressure and its bearing on The occurrence of garnet inclusions indiamondGeological Society of Australia Inc. Blackwell Scientific Publishing, Special, No. 14, Vol. 2, pp. 877-882GlobalExperimental petrology, Garnet inclusions
DS1994-0900
1994
Hibberson, W.O.Kesson, S.E., Ringwood, A.E., Hibberson, W.O.Kimberlite melting relations revisitedEarth and Planetary Science Letters, Vol. 121, No. 3-4, February pp. 261-262.AustraliaMelt
DS200412-0713
2004
Hibberson, W.O.Green, D.H., Schmidt, M.W., Hibberson, W.O.Island arc ankaramites: primitive melts from fluxed refractory lherzolitic mantle.Journal of Petrology, Vol. 45, 2, pp. 391-403.MantlePetrology
DS200412-1759
2004
Hibberson, W.O.Schmidt, T., Green, D.H., Hibberson, W.O.Ultra calcic magmas generated from Ca depleted mantle: an experimental study on the origin of ankaramites.Journal of Petrology, Vol. 45, 3, pp. 531-554.MantleMagmatism, melt inclusions - not specific to diamonds
DS200812-0429
2008
Hibberson, W.O.Green, D.H., Hibberson, W.O., O'Neill, H.St.C.Clarification of the influence of water on mantle wedge melting.Goldschmidt Conference 2008, Abstract p.A325.MantleMelting
DS201212-0379
2012
Hibberson, W.O.Kovacs, I., Green, D.H., Rosenthal, A., Hermann, J., St.O'Neill, H., Hibberson, W.O., Udvardi, B.An experimental study of water in nominally anhydrous minerals in the upper mantle near the water saturated solidus.Journal of Petrology, Vol. 53, 10, pp. 2067-2093.MantleWater content
DS201212-0598
2012
Hibberson, W.O.Rosenthal, A., Green, D.H., Kovacs, I., Hibberson, W.O., Yaxley, G.M., Brink, F.Experimental study of the role of water in the uppermost mantle.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleWater
DS201412-0312
2014
Hibberson, W.O.Green, D.H., Hibberson, W.O., Rosenthal, A., Kovasc, I., Yaxley, G.M., Falloon, T.J., Brink, F.Experimental study of the influence of water on melting and phase assemblages in the upper mantle.Journal of Petrology, Vol. 55, 10, pp. 2067-2096.MantleMelting
DS201703-0407
2017
Hibiya, Y.Iizuka, T., Yamaguchi, T., Itano, K., Hibiya, Y., Suzuki, K.What Hf isotopes in zircon tell us about crust mantle evolution.Lithos, Vol. 274-275, pp. 304-327.MantleGeochronology

Abstract: The 176Lu-176Hf radioactive decay system has been widely used to study planetary crust-mantle differentiation. Of considerable utility in this regard is zircon, a resistant mineral that can be precisely dated by the U-Pb chronometer and record its initial Hf isotope composition due to having low Lu/Hf. Here we review zircon U-Pb age and Hf isotopic data mainly obtained over the last two decades and discuss their contributions to our current understanding of crust-mantle evolution, with emphasis on the Lu-Hf isotope composition of the bulk silicate Earth (BSE), early differentiation of the silicate Earth, and the evolution of the continental crust over geologic history. Meteorite zircon encapsulates the most primitive Hf isotope composition of our solar system, which was used to identify chondritic meteorites best representative of the BSE (176Hf/177Hf = 0.282793 ± 0.000011; 176Lu/177Hf = 0.0338 ± 0.0001). Hadean-Eoarchean detrital zircons yield highly unradiogenic Hf isotope compositions relative to the BSE, providing evidence for the development of a geochemically enriched silicate reservoir as early as 4.5 Ga. By combining the Hf and O isotope systematics, we propose that the early enriched silicate reservoir has resided at depth within the Earth rather than near the surface and may represent a fractionated residuum of a magma ocean underlying the proto-crust, like urKREEP beneath the anorthositic crust on the Moon. Detrital zircons from world major rivers potentially provide the most robust Hf isotope record of the preserved granitoid crust on a continental scale, whereas mafic rocks with various emplacement ages offer an opportunity to trace the Hf isotope evolution of juvenile continental crust (from ?Hf[4.5 Ga] = 0 to ?Hf[present] = + 13). The river zircon data as compared to the juvenile crust composition highlight that the supercontinent cycle has controlled the evolution of the continental crust by regulating the rates of crustal generation and intra-crustal reworking processes and the preservation potential of granitoid crust. We use the data to explore the timing of generation of the preserved continental crust. Taking into account the crustal residence times of continental crust recycled back into the mantle, we further propose a model of net continental growth that stable continental crust was firstly established in the Paleo- and Mesoarchean and significantly grew in the Paleoproterozoic.
DS1920-0034
1920
Hibsch, J.E.Hibsch, J.E.Geologische Karte des " Bohmischen Mittelgebirges " Blats Xiv ( Meronitz-trebnitz) Nebst Erlauterungen.Verlag Der Gesellschaft Zur Forderung Deutscher Wissenschaft, 120P.GlobalGem, Diamonds, Kimberley
DS1930-0164
1934
Hibsch, J.E.Hibsch, J.E.Die Minerale des " Bohmischen Mittelgebirges "Wien: Jena Verlag Von Gustav-fischer., 196P.GlobalDiamonds, Kimberley
DS201904-0757
2019
HichamMalavergegne, V., Bureau, H., Raepsaet, C., Gaillard, C., Poncet, F., Surble, M., Sifre, S., Shcheka, D., Fourdrin, S., Deldicque, C., Khodja, D., HichamExperimental constraints on the fate of H and C during planetary core-mantle differentiation. Implications for the Earth.Icarus - New York, Vol. 321, 1, pp. 473-485.Mantlecarbon

Abstract: Hydrogen (H) and carbon (C) have probably been delivered to the Earth mainly during accretion processes at High Temperature (HT) and High Pressure (HP) and at variable redox conditions. We performed HP (1-15?GPa) and HT (1600-2300°C) experiments, combined with state-of-the-art analytical techniques to better understand the behavior of H and C during planetary differentiation processes. We show that increasing pressure makes H slightly siderophile and slightly decreases the highly siderophile nature of C. This implies that the capacity of a growing core to retain significant amounts of H or C is mainly controlled by the size of the planet: small planetary bodies may retain C in their cores while H may have rather been lost in space; larger bodies may store both H and C in their cores. During the Earth's differentiation, both C and H might be sequestrated in the core. However, the H content of the core would remain one or two orders of magnitude lower than that of C since the (H/C)core ratio might range between 0.04 and 0.27.
DS202007-1181
2020
Hichmuth, K.Stern, T., Lamb, S., Moore, J.D.P., Okaya, D., Hichmuth, K.High mantle seismic P-wave speeds as a signature for gravitational spreading of superplumes. Science Adavances, Vol. 6, eaba7118 May 27, 9p. PdfAsia, Javageophysics -seismic

Abstract: New passive- and active-source seismic experiments reveal unusually high mantle P-wave speeds that extend beneath the remnants of the world’s largest known large igneous province, making up the 120-million-year-old Ontong-Java-Manihiki-Hikurangi Plateau. Sub-Moho Pn phases of ~8.8 ± 0.2 km/s are resolved with negligible azimuthal seismic anisotropy, but with strong radial anisotropy (~10%), characteristic of aggregates of olivine with an AG crystallographic fabric. These seismic results are the first in situ evidence for this fabric in the upper mantle. We show that its presence can be explained by isotropic horizontal dilation and vertical flattening due to late-stage gravitational collapse and spreading in the top 10 to 20 km of a depleted, mushroom-shaped, superplume head on a horizontal length scale of 1000 km or more. This way, it provides a seismic tool to track plumes long after the thermal effects have ceased.
DS2002-0373
2002
Hickey, P.DeMull, T.J., Spenceley, J., Hickey, P.Batu Hijau: from discovery to productionMining Engineering, Vol.54.4,April,pp.13-24.Indonesia, SumbawaCopper, mining, Deposit - Batu Hijau
DS2002-0714
2002
Hickey Vargas, R.Hickey Vargas, R., Sun, M., Lopez Escoba, Moren RoaMultiple subduction components in mantle wedge: evidence eruptive centers Central South Volcanic ZoneGeology, Vol.30,3,March,pp.199-202.ChileSubduction, Metallogeny
DS1991-0711
1991
Hickey-Vargas, P.Hickey-Vargas, P.Peeled or mashed? Andean magma- South AmericaNature, Vol. 350, No. 6317, April 4, pp. 381-382South AmericaMagma Crust Mantle, Genesis
DS200612-1306
2005
HickinSimandl, G.J., Ferbey, T., Levson, V.M., Robinson, N.D., Lane, R., Smith, R., Demchuk, Raudsepp, HickinKimberlite and diamond indicator minerals in northeast British Columbia, Canada - a reconnaissance survey.British Columbia Geological Survey, Geofile 2005-25, 25p.Canada, British ColumbiaGeochemistry, geochronology, Buffalo Head Terrane
DS2002-0715
2002
Hickin, A.S.Hickin, A.S., Paulen, R.C.Delineation of a placer diamond and gold resource in Guyana: an application of GIS to exploration.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.49., p.49.Guyana, South AmericaGeophysics - GPR survey, Deposit - Potaro district
DS2002-0716
2002
Hickin, A.S.Hickin, A.S., Paulen, R.C.Delineation of a placer diamond and gold resource in Guyana: an application of GIS to exploration.Gac/mac Annual Meeting, Saskatoon, Abstract Volume, P.49., p.49.Guyana, South AmericaGeophysics - GPR survey, Deposit - Potaro district
DS1995-0791
1995
Hickin, E.J.Hickin, E.J.River geomorphologyJohn Wiley and Sons, $ 100.00GlobalBook -ad, Geomorphology -river
DS1995-0792
1995
Hickin, E.J.Hickin, E.J.River geomorphology.... Conference papers Britain, Spain, Italy, European and United States research.John Wiley and Sons, approx. 100.00GlobalBook -review GSA Today May 1996 p. 27., River geomorphology -not specific to diamonds
DS1984-0353
1984
Hickling, J.E.Hickling, J.E.A Comparison of Diamond Exploration Techniques Used in Australia.Darwin Conference, Conference Series Australasian Institute Min., No. 13, PP. 111-118.Australia, Western AustraliaProspecting, Sampling, Techniques
DS1994-0770
1994
Hickling CorpHickling CorpEnvironmental solutions for the mining and mineral processing industry indeveloping countriesHickling, GlobalBook -ad, Compendium of agencies
DS200712-1109
2007
Hickman, A.H.Van Kranendonk, M.J., Hugh Smithies, R., Hickman, A.H., Champion, D.C.Review: secular tectonic evolution of Archean continental crust: interplay between horizontal and vertical processes in the formation of the Pilbara Craton, Australia.Terra Nova, Vol. 19, 1, Feb. pp. 1-38.AustraliaTectonics
DS201503-0181
2015
Hickman, A.H.Van Kranendonk, M.J., Smithies, R.H., Griffin, W.L., Huston, D.L., Hickman, A.H., Champion, D.C., Anhaeusser, C.R., Pirajno, F.Making it thick: a volcanic plateau origin of Paleoarchean continental lithosphere of the Pilbara and Kaapvaal cratons.Geological Society of London Special Publication: Continent formation through time., No. 389, pp. 83-111.Australia, Africa, South AfricaGeotectonics
DS1995-0793
1995
Hickman, S.Hickman, S., Sibson, R., Bruhn, R.Introduction to special section: mechanical involvement of fluids infaultingJournal of Geophysical Research, Vol. 100, No.B7, July 10, pp. 12, 831-840GlobalStructure, Fluids -faulting
DS1994-0771
1994
Hickman, S.H.Hickman, S.H., et al.Proceedings of workshop LXIII United States Geological Survey (USGS) Red Book conference on mechanical involvement of fluids in faultingUnited States Geological Survey (USGS) Open File, No. 94-0228, $ 94.00 United StatesGlobalBook -table of contents, Faulting, structure
DS1989-0633
1989
Hickmott, D.D.Hickmott, D.D.Rare earth element zoning in pyrope rich garnets from mantle xenolithsCarnegie Institution, Annual Report of the Director of the Geophysical, No. 2150, July 1-1988 -June 30, 1989 pp. 6-10South AfricaMantle xenoliths, Craton -Kaapvaal
DS1990-0689
1990
Hickmott, D.D.Hickmott, D.D., Sorensen, S., Rogers, P.Trace element abundances in minerals from a metasomatized garnet-amphibolite Catalin a schist ,southern CaliforniaGeological Society of America (GSA) Annual Meeting, Abstracts, Vol. 22, No. 7, p. A349CaliforniaGeochemistry, Pixie trace elements
DS1940-0009
1940
Hickok, W.O.Hickok, W.O., Moyer, F.T.Geology and Mineral Resources of Fayette County, PennsylvaniPennsylvania Geological Survey Bulletin., No. C-26, SER. 4, 530P.United States, Appalachia, PennsylvaniaGeology
DS1987-0790
1987
Hicks, D.L.Whitten, T.E.H., Bornhorst, T.J., Gongshi Li, Hicks, D.L., BeckwithSuites, subdivision of batholiths and igneous rock classification:geological and mathematical conceptualizationAmerican Journal of Science, Vol. 287, April pp. 332-352GlobalClassification, Igneous rocks
DS201912-2784
2019
Hicks, N.Gilfillan, S.M.V., Gyore, D., Flude, S., Johnson, G., Bond, C.E., Hicks, N., Lister, R., Jones, D.G., Kremer, Y., Hazeldine, R.S., Stuart, F.M.Noble gases confirm plume related mantle degassing beneath southern Africa.Nature Communications, Vol. 10, 1, 10.1038/s41467-019-1244-6Africa, South Africaplumes

Abstract: Southern Africa is characterised by unusually elevated topography and abnormal heat flow. This can be explained by thermal perturbation of the mantle, but the origin of this is unclear. Geophysics has not detected a thermal anomaly in the upper mantle and there is no geochemical evidence of an asthenosphere mantle contribution to the Cenozoic volcanic record of the region. Here we show that natural CO2 seeps along the Ntlakwe-Bongwan fault within KwaZulu-Natal, South Africa, have C-He isotope systematics that support an origin from degassing mantle melts. Neon isotopes indicate that the melts originate from a deep mantle source that is similar to the mantle plume beneath Réunion, rather than the convecting upper mantle or sub-continental lithosphere. This confirms the existence of the Quathlamba mantle plume and importantly provides the first evidence in support of upwelling deep mantle beneath Southern Africa, helping to explain the regions elevation and abnormal heat flow.
DS2000-0409
2000
Hicks, N.O.Hicks, N.O., Keller, G.R., Simiyu, S.M.An integrated interpretation of structure of the upper crust of the Kenya Rift from remote sensing, gravity14th. International Conference Applied Remote Sensing, Nov. 1p. abstractKenyaRemote sensing, Tectonics
DS1975-0212
1975
Hicks, W.D.Wolfe, W.J., Lee, H.A., Hicks, W.D.Heavy Mineral Indicators in Alluvial and Esker Gravels of The Moose River Basin, James Bay Lowlands.Ontario Geological Survey Geology Report, No. 126, 60P.Canada, Ontario, James Bay LowlandsProspecting, Geochemistry, Sextant, Coral Rapids, Wacousta
DS1989-0634
1989
Hicock, S.R.Hicock, S.R., Dreimanis, A.Sunnybrook drift indicates a grounded early Wisconsin glacier in the Lake Ontario basinGeology, Vol. 17, No. 2, February pp. 169-172OntarioGeomorphology
DS1989-0635
1989
Hicock, S.R.Hicock, S.R., Kristjansson, F.J.Gold exploration using tills of the Beardmore-Geraldton area, northernOntarioThe Canadian Mining and Metallurgical Bulletin (CIM Bulletin), Vol. 82, No. 922, February pp. 50-54OntarioGeochemistry -Till, Gold -Beardmore Geraldton
DS1989-0636
1989
Hicock, S.R.Hicock, S.R., Kristjansson, F.J., Sharpe, D.R.Carbonate till as a soft bed for Pleistocene ice streams on the Canadian Shield north of Lake SuperiorCanadian Journal of Earth Sciences, Vol. 26, No. November pp. 2249-2254OntarioGeomorphology, Ice flow indicators
DS1992-0707
1992
Hicock, S.R.Hicock, S.R., Dreimanis, A.Deformation till in the Great Lakes region: implications for rapid flow along the south-central margin of the Laurentide Ice SheetCanadian Journal of Earth Sciences, Vol. 29, No. 7, July, pp. 1565-1579Ontario, Great LakesGeomorphology, Till, Laurentide Ice Sheet
DS200612-1032
2006
Hicock, S.R.Parsons, S.R.G., Hicock, S.R., Morris, T.F.Quaternary geology of the Ville Marie area, Quebec, and the location of potential diamond bearing kimberlite pipes.SEG 2006 Conference, Wealth Creation in the Minerals Industry, May 14-16, Keystone Colorado USA, Abtract Volume p. 346. ( 1p.)Canada, QuebecGeology - geomorphology, overburden
DS201201-0858
2011
Hicock, S.R.Ozyer, C.A., Hicock, S.R.Identifying kimberlite indicator mineral dispersal trains in the Pelly Bay region, Nunavut, Canada using GIS interpolation.Geochemistry, Exploration, Environment, Analysis, Vol. 11, 4, Nov. pp. 335-350.Canada, NunavutGeochemistry - KIM
DS200612-0599
2006
Hidaka, H.Horie, K., Komiya, T., Maruyama, S., Hirata, T., Hidaka, H., Windley, B.F.4.2 Ga zircon xenocryst in an Acasta gneiss from northwestern Canada: evidence for early continental crust.Geology, Vol.34, 4, April pp. 245-248.Canada, Northwest TerritoriesGeochronology, spectrometry
DS201312-0320
2013
Hidas, K.Gonzalez-Jimienez, J.M., Marchesi, C., Griffin, W.L., Gutierrez-Narbona, R., Lorand, J-P., O'Reilly, S.Y., Garrido, C.J., Gervilla, F., Pearson, N.J., Hidas, K.Transfer of Os isotopic signatures from peridotite to chromitite in the subcontinental mantle: insights from in situ analysis of platinum-group and base metal minerals (Ojen peridotite massif, southern Spain.Lithos, Vol. 164-167, pp. 74-85.Europe, SpainChromitite
DS201312-0574
2013
Hidas, K.Marchesi, C., Garrido, C.J., Bosch, D., Bodinier, J-L., Gervilla, F., Hidas, K.Mantle refertilization by melts of crustal derived garnet pyroxenite: evidence from the Ronda Peridotite massif, southern Spain.Earth and Planetary Interiors, Vol. 362, pp. 66-75.Europe, SpainRonda - pyroxenite. Melts
DS201412-0548
2014
Hidas, K.Marchesi, C., Dale, C.W., Garrdo, C.J., Pearson, D.G., Bosch, D., Bodinier, J-L., Gervilla, F., Hidas, K.Fractionation of highly siderophile elements in refertilized mantle: implications for the Os isotope composition of basalts.Earth and Planetary Science Letters, Vol. 400, pp. 33-44.MantleRonda peridotite
DS201704-0650
2016
Hidas, K.Varas-Reu, M.I., Garrido, C.J., Marchesi, C., Bodinier, J-L., Frets, E., Bosch, D., Tommasi, A., Hidas, K., Targuisti, K.Refertilization processes of the subcontinental lithospheric mantle: the record of the Beni Bousera orogenic peridotite ( Rif Belt, northern Morocco).Journal of Petrology, Vol. 57, 11-12, pp. 2251-2270.Africa, MoroccoDeposit - Beni Bousera

Abstract: Correlations between major and minor transition elements in tectonically emplaced orogenic peridotites have been ascribed to variable degrees of melt extraction and melt-rock reaction processes, leading to depletion or refertilization. To elucidate how such processes are recorded in the subcontinental lithospheric mantle, we processed a large geochemical dataset for peridotites from the four tectono-metamorphic domains of the Beni Bousera orogenic massif (Rif Belt, northern Morocco). Our study reveals that variations in bulk-rock major and minor elements, Mg-number and modal mineralogy of lherzolites, as well as their clinopyroxene trace element compositions, are inconsistent with simple partial melting and mainly resulted from different reactions between melts and depleted peridotites. Up to 30% melting at <3 GPa and cryptic metasomatism can account for the geochemical variations of most harzburgites. In Grt-Sp mylonites, melting and melt-rock reactions are masked by tectonic mixing with garnet pyroxenites and subsolidus re-equilibration. In the rest of the massif, lherzolites were mostly produced by refertilization of a refractory protolith (Mg-number = 91, Ol = 70%, Cpx/Opx = 0.4) via two distinct near-solidus, melt- rock reactions: (1) clinopyroxene and orthopyroxene precipitation and olivine consumption at melt/rock ratios <0.75 and variable mass ratio between crystallized minerals and infiltrated melt ®, which are recorded fairly homogeneously throughout the massif; (2) dissolution of orthopyroxene and precipitation of clinopyroxene and olivine at melt/rock ratios <1 and R = 0.2-0.3, which affected mainly the Arie` gite-Seiland and Seiland domains. The distribution of secondary lherzolites in the massif suggests that the first refertilization reaction occurred prior to the differentiation of the Beni Bousera mantle section into petro-structural zones, whereas the second reaction was associated with the development of the tectono-metamorphic domains. Our data support a secondary, refertilization-related origin for most lherzolites in orogenic peridotite massifs.
DS201806-1258
2018
Hidas, K.Varas-Reus, M.I., Garrido, C.J., Marchesi, C., Bosch, D., Hidas, K.Genesis of ultra-high pressure garnet pyroxenites in orogenic peridotites and its bearing on the compositional heterogeneity of the Earth's mantle. Ronda, Beni BouseraGeochimica et Cosmochimica Acta, Vol. 232, pp. 303-328.Africa, Morocco, Europe, SpainUHP

Abstract: We present an integrated geochemical study of ultra-high pressure (UHP) garnet pyroxenites from the Ronda and Beni Bousera peridotite massifs (Betic-Rif Belt, westernmost Mediterranean). Based on their Sr-Nd-Pb-Hf isotopic systematics, we classify UHP garnet pyroxenites into three groups: Group A pyroxenites (Al 2 O 3 : 15-17.5 wt. %) have low initial 87 Sr/ 86 Sr, relatively high ? Nd , ? Hf and 206 Pb/ 204 Pb ratios, and variable 207 Pb/ 204 Pb and 208 Pb/ 204 Pb. Group B pyroxenites (Al 2 O 3 < 14 wt. %) are characterized by high initial 87 Sr/ 86 Sr and relatively low ? Nd , ? Hf and 206 Pb/ 204 Pb ratios. Group C pyroxenites (Al 2 O 3 ~ 15 wt. %) have depleted radiogenic signatures with relatively low initial 87 Sr/ 86 Sr and 206 Pb/ 204 Pb, high ? Nd and ? Hf , and their 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios are similar to those of Group B pyroxenites. The major and trace element and isotopic compositions of UHP garnet pyroxenites support their derivation from ancient (1.5-3.5 Ga) oceanic crust recycled into the mantle and intimately stirred with peridotites by convection. However, the genesis of these pyroxenites requires also the involvement of recycled continental lower crust with an isotopic composition akin to the lower crustal section of the lithosphere where these UHP garnet pyroxenites now reside in. These oceanic and continental crustal components were stirred in different proportions in the convective mantle, originating pyroxenites with a more marked geochemical imprint of either oceanic (Group A) or continental lower crust (Group B), or hybrid compositions (Group C). The pyroxenite protoliths likely underwent several melting events, one of them related to the formation of the subcontinental lithospheric mantle and continental crust, generating restitic UHP garnet pyroxenites now preserved in the Ronda and Beni Bousera orogenic peridotites. The extent of melting was mostly 3 controlled by the bulk Mg-number (Mg#) of the pyroxenite protoliths, where protoliths with low Mg# experienced higher degrees of partial melting than sources with higher Mg#. Positive Eu and Sr anomalies in bulk rocks, indicative of their origin from cumulitic crustal gabbros, are preserved mostly in high Mg# pyroxenites due to their higher melting temperatures and consequent lower partial melting degrees. The results of this study show that the genesis of UHP garnet pyroxenites in orogenic peridotites requires a new recipe for the marble cake mantle hypothesis, combining significant recycling and stirring of both oceanic and continental lower crust in the Earth's mantle. Furthermore, this study establishes a firm connection between the isotopic signatures of UHP pyroxenite heterogeneities in the mantle and the continental lower crust.
DS201808-1794
2018
Hidas, K.Varas-Reu, M.I., Garrido, C.J., Marchesi, C., Bosch, D., Hidas, K.Genesis of ultra high pressure garnet pyroxenites in orogenic peridotites and its bearing on the compositional heterogeneity of the Earth's mantle.Geochimica et Cosmochimica Acta, Vol. 232, pp. 303-328.Mantledeposit - Ronda, Beni Bousera

Abstract: We present an integrated geochemical study of ultra-high pressure (UHP) garnet pyroxenites from the Ronda and Beni Bousera peridotite massifs (Betic-Rif Belt, westernmost Mediterranean). Based on their Sr-Nd-Pb-Hf isotopic systematics, we classify UHP garnet pyroxenites into three groups: Group A pyroxenites (Al2O3: 15-17.5?wt.%) have low initial 87Sr/86Sr, relatively high ?Nd, ?Hf and 206Pb/204Pb ratios, and variable 207Pb/204Pb and 208Pb/204Pb. Group B pyroxenites (Al2O3?
DS201904-0744
2019
Hidas, K.Hidas, K., Garrido, C.J., Booth-Rea, G., Marchesi, C., Bodinier, J-L., Dautria, J-M., Louni-Hacini, A., Azzouni-Sekkal, A.Lithosphere tearing along STEP faults and synkenetic formation of lherzolite and wehrlite in the shallow subcontinental mantle. OranSolid Earth, https://doi.org/10.5194 /se-2019-32 36p.Mantle, Africa, Algeriasubduction

Abstract: Subduction-Transform Edge Propagator (STEP) faults are the locus of continual lithospheric tearing at slab edges, resulting in sharp changes in the lithospheric and crustal thickness and triggering lateral and/or near-vertical mantle flow. However, the mechanisms at the lithospheric mantle scale are still poorly understood. Here, we present the microstructural study of olivine-rich lherzolite, harzburgite and wehrlite mantle xenoliths from the Oran volcanic field (Tell Atlas, NW Algeria). This alkali volcanic field occurs along a major STEP fault responsible for the Miocene westward slab retreat in the westernmost Mediterranean. Mantle xenoliths provide a unique opportunity to investigate the microstructures in the mantle section of a STEP fault system. The microstructures of mantle xenoliths show a variable grain size ranging from coarse granular to fine-grained equigranular textures uncorrelated with modal variations. The major element composition of the mantle peridotites provides temperature estimates in a wide range (790-1165?°C) but in general, the coarse-grained and fine-grained peridotites suggest deeper and shallower provenance depth, respectively. Olivine grain size in the fine-grained peridotites depends on the size and volume fraction of the pyroxene grains, which is consistent with pinning of olivine grain growth by pyroxenes as second phase particles. In the coarse-grained peridotites, well-developed olivine crystal preferred orientation (CPO) is characterized by orthorhombic and [100]-fiber symmetries, and orthopyroxene has a coherent CPO with that of olivine, suggesting their coeval deformation by dislocation creep at high-temperature. In the fine-grained microstructures, along with the weakening of the fabric strength, olivine CPO symmetry exhibits a shift towards [010]-fiber and the [010]- and [001]-axes of orthopyroxene are generally distributed subparallel to those of olivine. These data are consistent with deformation of olivine in the presence of low amounts of melts and the precipitation of orthopyroxenes from a melt phase. The bulk CPO of clinopyroxene mimics that of orthopyroxene via a topotaxial relationship of the two pyroxenes. This observation points to a melt-related origin of most clinopyroxenes in the Oran mantle xenoliths. The textural and geochemical record of the peridotites are consistent with interaction of a refractory harzburgite protolith with a high-Mg# melt at depth (resulting in the formation of coarse-grained clinopyroxene-rich lherzolite and wehrlite), and with a low-Mg# evolved melt in the shallow subcontinental lithospheric mantle (forming fine-grained harzburgite). We propose that pervasive melt-peridotite reaction - promoted by lateral and/or near-vertical mantle flow associated with lithospheric tearing - resulted in the synkinematic crystallization of secondary lherzolite and wehrlite and played a key effect on grain size reduction during the operation of the Rif-Tell STEP fault. Melt-rock reaction and secondary formation of lherzolite and wehrlite may be widespread in other STEP fault systems worldwide.
DS202102-0181
2020
Hidas, K.Dilissen, N., Hidas, K., Garrido, C.J., Kahl, W-A., Sanchez-Vizcaino, V.L.Graphical abstract: Morphological transition during prograde olivine growth formed by high-pressure dehydration of antigorite-serpentinite to chlorite-harzburgite in a subduction setting.Lithos, doi. 10.1016/j. lithos.2020.105949 1p. PdfMantlesubduction

Abstract: Crystal morphologies are essential for deciphering the reaction history of igneous and metamorphic rocks because they often record the interplay between nucleation and growth rates controlled by the departure from equilibrium. Here, we report an exceptional record of the morphological transition of olivine formed during subduction metamorphism and high-pressure dehydration of antigorite-serpentinite to prograde chlorite-harzburgite in the Almirez ultramafic massif (Nevado-Filábride Complex, Betic Cordillera, SE Spain). In this massif, rare varied-textured chlorite-harzburgite (olivine+enstantite+chlorite+oxides) —formed after high-P dehydration of antigorite-serpentinite— exhibits large olivine porphyroblasts made up of rounded cores mantled by coronas of tabular olivine grains, similar to single tabular olivines occurring in the matrix. The correlative X-ray ?-CT and EBSD study of two varied-textured chlorite-harzburgite samples show that tabular olivine in coronas is tabular on (100)Ol with c > b >> a, and grew in nearly the same crystallographic orientation as the rounded olivine cores of the porphyroblast. Quantitative textural analysis and mass balance indicate that varied-textured chlorite-harzburgite is the result of a two-stage nucleation and growth of olivine during the progress of the high-P dehydration of antigorite-serpentinite to chlorite-harzburgite reaction. The first stage occurred under a low affinity (?Gr) and affinity rate (?Gr/dt) of the antigorite dehydration reaction that resulted in a low time-integrated nucleation rate and isotropic growth of olivine, forming rounded olivine porphyroblasts. With further progress of the dehydration reaction, a second stage of relatively higher affinity and affinity rate resulted in a higher time-integrated nucleation rate of olivine coeval with a shift from isotropic to anisotropic olivine growth, leading to tabular olivines. The two-stage evolution resulted in olivine porphyroblasts made up of rounded cores mantled by coronas of tabular olivine grains characteristic of varied-texture chlorite-harzburgite. Although a switch to anisotropic tabular olivine in the second stage is consistent with the relative increase in the affinity and affinity rate, these changes cannot solely account for the growth of Almirez olivine tabular on (100). Tabular olivines in komatiites and other igneous rocks are tabular on (010)Ol with either a > c >> b, or a ? c > > b, in agreement with experimentally determined growth rates of olivine phenocrysts under moderate to high undercooling and cooling rates. On the other hand, olivine tabular on (100) is expected in the presence of highly polymerized fluids where inhibited growth of the olivine (100) and (010) interfaces occurs, respectively, due to dissociative and molecular adsorption of water monolayers. Rounded and tabular olivines in Almirez varied-textured chlorite-harzburgite show differing trace element compositions that we interpret as due to the infiltration of external fluids during antigorite dehydration. Isothermal infiltration of highly polymerized fluids would explain the shift in the affinity and affinity rate of the antigorite dehydration reaction, as well as the olivine morphology tabular on (100) due to the inhibited growth on the (100) and, to a lesser extent, (010). Our study shows that surface-active molecules may play an essential role in shaping the morphology of growing crystals during fluid-present metamorphic crystallization.
DS1860-0663
1890
Hidden, W.E.Hidden, W.E.Addendum to the Minerals and Mineral Localities of North Carolina.Elisha Mitchell Science Society Journal, Vol. 6, PT. 2, PP. 458.United States, North CarolinaDiamond Occurrence
DS1991-0712
1991
Hide, R.Hide, R., Dickey, J.O.Earth's variable rotationScience, Vol. 253, August 9, pp. 629-637GlobalEarth's rotation Geodesy, Core-mantle
DS1998-0618
1998
Hide, R.Hide, R.A note on topographic core mantle couplingPhys. Earth. Plan. International, Vol. 109, No. 1-2, Nov. pp. 91-92.MantleTomography
DS202011-2065
2020
Hidy, A.J.Vainer, S., Matmon, A., Erel, A.J., Hidy, A.J., Crouvi, O., De Wit, M., Geller, Y.Landscape responses to intraplate deformation in the Kalahari constrained by sediment provenance and chronology in the Okavango Basin.Basin Research, in press available Africa, South Africageomorphology

Abstract: The structural depression that occupies the Okavango Basin in southern Africa comprises a depo?centre within the intracratonic Kalahari Basin where sediments of the Cenozoic Kalahari Group have accumulated. The Okavango Basin has been formed due to stretching and subsidence at an area of diffused deformation, southwestwards to the main East African Rift System (EARS). Sediments from two full Kalahari Group sequences, located on opposite sides of the Gumare Fault that forms a major fault within the Okavango Basin, were studied to determine their provenance and chronology. Terrestrial Cosmogenic Nuclide (TCN) 26Al/10Be burial dating was used to constrain a chronostratigraphical framework, and Pb, Sr, and Nd isotopic ratios combined with geochemical and sedimentological analyses were applied to track the source areas of the sediments.Results indicate the following sequence of basin filling: (a) Accumulation between ca. 4-3 Ma during which the currently downthrown (southern) block received a mixture of sediments mostly from the Choma?Kalomo, Ghanzi?Chobe, and Damara terranes, and possibly from the Lufilian Belt and/or Karoo basalts during earlier stages of deposition. Simultaneously, the upthrown (northern) block received sediments from more distant Archean sources in the Zimbabwe and/or Kasai cratons, (b) Hiatus in sedimentation occurred at both sites between ca. 3-2 Ma, (c) Sediments on both sides of the Gumare Fault share a similar source (Angolan Shield) with minor distinct contributions to the downthrown block from the Kasai Craton and local sources input to the upthrown block, and (d) Regional distribution of aeolian sand since at least 1 Ma. The change in source areas is attributed to rearrangements of the drainage systems that were probably linked to vertical crustal movements on the margins of the Okavango Basin. The tectonically induced morphodynamics controlled the landscape evolution of the endorheic basin where vast lakes, wetlands and salt pans have developed through time.
DS200612-0381
2006
Hiemstra, J.F.Evans, D.J., Phillips, E.R., Hiemstra, J.F., Auton, C.A.Subglacial till: formation, sedimentary characteristics and classification.Earth Science Reviews, Vol. 78, 1-2, pp. 115-176.TechnologyClassification - not specific to diamonds
DS201212-0787
2012
Hier-Majander, S.Wimer, J., Hier-Majander, S.A three dimensional microgeodynamic model of melt geometry in the Earth's deep interior.Journal of Geophysical Research, Vol. 117, B4, B009012MantleCore, mantle boundary
DS201012-0277
2010
Hier-Majumder, S.Hier-Majumder, S., Revenaugh, J.Relationship between the viscosity and topography of the ultralow velocity zone near the core mantle boundary.Earth and Planetary Science Letters, Vol. 299, 3-4, pp. 382-386.MantleGeophysics - seismics
DS201706-1079
2017
Hier-Majumder, S.Hier-Majumder, S., Tauzin, B.Pervasive upper mantle melting beneath the western USA.Earth and Planetary Science Letters, Vol. 463, pp. 25-35.United Statesmelting

Abstract: We report from converted seismic waves, a pervasive seismically anomalous layer above the transition zone beneath the western US. The layer, characterized by an average shear wave speed reduction of 1.6%, spans over an area of ?1.8×106 km2?1.8×106 km2 with thicknesses varying between 25 and 70 km. The location of the layer correlates with the present location of a segment of the Farallon plate. This spatial correlation and the sharp seismic signal atop of the layer indicate that the layer is caused by compositional heterogeneity. Analysis of the seismic signature reveals that the compositional heterogeneity can be ascribed to a small volume of partial melt (0.5 ± 0.2 vol% on average). This article presents the first high resolution map of the melt present within the layer. Despite spatial variations in temperature, the calculated melt volume fraction correlates strongly with the amplitude of P-S conversion throughout the region. Comparing the values of temperature calculated from the seismic signal with available petrological constraints, we infer that melting in the layer is caused by release of volatiles from the subducted Farallon slab. This partially molten zone beneath the western US can sequester at least 1.2×1017 kg1.2×1017 kg of volatiles, and can act as a large regional reservoir of volatile species such as H or C.
DS200412-0825
2004
Hieronymous, C.Hieronymous, C., Baker, J.Deep subduction of the mantle wedge and the origin of OIB.Geochimica et Cosmochimica Acta, 13th Goldschmidt Conference held Copenhagen Denmark, Vol. 68, 11 Supp. July, ABSTRACT p.A560.MantleSubduction
DS200612-0738
2005
Hieronymus, B.Kotschoubey, B., Hieronymus, B., De Albuquerque, C.A.R.Disrupted peridotites and basalts from the Neoproterozoic Araguaia belt, (northern Brazil): remnants of a poorly evolved oceanic crust?Journal of South American Earth Sciences, Vol. 20, 3, Dec. pp. 211-230.South America, BrazilMetamorphism - Tocantins Group
DS1999-0306
1999
Hieronymus, C.F.Hieronymus, C.F., Bercovici, D.Alternating hotspot islands formed by the interaction of magma transportand lithosphere flexure.Nature, Vol. 397, No. 6720, Feb. 18, pp. 604-6.GlobalMagma, Hotspots
DS2001-0477
2001
Hieronymus, C.F.Hieronymus, C.F., Bercovici, D.A theoretical model of hot spot volcanism: control of volcanic spacing and patterns via magma dynamics...Journal of Geophysical Research, Vol. 106, No. 1, Jan. 10, pp. 683-702.MantleLithosphere stresses, Hotspots
DS201012-0278
2010
Hieronymus, C.F.Hieronymus, C.F., Goes, S.Complex cratonic seismic structure from thermal models of the lithosphere: effects of variations in deep radiogenic heating.Geophysical Journal International, Vol. 180, no. 3, pp. 999-1022.MantleGeophysics - seismics
DS202103-0386
2021
HietalaHall, A.M., Putkinen, N., Hietala,, S., Lindsberg, E., Holma, M.Ultra-slow cratonic denudation in Finland since 1.5 Ga indicated by tiered unconformities and impact structures.Precambrian Research, Vol. 352, 106000, 18p. PdfEurope, Finlandgeothermometry

Abstract: The Earth’s cratons are traditionally regarded as tectonically stable cores that were episodically buried by thin sedimentary covers. Cratonic crust in southern Finland holds seven post-1.7 Ga tiered unconformities, with remnants of former sedimentary covers. We use the geometries of the tiered unconformities, along with previously dated impact structures and kimberlite and carbonatite pipes, to reconstruct the erosion and burial history of the craton and to derive estimates of depths of erosion in basement and former sedimentary rocks. The close vertical spacing (<200 m) of the unconformities and the survival of small (D ? 5 km) Neoproterozoic and Early Palaeozoic impact structures indicate minor later erosion. Average erosion rates (<2.5 m/Ma) in basement and cover are amongst the lowest reported on Earth. Ultra-slow erosion has allowed the persistence in basement fractures of Phanerozoic fracture coatings and Palaeogene groundwater and microbiomes. Maximum thicknesses of foreland basin sediments in Finland during the Sveconorwegian and Caledonide orogenies are estimated as ~1.0 km and <0.68-1.0 km, respectively. Estimated losses of sedimentary cover derived from apatite fission track thermochronology are higher by factors of at least 2 to 4. A dynamic epeirogenic history of the craton in Finland, with kilometre-scale burial and exhumation, proposed in recent thermochronological models is not supported by other geological proxies. Ultra-slow erosion rates in southern Finland reflect long term tectonic stability and burial of the craton surface for a total of ~1.0 Ga beneath generally thin sedimentary cover.
DS1950-0179
1954
Higazy, R.A.Higazy, R.A.Trace Elements of Volcanic Ultrabasic Potassic Rocks of South Western UgAnd a and Adjoining Parts of the Belgian Congo.Geological Society of America (GSA) Bulletin., Vol. 65, PP. 39-70.Democratic Republic of Congo, Uganda, Central AfricaRelated Rocks Engineering
DS202003-0367
2020
Higelius, G.Turetsky, M.R., Abbott, B.W., Jones, M.C., Walter Anthony, K.. Olefeldt, D., Schuur, E.A.G., Grosse, G., Kuhry, P., Higelius, G., Koven, C., Lawrence, D.M., Gibson, C., Sannel, A.B.K., McGuire, A.D.Carbon release through abrupt permafrost thaw. ( not specific to diamonds but interest)Nature Geoscience, Vol. 13, pp. 138-143.Mantlecarbon

Abstract: The permafrost zone is expected to be a substantial carbon source to the atmosphere, yet large-scale models currently only simulate gradual changes in seasonally thawed soil. Abrupt thaw will probably occur in <20% of the permafrost zone but could affect half of permafrost carbon through collapsing ground, rapid erosion and landslides. Here, we synthesize the best available information and develop inventory models to simulate abrupt thaw impacts on permafrost carbon balance. Emissions across 2.5?million?km2 of abrupt thaw could provide a similar climate feedback as gradual thaw emissions from the entire 18?million?km2 permafrost region under the warming projection of Representative Concentration Pathway 8.5. While models forecast that gradual thaw may lead to net ecosystem carbon uptake under projections of Representative Concentration Pathway 4.5, abrupt thaw emissions are likely to offset this potential carbon sink. Active hillslope erosional features will occupy 3% of abrupt thaw terrain by 2300 but emit one-third of abrupt thaw carbon losses. Thaw lakes and wetlands are methane hot spots but their carbon release is partially offset by slowly regrowing vegetation. After considering abrupt thaw stabilization, lake drainage and soil carbon uptake by vegetation regrowth, we conclude that models considering only gradual permafrost thaw are substantially underestimating carbon emissions from thawing permafrost.
DS201212-0299
2012
Higgie, K.Higgie, K., Tommasi, A.Deformation in a shallow partially molten mantle: constraints from natural systems.emc2012 @ uni-frankfurt.de, 1p. AbstractMantleMelting
DS1997-0504
1997
Higgin, J.Higgin, J., Harris, A.VAST: a program to locate and analyze volcanic thermal anomalies automatically from remotely sensed dataComputers and Geosciences, Vol. 23, No. 6, pp. 627-46GlobalVolcanics, Computers - VAST.
DS1992-0571
1992
Higgins, A.K.Gilotti, J.A., Friderichsen, J.D., Higgins, A.K., Steenfelt, A.A new eclogite province in the Arctic Caledonides, southeast Greenland 77to 78 degGeological Society of America (GSA) Abstract Volume, Vol. 24, No. 3, March p. 23. abstractGreenlandEclogite, Xenoliths
DS1985-0285
1985
Higgins, H.Higgins, H., Allen, J.M.A New Locality for Primary Xenolith Bearing Nephelinites In northwestern british ColumbiaCanadian Journal of Earth Sciences, Vol. 22, No. 10, pp. 1556-1559British ColumbiaBlank
DS202109-1472
2021
Higgins, J.A.Hoffman, P.F., Halverson, G.P., Schrag, D.P., Higgins, J.A., Domack, E.W., Macdonald, F.A., Pruss, S.B., Blattler, C.L., Crockford, P.W., Hodgin, E.B., Bellefroid, E.J., Johnson, B.W., Hodgskiss, M.S.W., Lamothe, K.G., LoBianco, S.J.C., Busch, J.F., HowesSnowballs in Africa: sectioning a long-lived Neoproterozoic carbonate platform and its bathyal foreslope ( NW Namibia). (Octavi Group)Earth Science Reviews , Vol. 219, 103616 231p. PdfAfrica, NamibiaCraton - Congo

Abstract: Otavi Group is a 1.5-3.5-km-thick epicontinental marine carbonate succession of Neoproterozoic age, exposed in an 800-km-long Ediacaran?Cambrian fold belt that rims the SW cape of Congo craton in northern Namibia. Along its southern margin, a contiguous distally tapered foreslope carbonate wedge of the same age is called Swakop Group. Swakop Group also occurs on the western cratonic margin, where a crustal-scale thrust cuts out the facies transition to the platformal Otavi Group. Subsidence accommodating Otavi Group resulted from S?N crustal stretching (770-655?Ma), followed by post-rift thermal subsidence (655-600?Ma). Rifting under southern Swakop Group continued until 650-635?Ma, culminating with breakup and a S-facing continental margin. No hint of a western margin is evident in Otavi Group, suggesting a transform margin to the west, kinematically consistent with S?N plate divergence. Rift-related peralkaline igneous activity in southern Swakop Group occurred around 760 and 746?Ma, with several rift-related igneous centres undated. By comparison, western Swakop Group is impoverished in rift-related igneous rocks. Despite low paleoelevation and paleolatitude, Otavi and Swakop groups are everywhere imprinted by early and late Cryogenian glaciations, enabling unequivocal stratigraphic division into five epochs (period divisions): (1) non-glacial late Tonian, 770-717?Ma; (2) glacial early Cryogenian/Sturtian, 717-661?Ma; (3) non-glacial middle Cryogenian, 661-646?±?5?Ma; (4) glacial late Cryogenian/Marinoan, 646?±?5-635?Ma; and (5) non-glacial early Ediacaran, 635-600?±?5?Ma. Odd numbered epochs lack evident glacioeustatic fluctuation; even numbered ones were the Sturtian and Marinoan snowball Earths. This study aimed to deconstruct the carbonate succession for insights on the nature of Cryogenian glaciations. It focuses on the well-exposed southwestern apex of the arcuate fold belt, incorporating 585?measured sections (totaling >190?km of strata) and?>?8764 pairs of ?13C/?18Ocarb analyses (tabulated in Supplementary On-line Information). Each glaciation began and ended abruptly, and each was followed by anomalously thick ‘catch-up’ depositional sequences that filled accommodation space created by synglacial tectonic subsidence accompanied by very low average rates of sediment accumulation. Net subsidence was 38% larger on average for the younger glaciation, despite its 3.5-9.3-times shorter duration. Average accumulation rates were subequal, 4.0 vs 3.3-8.8?m Myr?1, despite syn-rift tectonics and topography during Sturtian glaciation, versus passive-margin subsidence during Marinoan. Sturtian deposits everywhere overlie an erosional disconformity or unconformity, with depocenters ?1.6?km thick localized in subglacial rift basins, glacially carved bedrock troughs and moraine-like buildups. Sturtian deposits are dominated by massive diamictite, and the associated fine-grained laminated sediments appear to be local subglacial meltwater deposits, including a deep subglacial rift basin. No marine ice-grounding line is required in the 110 Sturtian measured sections in our survey. In contrast, the newly-opened southern foreslope was occupied by a Marinoan marine ice grounding zone, which became the dominant repository for glacial debris eroded from the upper foreslope and broad shallow troughs on the Otavi Group platform, which was glaciated but left nearly devoid of glacial deposits. On the distal foreslope, a distinct glacioeustatic falling-stand carbonate wedge is truncated upslope by a glacial disconformity that underlies the main lowstand grounding-zone wedge, which includes a proximal 0.60-km-high grounding-line moraine. Marinoan deposits are recessional overall, since all but the most distal overlie a glacial disconformity. The Marinoan glacial record is that of an early ice maximum and subsequent slow recession and aggradation, due to tectonic subsidence. Terminal deglaciation is recorded by a ferruginous drape of stratified diamictite, choked with ice-rafted debris, abruptly followed by a syndeglacial-postglacial cap-carbonate depositional sequence. Unlike its Sturtian counterpart, the post-Marinoan sequence has a well-developed basal transgressive (i.e., deepening-upward) cap dolomite (16.9?m regional average thickness, n?=?140) with idiosyncratic sedimentary features including sheet-crack marine cements, tubestone stromatolites and giant wave ripples. The overlying deeper-water calci-rhythmite includes crystal-fans of former aragonite benthic cement ?90?m thick, localized in areas of steep sea-floor topography. Marinoan sequence stratigraphy is laid out over ?0.6?km of paleobathymetric relief. Late Tonian shallow-neritic ?13Ccarb records were obtained from the 0.4-km-thick Devede Fm (~770-760?Ma) in Otavi Group and the 0.7-km-thick Ugab Subgroup (~737-717?Ma) in Swakop Group. Devede Fm is isotopically heavy, +4-8‰ VPDB, and could be correlative with Backlundtoppen Fm (NE Svalbard). Ugab Subgroup post-dates 746?Ma volcanics and shows two negative excursions bridged by heavy ?13C values. The negative excursions could be correlative with Russøya and Garvellach CIEs (carbon isotope excursions) in NE Laurentia. Middle Cryogenian neritic ?13C records from Otavi Group inner platform feature two heavy plateaus bracketed by three negative excursions, correlated with Twitya (NW Canada), Taishir (Mongolia) and Trezona (South Australia) CIEs. The same pattern is observed in carbonate turbidites in distal Swakop Group, with the sub-Marinoan falling-stand wedge hosting the Trezona CIE recovery. Proximal Swakop Group strata equivalent to Taishir CIE and its subsequent heavy plateau are shifted bidirectionally to uniform values of +3.0-3.5‰. Early Ediacaran neritic ?13C records from Otavi Group inner platform display a deep negative excursion associated with the post-Marinoan depositional sequence and heavy values (??+?11‰) with extreme point-to-point variability (?10‰) in the youngest Otavi Group formation. Distal Swakop Group mimics older parts of the early Ediacaran inner platform ?13C records, but after the post-Marinoan negative excursion, proximal Swakop Group values are shifted bidirectionally to +0.9?±?1.5‰. Destruction of positive and negative CIEs in proximal Swakop Group is tentatively attributed to early seawater-buffered diagenesis (dolomitization), driven by geothermal porewater convection that sucks seawater into the proximal foreslope of the platform. This hypothesis provocatively implies that CIEs originating in epi-platform waters and shed far downslope as turbidites are decoupled from open-ocean DIC (dissolved inorganic carbon), which is recorded by the altered proximal Swakop Group values closer to DIC of modern seawater. Carbonate sedimentation ended when the cratonic margins collided with and were overridden by the Atlantic coast-normal Northern Damara and coast-parallel Kaoko orogens at 0.60-0.58?Ga. A forebulge disconformity separates Otavi/Swakop Group from overlying foredeep clastics. In the cratonic cusp, where the orogens meet at a right angle, the forebulge disconformity has an astounding ?1.85?km of megakarstic relief, and km-thick mass slides were displaced gravitationally toward both trenches, prior to orogenic shortening responsible for the craton-rimming fold belt.
DS1993-0666
1993
Higgins, M.Higgins, M.Magma chambers and processes in anorthosite formationGeoscience Canada, Vol. 19, No. 4, December p. 172GlobalAnorthosite, Overview of conference
DS201906-1301
2019
Higgins, M.Higgins, M., Bedard, L.P., dos Santos, E., Vander Auwera, J.Lamprophyres, carbonatites and phoscorites of the Saguenay City alkali province, Quebec, CanadaGAC/MAC annual Meeting, 1p. Abstract p. 108.Canada, QuebecCcrbonatite

Abstract: The Saguenay City alkali province (~ 580 Ma) comprises the Saint-Honoré alkaline complex (carbonatite-syenite), lesser-known minor subsurface carbonatite intrusions and several sets of lamprophyre (sl) dykes. Flat-lying, north-dipping dykes (l-100 cm) that crop out close the Saguenay River/Fjord were formed by multiple intrusions of a very fluid magma. The dykes are continuously variable in composition from carbonatite to ultramafic lamprophyre. Olivine phenocrysts (l-3 mm) are pseudomorphed by serpentine but phlogopite phenocrysts (l-5 mm) are well preserved in a matrix of a fine-grained serpentine, chlorite and carbonate. A few dykes are phoscorites, with abundant phenocrysts of phlogopite, oxides, apatite and accessory baddeleyite. In all dykes, the matrix may have been originally fine-grained or even glassy, and subsequently altered by water dissolved in the original magma. Several dykes contain abundant xenoliths: mostly crustal and possibly one of mantle origin. Low-carbonate dykes have a narrow range in Sr isotopes (0.7030-0.7033) versus the wider range of high-carbonate dykes (0.7032-0.7046), but this distinction is not seen in ?Nd (3.4-4.9). Overall, it appears that each batch of magma was small and came from independent mantle sources. Recently, we found a new set of vertical, NW-directed lamprophyres around the Baie des Ha! Ha!, about 15 km south of the main swarm. They have phlogopite phenocrysts to 50 mm and olivine pseudomorphs. Their contrasting orientation suggests that they have a different age to the Saguenay River dykes, but they have yet to be dated. The overall pattern is of an extensive mantle source that delivered small volumes of volatile-rich ultramafic magmas over a long period. We consider that some of these magma batches accumulated and differentiated in a magma chamber beneath the Saint-Honoré alkaline complex, whereas others rose uninterrupted to high levels of the crust where they were emplaced as dykes.
DS201906-1322
2019
Higgins, M.McCausland, P., Higgins, M., LeCheminant, A., Jourdan, F., Hamilton, M., Murphy, J.B.Laurentia during the mid-Edicacaran: paleomagnetism and 580 Ma age of the Saint Honore alkali intrusion and related dykes, Quebec. GAC/MAC annual Meeting, 1p. Abstract p. 141.Canada, Quebecdeposit - Saint Honore

Abstract: We sampled the mid-Ediacaran Saint-Honoré alkali intrusion and related dykes in the Saguenay City region of Québec for paleomagnetic and U-Pb, 40Ar/39Ar geochonologic study. 40Ar/39Ar geochronology of phlogopite separates from carbonatite of the central intrusion return plateau ages with a weighted mean of 578.3 ± 3.5 Ma. Baddeleyite from a phoscorite dyke provides a concordant age of 580.25 ± 0.87 Ma for the crystallization of the dykes associated with the St-Honoré intrusive complex. Paleomagnetic results from the intrusion itself and related carbonatite and lamprophyre dykes exhibit some streaking between higher to moderate inclination directions, even at the site level, after screening to remove a steep, present-day viscous remanence. The predominant St-Honoré mean direction (13 sites), which is primary (baked contact test on the host Lac St-Jean anorthosite), is D = 119, I = 72.3°; ?95 = 9.5°, retained at higher coercivity and to high unblocking temperatures by titanomagnetite. Assuming a geocentric axial dipole, this result places the St. Honoré locality at 57° S at ~ 580 Ma, implying that Laurentia straddled mid-paleolatitudes at that time. Notably, the paleopole location at 27.2° N, 320.7 E (dp = 15°, dm = 17°) is consistent with similar mid-Ediacaran age paleopoles which place Laurentia at mid- to high paleolatitudes. The Saint-Honoré result implies that Laurentia had moved from low latitude in the early Ediacaran to higher southern paleolatitudes by 580-570 Ma, and then back to low paleolatitudes by as early as 564 Ma. Viewed as apparent polar wander (APW), this motion traces an 'Ediacaran loop' that can also be seen in similar-aged paleomagnetic results from at least two other paleocontinents. The similar APW loops suggest a role for true polar wander in Ediacaran geodynamics, and perhaps help to define a longitudinally-constrained global Ediacaran paleogeography.
DS1982-0274
1982
Higgins, M.D.Higgins, M.D., Allen, J.M.Carbonate Rich Basalt, Andesite and Dacite Associated with Nephelinites from Northwest British Columbia.Geological Society of America (GSA), Vol. 14, No. 7, P. 514. (abstract.).Canada, British ColumbiaBlank
DS1983-0303
1983
Higgins, M.D.Higgins, M.D., Shaw, D.M.Boron Abundance and Distribution in the Mantle, and the Bulk Boron Content of the Earth.Geological Association of Canada (GAC)/Mineralogical Association of Canada (MAC)/CGU, Vol. 8, ABSTRACT VOLUME P. A29. (abstract.)GlobalKimberlite, Lherzolite
DS1984-0354
1984
Higgins, M.D.Higgins, M.D.The Abundance of Boron in South African KimberlitesGeological Society of America (GSA), Vol. 16, No. 6, P. 539. (abstract.).South AfricaBlank
DS1985-0286
1985
Higgins, M.D.Higgins, M.D., Allen, J.M.A New Locality for Primary Xenolith Bearing Nephelinites In northwestern British Columbia.Canadian Journal of Earth Sciences., Vol. 22, No. 10, OCTOBER PP. 1556-1559.Canada, British ColumbiaNephelinite
DS1989-0637
1989
Higgins, M.D.Higgins, M.D.The two phases of Iapetus rifting in North AmericaGeological Association of Canada (GAC) Annual Meeting Program Abstracts, Vol. 14, p. A126. (abstract.)GlobalTectonics, Kapuskasing Zone
DS1989-0638
1989
Higgins, M.D.Higgins, M.D., Feininger, T., Martignole, J., Nantel, S.The Sept Iles layered mafic intrusion and the anorthosite complex of Riviere PentecoteGeological Association of Canada (GAC) Field Trip, May 17-21, NoQuebecXenoliths
DS1992-0363
1992
Higgins, M.D.Dickin, A.P., Higgins, M.D.Sm/neodymium evidence for a major 1.5 Ga crust forming event in the central Grenville ProvinceGeology, Vol. 20, No. 2, February pp. 137-140OntarioTectonics, Geochronology
DS1992-0708
1992
Higgins, M.D.Higgins, M.D., Van Breemen, O.The age of Lac Saint Jean anorthosite intrusion and associated mafic rocksCanadian Journal of Earth Sciences, Vol. 29, pp. 1412-23.QuebecGeochronology
DS1996-0628
1996
Higgins, M.D.Higgins, M.D., Van Breemen, O.Three generations of AMCG magmatism contact metamorphism and tectonism in Saguenay Lac Saint JeanPrecambrian Research, Vol. 79, pp. 327-46.QuebecGeochronology
DS200712-0435
2007
Higgins, S.Higgins, S.Canadian diamonds cut it.International Mining, July pp. 8-18.CanadaExploration companies - review
DS200712-0436
2007
Higgins, S.Higgins, S.Canadian diamonds cut it.International Mining, July pp. 8-18.CanadaExploration companies - review
DS200812-0153
2007
Higgs, B.Burek, C.V., Higgs, B.The role of women in the history of geology.New books, Tables of contents and costsGlobalGeneral interest?
DS2003-0619
2003
Higgs, G.Inzana, J., Kusky, T., Higgs, G., Tucker, R.Supervised classification of Land sat TM band ratio images and Land sat TM band ratioJournal of African Earth Sciences, Vol. 37, 1-2, July-August pp. 59-72.MadagascarRemote sensing - not specific to diamonds
DS200412-0870
2003
Higgs, G.Inzana, J., Kusky, T., Higgs, G., Tucker, R.Supervised classification of Land sat TM band ratio images and Land sat TM band ratio image with radar for geological interpretatiJournal of African Earth Sciences, Vol. 37, 1-2, July-August pp. 59-72.Africa, MadagascarRemote sensing - not specific to diamonds
DS201012-0279
2010
High Pressure Physics GroupHigh Pressure Physics Group, Lawrence Livermore National LaboratoryOhmic heating - laser heating - brief backgrounder - heating experiments at high pressure valuable in understanding behavior of materials.adg.gov, 2p.TechnologyOverview - brief using diamond anvil cells
DS2000-0790
2000
High River GoldQueenstake Res., High River GoldCommences legal proceeding against Incanore. Assets in Burkin a Faso include a mention of diamond properties.High River Gold, Aug. 30, 2p.GlobalNews item - press release, Incanore Gold Mines Ltd.
DS1989-0639
1989
High Tech Materials AlertHigh Tech Materials AlertVery high quality diamonds from a 'dirty' processHigh Tech Materials Alert, Vol. 6, No. 9, September pp. 1-4, 7GlobalCVD., Diamond synthesis
DS1990-0690
1990
High Tech Materials AlertHigh Tech Materials AlertDiamond semiconductor limitsHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 1, January p. 3GlobalNews item, Diamond synthesis
DS1990-0691
1990
High Tech Materials AlertHigh Tech Materials AlertEver closer to perfect diamond filmsHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 10, October p. 2GlobalNews item, Diamond synthesis
DS1990-0692
1990
High Tech Materials AlertHigh Tech Materials AlertMajor diamond breakthroughs- Norton achieves 1 mm diamond coatingsHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 11, November p. 1GlobalNews item, Diamond synthesis
DS1990-0693
1990
High Tech Materials AlertHigh Tech Materials AlertDiamond films, faster and cheaperHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 12, December p. 1GlobalNews item, Diamond synthesis
DS1990-0694
1990
High Tech Materials AlertHigh Tech Materials AlertSuperplastically formed ZnS/diamond compositesHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 3, March p. 2, 3GlobalNews item, Diamond synthesis
DS1990-0695
1990
High Tech Materials AlertHigh Tech Materials AlertDiamond theory- concentration of energy vacanciesHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 4, April p. 7GlobalNews item, Diamond synthesis
DS1990-0696
1990
High Tech Materials AlertHigh Tech Materials AlertNew diamond deposition processHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 7, July p. 8GlobalNews item, Diamond synthesis
DS1990-0697
1990
High Tech Materials AlertHigh Tech Materials AlertGE achieves new diamond properties.. more thermally conductive and more laser resistantHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 8, August p. 3GlobalNews item, Diamond synthesis
DS1990-0698
1990
High Tech Materials AlertHigh Tech Materials AlertLarger diamonds from Sumitomo 5 to 9 caratsHigh Tech Materials Alert, please note CVD not normally covered in refs., Vol. 7, No. 9, September p. 8GlobalNews item, Diamond synthesis
DS1985-0499
1985
Highley, D.E.Notholt, A.J.G., Highley, D.E., Harding, R.R.Investigation of Phosphate (apatite) Potential of Loch Borralan Igneous Complex, Northwest Highlands of Scotland.Institute of Mining and Metallurgy. Transactions, Vol. 94, SECT.B, PP. B 58-B65.ScotlandCarbonatite
DS1990-1121
1990
Highley, D.E.Notholt, A.J.G., Highley, D.E., Deans, T.Economic minerals in carbonatites and associated alkaline rocksTransactions of the Institute of Mining and Metallurgy (IMM), Vol. 99, Section B, May-August pp. B59-B80GlobalCarbonatite, Good review-economics
DS201910-2269
2018
Hignett, S.Kavanagh, J.L., Burns, A.J., Hilmi Hazim, S., Wood, E.P., Martin, S.A., Hignett, S., Dennis, D.J.C.Challenging dyke ascent models using novel laboratory experiments: implications for reinterpreting evidence of magma accent and volcanism.Journal of Volcanology and Geothermal Research, Vol. 354, pp. 87-101.Mantlemagmatism

Abstract: Volcanic eruptions are fed by plumbing systems that transport magma from its source to the surface, mostly fed by dykes. Here we present laboratory experiments that model dyke ascent to eruption using a tank filled with a crust analogue (gelatine, which is transparent and elastic) that is injected from below by a magma analogue (dyed water). This novel experimental setup allows, for the first time, the simultaneous measurement of fluid flow, sub-surface and surface deformation during dyke ascent. During injection, a penny-shaped fluid-filled crack is formed, intrudes, and traverses the gelatine slab vertically to then erupt at the surface. Polarised light shows the internal stress evolution as the dyke ascends, and an overhead laser scanner measures the surface elevation change in the lead-up to dyke eruption. Fluorescent passive-tracer particles that are illuminated by a laser sheet are monitored, and the intruding fluid's flow dynamics and gelatine's sub-surface strain evolution is measured using particle image velocimetry and digital image correlation, respectively. We identify 4 previously undescribed stages of dyke ascent. Stage 1, early dyke growth: the initial dyke grows from the source, and two fluid jets circulate as the penny-shaped crack is formed. Stage 2, pseudo-steady dyke growth: characterised by the development of a rapidly uprising, central, single pseudo-steady fluid jet, as the dyke grows equally in length and width, and the fluid down-wells at the dyke margin. Sub-surface host strain is localised at the head region and the tail of the dyke is largely static. Stage 3, pre-eruption unsteady dyke growth: an instability in the fluid flow appears as the central fluid jet meanders, the dyke tip accelerates towards the surface and the tail thins. Surface deformation is only detected in the immediate lead-up to eruption and is characterised by an overall topographic increase, with axis-symmetric topographic highs developed above the dyke tip. Stage 4 is the onset of eruption, when fluid flow is projected outwards and focused towards the erupting fissure as the dyke closes. A simultaneous and abrupt decrease in sub-surface strain occurs as the fluid pressure is released. Our results provide a comprehensive physical framework upon which to interpret evidence of dyke ascent in nature, and suggest dyke ascent models need to be re-evaluated to account for coupled intrusive and extrusive processes and improve the recognition of monitoring signals that lead to volcanic eruptions in nature.
DS201012-0312
2010
HigoIrifune, T., Nishiyama, Tange, Kono, Shinmel, Kinoshita, Negishi, Kato, Higo, FunakoshiPhase transitions, densities and sound velocities of mantle and slab materials down to the upper part of the lower mantle.International Mineralogical Association meeting August Budapest, abstract p. 142.MantleSubduction
DS200612-0625
2006
Higo, Y.Irifune, T., Higo, Y., Inoue, T., Funakoshi, K.Ultrasonic velocities of majorite garnet and mineralogy of the mantle transition region.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 108.MantleMTR - interferometry
DS200812-0503
2008
Higo, Y.Irifune, T., Higo, Y., Inoue, T., Kono, Y., Ohfuji, H., Funakoshi, K.Sound velocities of majorite garnet and the composition of the mantle transition zone.Nature, Vol. 451, 7180, pp. 814-817.MantleGeophysics - seismics
DS201412-0355
2014
Higo, Y.Higo, Y., Matsui, M., Irifune, T.Development of ultrasonic measurement technique under lower mantle conditions.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 1p. AbstractTechnologyPerovskite
DS201811-2597
2018
Higo, Y.Ohuchi, T., Lei, X., Higo, Y., Tange, Y., Sakai, T., Fujino, K.Semi-brittle behavior of wet olivine aggregates: the role of aqueous fluid in faulting at upper mantle pressures.Contributions to Mineralogy and Petrology, Vol. 173, 21p. Doi.org/10.1007/s00410-018-1515-9Mantlesubduction

Abstract: The role of aqueous fluid in fracturing in subducting slabs was investigated through a series of deformation experiments on dunite that was undersaturated (i.e., fluid-free) or saturated with water (i.e., aqueous-fluid bearing) at pressures of 1.0-1.8 GPa and temperatures of 670-1250 K, corresponding to the conditions of the shallower regions of the double seismic zone in slabs. In situ X-ray diffraction, radiography, and acoustic emissions (AEs) monitoring demonstrated that semi-brittle flow associated with AEs was dominant and the creep/failure strength of dunite was insensitive to the dissolved water content in olivine. In contrast, aqueous fluid drastically decreased the creep/failure strength of dunite (up to ~ 1 GPa of weakening) over a wide range of temperatures in the semi-brittle regime. Weakening of the dunite by the aqueous fluid resulted in the reduction of the number of AE events (i.e., suppression of microcracking) and shortening of time to failure. The AE hypocenters were located at the margin of the deforming sample while the interior of the faulted sample was aseismic (i.e., aseismic semi-brittle flow) under water-saturated conditions. A faulting (slip rate of ~ 10?³ to 10?? s?¹) associated with a large drop of stress (?? ~ 0.5 to 1 GPa) and/or pressure (?P ~ 0.5 GPa) was dominant in fluid-free dunite, while a slow faulting (slip rate < 8 × 10?? s?¹) without any stress/pressure drop was common in water-saturated dunite. Aseismic semi-brittle flow may mimic silent ductile flow under water-saturated conditions in subducting slabs.
DS201911-2534
2019
Higo, Y.Ishi, T., Huang, R., Myhill, R., Fei, H., Koemets, I., Liu, Z., Maeda, F., Yuan, L., Wang, L., Druzhbin, D., Yamamoto, T., Bhat, S., Farla, R., Kawazoe, T., Tsujino, N., Kulik, E., Higo, Y., Tange, H., Katsura, T.Sharp 660 km discontinuity controlled by extremely narrow binary post-spinel transition.Nature Geosciences, Vol. 12, pp. 869-872.Mantlediscontinuity

Abstract: The Earth’s mantle is characterized by a sharp seismic discontinuity at a depth of 660?km that can provide insights into deep mantle processes. The discontinuity occurs over only 2?km—or a pressure difference of 0.1?GPa—and is thought to result from the post-spinel transition, that is, the decomposition of the mineral ringwoodite to bridgmanite plus ferropericlase. Existing high-pressure, high-temperature experiments have lacked the pressure control required to test whether such sharpness is the result of isochemical phase relations or chemically distinct upper and lower mantle domains. Here, we obtain the isothermal pressure interval of the Mg-Fe binary post-spinel transition by applying advanced multi-anvil techniques with in situ X-ray diffraction with the help of Mg-Fe partition experiments. It is demonstrated that the interval at mantle compositions and temperatures is only 0.01?GPa, corresponding to 250?m. This interval is indistinguishable from zero at seismic frequencies. These results can explain the discontinuity sharpness and provide new support for whole-mantle convection in a chemically homogeneous mantle. The present work suggests that distribution of adiabatic vertical flows between the upper and lower mantles can be mapped on the basis of discontinuity sharpness.
DS1860-0109
1870
Higson, G.S.Higson, G.S.Diamonds and Gold at the CapeJournal of Society of Arts , Vol. 18, PP. 757-760.Africa, South Africa, Cape ProvinceAlluvial Placers
DS2002-1239
2002
Hihma, H.Peltonen, P., Kinnunen, K.A., Hihma, H.Petrology of two Diamondiferous eclogite xenoliths from the Lahtojoki kimberlite pipe, eastern Finland.Lithos, Vol. 63, pp. 151-164.FinlandPetrology, therombarometry, deformation, Deposit - Lahtojoki
DS201904-0797
2019
Hikll, G.Voigt, A., Morrison, G., Hikll, G., Dellas, G., Mngera, R.The application of XRT in the De Beers Group of Companies. The Southern African Institute of Mining and Metallurgy, Vol. 119, pp. 149-154.Africa, South Africamineral processing - XRT
DS200812-0955
2008
Hilairet, N.Reynard, B., Hilairet, N., Daniel, I., Wang, Y.Rheology of serpentines, seismicity and mass transfer in subduction zone.Goldschmidt Conference 2008, Abstract p.A789.MantleSubduction
DS201312-0792
2013
Hilairet, N.Schubnel, A., Brunet, F., Hilairet, N., Gasc, J., Wang, Y., Green, H.W.II.Deep focus earthquake analogs recorded at high pressure and temperature in the laboratory.Science, Vol. 341, no. 6152, pp. 1377-1380. Sept. 20TechnologySubduction
DS201312-0956
2013
Hilairet, N.Wang, Y., Hilairet, N., Nishiyama, N., Yahata, N., Tsuchiya, T., Morad, G., Fiquet, G.High pressure, high temperature deformation of CaGeO3 ( perovskite) +-MgO aggregates: implications for multiphase rheology of the lower mantle.Geochemistry, Geophysics, Geosystems: G3, Vol. 14, 9, pp. 3389-3408.MantlePerovskite
DS200412-0218
2004
Hilaret, N.Bromiley, G., Hilaret, N., McCammon, C.Solubility of hydrogen and ferris iron in rutile and TiO1(II): implications for phase assemblages during ultrahigh pressure metaGeophysical Research Letters, Vol. 31, 4, Feb. 28, DOI 1029/2004 GLO19430MantleSilica polymorphs in the lower mantle
DS1993-0932
1993
Hilborn, R.Ludwig, D., Hilborn, R., Walters, C.Uncertainty, resource exploitation, conservation: lessons from historyScience, Vol. 260, April 2, pp. 17, 36GlobalEconomics
DS201212-0198
2012
Hilchie, L.Fedortchouk, Y., Hilchie, L., McIssac, E.Diamond survival in kimberlite magma: the importance of fluid.10th. International Kimberlite Conference Feb. 6-11, Bangalore India, AbstractMantleDiamond genesis
DS201312-0385
2013
Hilchie, L.Hilchie, L.Variability of hydrogen zonation in olivines from kimberlites: possible relevance for diamond potential.GEM Diamond Workshop Feb. 21-22, Noted onlyGlobalDiamond inclusions
DS201312-0763
2013
Hilchie, L.Russell, J.K., Porritt, L.A., Hilchie, L.Kimberlite: rapid ascent of lithospherically modified carbonatitic melts.Proceedings of the 10th. International Kimberlite Conference, Vol. 1, Special Issue of the Journal of the Geological Society of India,, Vol.1, pp. 195-210.TechnologyGenesis - melts
DS201412-0356
2014
Hilchie, L.Hilchie, L., Fedortchouk, Y., Matveev, S., Kopylova, M.G.The origin of high hydrogen content in kimberlitic olivine: evidence from hydroxyl zonation in olivine from kimberlites and mantle xenoliths.Lithos, Vol. 202-203, pp. 429-441.Canada, Nunavut, Northwest Territories, Africa, LesothoDeposit - Jericho, Beartooth, Pipe 200, Matsoku
DS201901-0034
2018
Hilchie, L.Fulop, A., Kopylova, M., Kurszlaukis, S., Hilchie, L., Ellemers, P., Squibb, C.Petrography of Snap Lake kimberlite dyke ( Northwest Territories, Canada) and its interaction with country rock granitoids.Journal of Petrology, Vol. 59, 12, pp. 2493-2518.Canada, Northwest Territoriesdeposit - Snap Lake

Abstract: Carbonate-rich intrusions in contact with felsic rocks theoretically should show the effects of interaction between the two rock types, due to their contrasting compositions. In reality, though, such interaction is rarely reported at kimberlite contacts. We present the first documented case of lithological and mineralogical zonation at the margin of a kimberlite, the Snap Lake dyke, in contact with the wall-rock granitoid. Our detailed petrographic, mineralogical and geochemical study shows that the fresh hypabyssal kimberlite consists of olivine macrocrysts and microcrysts, and phlogopite macrocrysts set in a groundmass of serpentinized monticellite, phlogopite, spinel, perovskite and apatite, with interstitial lizardite and calcite. This typical Group I kimberlite mineralogy does not match the bulk-rock composition, which resembles a Group II micaceous kimberlite. The mismatch between the chemical and mineralogical properties is ascribed to contamination by granitoid xenoliths and metasomatic reactions with the felsic country rocks, the Snap Lake kimberlite has extremely low bulk-Ca compared to other documented Group I kimberlites. Reaction with deuteric H2O and CO2 has led to Ca removal, serpentinization of olivine, replacement of calcite by dolomite, alteration of perovskite and decomposition of apatite. Adjacent to the contact with the host granitoid and in haloes around granitoid clasts, poikilitic phlogopite and lizardite are replaced by subsolidus phlogopite and a multiphase phyllosilicate composed of phlogopite+?lizardite+?chlorite+?talc. A modified isocon analysis accounts for felsic xenolith assimilation and isolates metasomatic changes. Enrichment of altered kimberlites in Si owes solely to xenolith incorporation. The metasomatic ingress of granitoid-derived Al for a limited distance inside the dyke was counteracted by a flux of Mg and Fe to the granitoid. Metasomatic changes in K and Ca tend to be positive in all lithologies of kimberlite and in the granitoids implying distal transport. The combination of xenolith digestion with metasomatic element transport is expected in hybrid zones where kimberlite magmas interact with felsic wall-rocks.
DS201902-0286
2018
Hilchie, L.Kopylova, M.G., Fulop, A., Gaudet, M., Hilchie, L.Kimberlite skarns: more common and more complex.Goldschmidt Conference, 1p. AbstractMantlepetrology

Abstract: When carbonate-rich and silicate rocks are juxtaposed at high subsolidus temperature, their contrasting elemental chemical potentials trigger metasomatism. Kimberlites in contact with felsic-to-mafic rocks should theoretically develop skarn alteration, replacing both the wall rocks and magmatic rocks. Although some kimberlites are well exposed from mining, metasomatic effects in them are difficult to isolate because of the common presence of marginal country rock breccias and assimilated country rock xenoliths. The volatilerich nature of kimberlite melts and faulting prior to the emplacement results in country rock brecciation and incorporation of as much as 70% xenoliths in kimberlite. We discuss several examples of mineralogical, textural and chemical zonation at contacts between felsic-to-mafic xenoliths, in-situ country rocks and kimberlites (Renard, Gahcho Kue, Snap Lake and Orapa). The subsolidus skarn reactions are preceded by magmatic assimilation. It partially melts feldspars and forms diopside and phlogopite coronas on xenoliths. To distinguish between incorporation and assimilation of xenoliths and contact metasomatism, we employed an improved isocon analysis that enables estimation of metasomatic contributions to geochemical diversity. Skarn reactions replace the original kimberlite minerals with serpentine, phlogopite, hydrogarnet, while xenoliths are replaced by serpentine, clinopyroxene, carbonate, chlorite, and pectolite. If the mode of felsic-to-mafic xenoliths exceeds 30%, the textures and the mineralogy of the kimberlite altered by assimilation and skarn reactions may resemble those of the Kimberly-type pyroclastic kimberlite (KPK). The distinct mineralogy of the KPK interclast matrix, the correlation between xenolith modes and the kimberlite texture, the spatial distribution of KPK in Renard and Gahcho Kue kimberlites indicate the principal role of crustal xenoliths in the KPK formation. Our data suggest that metasomatic recrystallization of kimberlites is more widespread than previously recognized, but is complex and accompanied by xenolith assimilation.
DS201905-1031
2019
Hilchie, L.Fulop, A., Kopylova, M., Kurszlaukis, S., Hilchie, L., Ellemers, P.A reply to the comment by Germon et al. on the Petrography of the Snap Lake kimberlite dyke ( Northwest Territories, Canada) and its interaction with country rock granitoids.Journal of Petrology, Vol. 60, 3, pp. 661-671.Canada, Northwest Territoriesdeposit - Snap Lake
DS201803-0468
2018
Hilchie, L.J.Newton, D.E., Ryan, A.G., Hilchie, L.J.Competence and lithostratigraphy of host rocks govern kimberlite pipe morphology.Canadian Journal of Earth Science, Vol. 55, pp. 130-137.GlobalKimberlite morphology

Abstract: We use analogue experimentation to test the hypothesis that host rock competence primarily determines the morphology of kimberlite pipes. Natural occurrences of kimberlite pipes are subdivided into three classes: class 1 pipes are steep-sided diatremes emplaced into crystalline rock; class 2 pipes have a wide, shallow crater emplaced into sedimentary rock overlain by unconsolidated sediments; class 3 pipes comprise a steep-sided diatreme with a shallow-angled crater emplaced into competent crystalline rock overlain by unconsolidated sediments. We use different configurations of three analogue materials with varying cohesions to model the contrasting geological settings observed in nature. Pulses of compressed air, representing the energy of the gas-rich head of a kimberlitic magma, are used to disrupt the experimental substrate. In our experiments, the competence and configuration of the analogue materials control the excavation processes as well as the final shape of the analogue pipes: eruption through competent analogue strata results in steep-sided analogue pipes; eruption through weak analogue strata results in wide, shallow analogue pipes; eruption through intermediate strength analogue strata results in analogue pipes with a shallow crater and a steep-sided diatreme. These experimental results correspond with the shapes of natural kimberlite pipes, and demonstrate that variations in the lithology of the host rock are sufficient to generate classic kimberlite pipe shapes. These findings are consistent with models that ascribe the pipe morphologies of natural kimberlites to the competence of the host rocks in which they are emplaced.
DS2000-0115
2000
Hildebrand, A.R.Brown, P.G., Hildebrand, A.R., Mazur, T.R.The fall, recovery, orbit and composition of the Taglish Lake meteorite: A new type of carbonaceous..Science, Vol. 290, No. 5490, Oct. 13, pp. 320-4.Northwest TerritoriesChondrites
DS2003-0524
2003
Hildebrand, P.Gurney, J.J., Hildebrand, P., Carlson, J., Dyke, D., Fedortchouk, Y.Diamonds from the Ekati core and buffer zone properties8 Ikc Www.venuewest.com/8ikc/program.htm, Session 3, AbstractNorthwest TerritoriesDiamonds - inclusions, Deposit - Ekati
DS200412-0752
2003
Hildebrand, P.Gurney, J.J., Hildebrand, P., Carlson, J., Dyke, D., Fedortchouk, Y.Diamonds from the Ekati core and buffer zone properties.8 IKC Program, Session 3, AbstractCanada, Northwest TerritoriesDiamonds - inclusions Deposit - Ekati
DS1995-0794
1995
Hildebrand, P.R.Hildebrand, P.R., Gurney, J.J.Lithosphere evolution in rifted, craton and mobile belt environments from Zimbabwe and diamond prospectivity.Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 236-238.ZimbabweTectonics, Craton, Limpopo Belt
DS200412-0753
2004
Hildebrand, P.R.Gurney, J.J., Hildebrand, P.R., Carlson, J.A., Fedortchouk, Y., Dyck, D.R.The morphological characteristics of diamonds from the Ekati property, Northwest Territories, Canada.Lithos, Vol. 77, 1-4, Sept. pp. 21-38.Canada, Northwest TerritoriesDiamond morphology, colour
DS1995-0795
1995
Hildebrand, R.S.Hildebrand, R.S.The origin of Diamondiferous kimberlitesGeological Society of America (GSA) Abstracts, Vol. 27, No. 6, abstract p. A 119.Northwest Territories, ColoradoKimberlites, Genesis
DS1999-0307
1999
Hildebrand, R.S.Hildebrand, R.S., Bowring, S.A.Crustal recycling by slab failureGeology, Vol. 27, No. 1, Jan. pp. 11-14.Northwest TerritoriesTectonics, Wopmay orogen, Morel Sills, Subduction, slab
DS2003-0582
2003
Hildebrand, R.S.Hildebrand, R.S.Evolution of arc continent collision in Wopmay orogen, northwestern Canada:upperGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p.344.Northwest TerritoriesTectonics
DS200412-0826
2003
Hildebrand, R.S.Hildebrand, R.S.Evolution of arc continent collision in Wopmay orogen, northwestern Canada:upper plate extension to lower plate breakoff,Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p.344.Canada, Northwest TerritoriesTectonics
DS1995-0796
1995
Hildebrandt, S.Hildebrandt, S., Tromba, A.The parsimonious universe... shape and form in the natural worldSpringer, 328p. approx. $ 35.00GlobalBook -ad, Universe - shape and forM.
DS200512-0434
2005
HildenbrandHinze, W.J., Aiken, C., Brozena, J., Coakley, Dater, Flanagan, Forsberg, Hildenbrand, Keller, KelloggNew standards for reducing gravity data: the North American gravity database.Geophysics, Vol. 70, 4, pp. J25-J32.Canada, United StatesGeophysics - gravity
DS200612-0675
2006
HildenbrandKeller, G.R., Hildenbrand, Kucks, Webring, Briesacher, Rujawitz, Hittleman, Roman, Winester, Aldouri et al.A community effort to construct a gravity database for the United States and an associated Web portal.In: Sinha, A.K. Geoinformatics: data to knowledge, GSA Special Paper, 397, 397, pp.21-34 rUnited StatesGeophysics - gravity data
DS2003-1408
2003
Hildenbrand, P.Van Coller, B., Hildenbrand, P., Verran, D., Barnes, F., Nowicki, T.E.Southern African case studies of variations in indicator mineral characteristics with8 Ikc Www.venuewest.com/8ikc/program.htm, Session 8, POSTER abstractSouth AfricaBlank
DS200412-2034
2003
Hildenbrand, P.Van Coller, B., Hildenbrand, P., Verran, D., Barnes, F., Nowicki, T.E., Baumgartner, M., Ott, L., Gurney, J.J.Southern African case studies of variations in indicator mineral characteristics with distance from kimberlite source.8 IKC Program, Session 8, POSTER abstractAfrica, South AfricaDiamond exploration
DS1975-0527
1977
Hildenbrand, T.G.Hildenbrand, T.G., Kane, M.F., Stauder, W.Magnetic and Gravity Anomalies in the Northern Mississippi Embayment and Their Spatial Relation to Seismicity.United States Geological Survey (USGS) miscellaneous FIELD MAP, No. MF-914, 1:1, 000, 000.GlobalMid-continent
DS1975-0831
1978
Hildenbrand, T.G.O'leary, D.W., Hildenbrand, T.G.Structural Significance of Lineament and Aeromagnetic Patterns in the Mississippi Embayment.Proceedings THIRD International CONFERENCE ON BASEMENT TECTONICS, BASEMENT TECTONICS COMMITTEE No. 3, PP. 305-313.GlobalMid-continent
DS1975-1085
1979
Hildenbrand, T.G.Johnson, R.W.JR., Hildenbrand, T.G., Haygood, C., Kunselman, P.Magnetic Anomaly Map of the Greater New Madrid Seismic ZoneEos, Vol. 61, No. 5, PP. 47-48. (abstract.).GlobalMid-continent
DS1980-0174
1980
Hildenbrand, T.G.Hildenbrand, T.G., Kucks, R.P., Kane, M.F., Hendricks, J.D.Aeromagnetic Map and Associated Depth Map of the Upper Mississippi Embayment Region.United States Geological Survey (USGS) miscellaneous FIELD MAP, No. MF-1158, 1: 1, 000, 000.GlobalMid-continent
DS1981-0232
1981
Hildenbrand, T.G.Kane, M.F., Hildenbrand, T.G., Hendricks, J.D.A Model for the Tectonic Evolution of the Mississippi Embayment and its Contempory Seismicity.Geology, Vol. 9, No. 12, PP. 563-568.GlobalMid-continent
DS1982-0275
1982
Hildenbrand, T.G.Hildenbrand, T.G.Magnetic Terrane in the Central U.s. from Interpretation Of digital Magnetic Data.Geophysics, Vol. 48, No. 4, P. 451. (abstract.).GlobalMid-continent
DS1982-0276
1982
Hildenbrand, T.G.Hildenbrand, T.G.Model of the Southeastern Margin of the Mississippi Valley Graben Near Memphis Tennessee from Interpretation of Truck Magnetometer Data.Geology, Vol. 10, No. 9, PP. 476-480.GlobalMid-continent, Geophysics, Mississippi Embayment, Pluton
DS1982-0277
1982
Hildenbrand, T.G.Hildenbrand, T.G., Kane, M.F., Hendricks, J.D.Magnetic Basement in the Upper Mississippi Embayment Region-a Preliminary Report.United States Geological Survey (USGS) PROF. PAPER., No. 1236-E.GlobalMid-continent
DS1983-0304
1983
Hildenbrand, T.G.Hildenbrand, T.G., Keller, G.R.Magnetic and Gravity Features of Western Kentucky; Their Geologic Significance.United States Geological Survey (USGS) OPEN FILE., No. 83-0164, 13P. 1 MAP 1:500, 000.GlobalMid Continent
DS1985-0287
1985
Hildenbrand, T.G.Hildenbrand, T.G.Rift structure of the northern Mississippi Embayment from the analysis of gravity and magnetic dataJournal of Geophysical Research, Vol. 90, No. B14, Dec. 10, pp. 12, 607-12, 622Midcontinent, TennesseeGeophysics, Tectonics
DS1987-0293
1987
Hildenbrand, T.G.Hildenbrand, T.G.Magnetic and gravity features of central United StatesGeological Society of America, Vol. 19, No. 4, March p. 203-204. (abstract)United StatesMidcontinent, Geophysics
DS1991-1591
1991
Hildenbrand, T.G.Sims, P.K., Peterman, Z.E., Hildenbrand, T.G., Mahan, S.Precambrian basement map of the Trans-Hudson Orogen and adjacent northern Great Plains, United States (US)United States Geological Survey (USGS), Map I 2214, 1: 1, 000, 000 $ 3.10Minnesota, Montana, Nebraska, WyomingPrecambrian, Map
DS1995-0797
1995
Hildenbrand, T.G.Hildenbrand, T.G., et al.Crustal geophysics gives insight into New Madrid seismic zoneEos, Vol. 76, No. 7, Feb. 14, p. 65, 68, 69.Arkansas, midcontinentGeophysics -seismics, Tectonics
DS1995-0798
1995
Hildenbrand, T.G.Hildenbrand, T.G., Hendricks, J.D.Geophysical setting of the Reelfoot Rift and relations between rift structures and the New Madrid seismic zoneUnited States Geological Survey (USGS) Paper, No. 1538-E, 30p. $ 3.50Arkansas, Missouri, Midcontinent, MississippiGeophysics -seismics, Tectonics, Mid continent Rift
DS1995-0799
1995
Hildenbrand, T.G.Hildenbrand, T.G., Hendricks, J.D.Geophysical setting of the Reelfoot Rift and relations bewteen rift structures and the New Madrid seismic zoneUnited States Geological Survey (USGS) Paper, No. 1538-E, 30p. $ 3.50Missouri, Arkansas, Tennessee, KentuckyTectonics, Mid continent rifting
DS1995-0800
1995
Hildenbrand, T.G.Hildenbrand, T.G., Jachens, R.C., Simpson, R.W.Insights on lithospheric structures within the stable craton, USA based on magnetic and gravity data.Iagod Giant Ore Deposits Workshop, J. Kutina, 6p.MidcontinentCraton, Geophysics -magnetics, gravity
DS1996-0629
1996
Hildenbrand, T.G.Hildenbrand, T.G., Blakely, R.J., Hinze, W.J., et al.Aeromagnetic survey over the U.S. to advance geomagnetic researchEos, Vol. 77, No. 28, July 9, pp. 265, 268United StatesGeophysics -aeromagnetics, Brief overview
DS1997-0505
1997
Hildenbrand, T.G.Hildenbrand, T.G., Jachens, R.C., Simpson, R.W.Insights on lithospheric structures within the stable craton USA, based on magnetic and gravity data.Global Tectonics and Metallogeny, Vol. 6, No. 2, March pp. 113-118.MidcontinentMantle structure, Geophysics - magnetics, gravity
DS1997-0649
1997
Hildenbrand, T.G.Langerheim, V.E., Hildenbrand, T.G.Commerce geophysical lineament - its source, geometry and relationship to Reelfoot Rift and New Madrid zone.Geological Society of America (GSA) Bulletin., Vol. 109, No. 5, May pp. 580-595.Arkansas, Tennessee, Kentucky, MissouriTectonics, Rifting
DS1997-1118
1997
Hildenbrand, T.G.Stuart, W.D., Hildenbrand, T.G., Simpson, R.W.Stressing of the New Madrid seismic zone by a lower crust detachmentfault.Journal of Geophysical Research, Vol. 102, No. 12, Dec. 10, pp. 27, 623-34.Midcontinent, Minnesota, WisconsinGeophysics, New Madrid Seismic Zone
DS2003-0583
2003
Hildenbrand, T.G.Hildenbrand, T.G., Keller, R.G., Blakely, R., Hinze, W.J.Need for a U.S. high altitude magnetic surveyGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 446.United StatesGeophysics
DS2003-0896
2003
Hildenbrand, T.G.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois Basin and itsTectonophysics, Vol. 363, 1-2, Feb. 20, pp. 45-78.IllinoisGeophysics - seismics, Tectonics
DS2003-0897
2003
Hildenbrand, T.G.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois basin and itsTectonophysics, Vol. 363, No. 1-2, Feb. 20, pp. 45-78.Illinois, IndianaGeophysics - seismics, New Madrift Rift system, Reelfoot Rift, Rough Creek Gra
DS200412-0827
2003
Hildenbrand, T.G.Hildenbrand, T.G., Keller, R.G., Blakely, R., Hinze, W.J.Need for a U.S. high altitude magnetic survey.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 446.United StatesGeophysics
DS200412-1254
2003
Hildenbrand, T.G.McBride, J.H., Kolata, D.R., Hildenbrand, T.G.Geophysical constraints on understanding the origin of the Illinois Basin and its underlying crust.Tectonophysics, Vol. 363, 1-2, Feb. 20, pp. 45-78.United States, IllinoisGeophysics - seismics Tectonics
DS200512-0431
2004
Hildes, D.Hildes, D.Kimberlite exploration using a capacitively-coupled resistivity system.32nd Yellowknife Geoscience Forum, Nov. 16-18, p.33-34. (poster)Canada, Northwest TerritoriesGeophysics - resistivity
DS200712-0855
2007
Hildes, D.Power, M., Hildes, D.Geophysical strategies for kimberlite exploration in northern Canada.Proceedings of Exploration 07 edited by B. Milkereit, pp. 1025-1031.Canada, Northwest TerritoriesGeophysics - diamond - review
DS2003-0559
2003
Hildreth, W.Hart, G.L., Johnon, C.M., Hildreth, W., Shirey, S.B.New osmium isotope evidence for intracrustal recycling of crustal domains with discreteGeology, Vol. 31, 5, pp. 427-30.mantleGeochronology
DS200412-0801
2003
Hildreth, W.Hart, G.L., Johnon, C.M., Hildreth, W., Shirey, S.B.New osmium isotope evidence for intracrustal recycling of crustal domains with discrete ages.Geology, Vol. 31, 5, pp. 427-30.TechnologyMantle Geochronology
DS1993-0148
1993
Hilebrand, R.S.Bowring, S.A., Housh, T.B., Isachsen, Hilebrand, R.S.What do we know about the western limit of the Slave craton?Northwest Territories Exploration Overview for 1993, November p. 24.Northwest TerritoriesCraton, Slave Craton
DS1997-0506
1997
Hilgen, F.J.Hilgen, F.J., Krijgsman, W., Langereis, C.G., Lourens, L.Breakthrough made in dating of the geological recordEos, Vol. 78, No. 28, July 15, p. 285, 288, 289GlobalTimescale, Sedimentary cycles
DS201705-0834
2017
Hilgner, A.Hilgner, A., Greiff, S., Quast, D.Gemstones in the first millennium AD. Mines, trade, workshops and symbolism. Romisch-Germanisches Zentralmuseum Leibniz-Forschungsinstitut fur Archaologie Mainz International Conference Oct. 20-22, 2015, pp. 155-217.GlobalBook - gemstones
DS1998-0135
1998
HilgrenBoehler, R., Zerr, A., Serghiou, Tschauner, HilgrenNew experimental constraints on the nature of DMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 182-3.MantleCore mantle boundary layer, Perovskite
DS2002-0179
2002
Hilgren, V.Boehler, R., Chudinovskikh, L., Hilgren, V.Earth's core and lower mantle: phase behaviour melting and chemical interactionsProceedings - International School of Physics Enrico Fermi, Vol. 147, pp. 627-42. Ingenta 1025439480MantleMelt
DS1991-1257
1991
HillOliver, N.H.S., Holcombe, Hill, PearsonTectono-metamorphic evolution of the Mary Kathleen fold belt: a reflection of mantle plume processes?Australian Journal of Earth Sciences, Vol. 38, No. 4, pp. 425-55.AustraliaCrustal evolution - not specific to diamond
DS2002-1456
2002
HillShearer, S., Bankey, Hill, Finn, Daniels, Snyder, RobertsUnited States aeromagnetic database: a companion to the North American magnetic anomaly map.Geological Society of America Annual Meeting Oct. 27-30, Abstract p. 387.United States, CanadaMap - magnetic
DS2001-0109
2001
Hill, B.M.Bickford, M.E., Hamilton, M.A., Wortman, G., Hill, B.M.Archean rocks in the southern Rottenstone Domain: significance for the evolution of Trans Hudson OrogenCanadian Journal of Earth Sciences, Vol. 38, No. 7, July pp. 1017-25.Saskatchewan, ManitobaGeochronology, Trans Hudson orogeny
DS2001-0478
2001
Hill, B.M.Hill, B.M., Bickford, M.E.Paleoproterozoic rocks of central Colorado: accreted arcs or extended older crustGeology, Vol. 29, No. 11, Nov. pp. 1015-18.ColoradoGeochronology, Tectonics, Laurentia
DS201903-0532
2019
Hill, D.J.Mills, B.J.W., Krause, A.J., Scotese, C.R., Hill, D.J., Shields, G.A., Lenton, T.M.Modelling the long term carbon cycle, atmospheric CO2, and Earth surface temperature from late Neoproterozoic to present day.Gondwana Research, Vol. 67, pp. 172-186.Mantlecarbon

Abstract: Over geological timescales, CO2 levels are determined by the operation of the long term carbon cycle, and it is generally thought that changes in atmospheric CO2 concentration have controlled variations in Earth's surface temperature over the Phanerozoic Eon. Here we compile independent estimates for global average surface temperature and atmospheric CO2 concentration, and compare these to the predictions of box models of the long term carbon cycle COPSE and GEOCARBSULF. We find a strong relationship between CO2 forcing and temperature from the proxy data, for times where data is available, and we find that current published models reproduce many aspects of CO2 change, but compare poorly to temperature estimates. Models are then modified in line with recent advances in understanding the tectonic controls on carbon cycle source and sink processes, with these changes constrained by modelling 87Sr/86Sr ratios. We estimate CO2 degassing rates from the lengths of subduction zones and rifts, add differential effects of erosion rates on the weathering of silicates and carbonates, and revise the relationship between global average temperature changes and the temperature change in key weathering zones. Under these modifications, models produce combined records of CO2 and temperature change that are reasonably in line with geological and geochemical proxies (e.g. central model predictions are within the proxy windows for >~75% of the time covered by data). However, whilst broad long-term changes are reconstructed, the models still do not adequately predict the timing of glacial periods. We show that the 87Sr/86Sr record is largely influenced by the weathering contributions of different lithologies, and is strongly controlled by erosion rates, rather than being a good indicator of overall silicate chemical weathering rates. We also confirm that a combination of increasing erosion rates and decreasing degassing rates over the Neogene can cause the observed cooling and Sr isotope changes without requiring an overall increase in silicate weathering rates. On the question of a source or sink dominated carbon cycle, we find that neither alone can adequately reconstruct the combination of CO2, temperature and strontium isotope dynamics over Phanerozoic time, necessitating a combination of changes to sources and sinks. Further progress in this field relies on >108?year dynamic spatial reconstructions of ancient tectonics, paleogeography and hydrology. Whilst this is a significant challenge, the latest reconstruction techniques, proxy records and modelling advances make this an achievable target.
DS1975-0528
1977
Hill, D.R.H.Hill, D.R.H.Field Relationships and Petrography of the Kimberlite Sill sand Associated Dykes at the 40 Metre Level of the Wesseltonmine, Kimberley, South Africa.Bsc. Thesis, Honours, University of Cape Town., South AfricaKimberlite, Mineralogy, Petrology
DS1987-0294
1987
Hill, E.Hill, E., Barnes, C.G.Slickrock Mountain intrusive complex, Big Bend National Park, TexasMantle metasomatism and alkaline magmatism, edited E. Mullen Morris and, No. 215, pp. 305-316GlobalAnalyses p. 315
DS2000-0410
2000
Hill, E.Hill, E., Wood, B.J., Blundy, J.D.The effect of Ca Tschermaks component on trace element partitioning between clinopyroxene and silicate melt.Lithos, Vol. 53, No. 3-4, Sept. 1, pp. 203-15.GlobalPetrology - experimental, Clinopyroxene
DS2000-0411
2000
Hill, E.Hill, E., Wood, B.J., Blundy, J.D.The effect of Ca Tschermaks component on trace element partioning between clinopyroxene and silicate melt.Lithos, Vol. 53, No. 3-4, Sept. pp. 203-15.GlobalPetrology - experimental, Mineralogy - clinopyroxene
DS2001-0653
2001
Hill, E.Landwehr, D., Blundy, J., Chamorro-Perez, Hill, E., WoodU series disequilibration temperatures generated by partial melting of spinel lherzoliteEarth and Planetary Science Letters, Vol. 188, No. 3-4, pp. 329-48.MantleMelting, lherzolite
DS202102-0197
2021
Hill, E.J.Hill, E.J., Pearce, M.A., Stromberg, J.M.Improving automated geological logging of drill holes by incorporating multiscale spatial methods. ( not specific to diamonds)Mathematical Geosciences, Vol. 53, pp. 21-53. pdfGlobaldrill hole data

Abstract: Manually interpreting multivariate drill hole data is very time-consuming, and different geologists will produce different results due to the subjective nature of geological interpretation. Automated or semi-automated interpretation of numerical drill hole data is required to reduce time and subjectivity of this process. However, results from machine learning algorithms applied to drill holes, without reference to spatial information, typically result in numerous small-scale units. These small-scale units result not only from the presence of very small rock units, which may be below the scale of interest, but also from misclassification. A novel method is proposed that uses the continuous wavelet transform to identify geological boundaries and uses wavelet coefficients to indicate boundary strength. The wavelet coefficient is a useful measure of boundary strength because it reflects both wavelength and amplitude of features in the signal. This means that boundary strength is an indicator of the apparent thickness of geological units and the amount of change occurring at each geological boundary. For multivariate data, boundaries from multiple variables are combined and multiscale domains are calculated using the combined boundary strengths. The method is demonstrated using multi-element geochemical data from mineral exploration drill holes. The method is fast, reduces misclassification, provides a choice of scales of interpretation and results in hierarchical classification for large scales where domains may contain more than one rock type.
DS1900-0560
1907
Hill, F.D.Hill, F.D.Diamond Mining; July, 1907Engineering and Mining Journal, Vol. 84, JULY 27TH. PP. 151-152. ALSO: U.S. DAILY CONS. TRADAfrica, South AfricaMining
DS1997-0256
1997
Hill, F.J.Dawson, J.B., Hill, F.J.Nephelinite natrocarbonatite relationships at Oldoinyo Lengai, TanzaniaGeological Association of Canada (GAC) Abstracts, TanzaniaCarbonatite, Deposit - Oldoinyo Lengai
DS201807-1535
2018
Hill, G.Voigt, A., Morrison, G., Hill, G., Dellas, G., Mangera, R.The application of XRT in the De Beers Group of Companies. Jwaneng, marineSAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13., pp. 173-184.Africa, Botswana, NamibiaXRT sorters
DS201808-1795
2018
Hill, G.Voight, A., Morrison, G., Hill, G., Dellas, G., Mangera, R.The application of XRT in the De Beers Group of Companies. PresentationSAIMM Diamonds - source to use 2018 Conference 'thriving in changing times'. June 11-13., 25 ppts.GlobalMining - XRT
DS2000-0508
2000
Hill, H.Kletetschka, G., Taylor, P.T., Wasilewski, P., Hill, H.Magnetic properties of aggregate polycrystalline diamond: implications for carbonado history.Earth and Planetary Science Letters, Vol.181, No.3, Sept.15, pp.279-90.Central African Republic, Brazil, BahiaCarbonado, Genesis
DS201312-0144
2013
Hill, I.Chambers, J.E., Wilkinson, P.B., Wrdrop, D., Hameed, A., Hill, I., Jeffrey, C., Loke, M.H., Meldrum, P.I., Kuras, O., Cave, M., Gunn, D.A.Bedrock detection beneath river terrace deposits using three dimensional electrical resistivity tomography.Geomorphology, Vol. 177-178, pp. 17-25.GlobalGeochronology
DS1859-0020
1809
Hill, J.Hill, J.Translation of Theophrastus's Tract on GemsPhil. Transactions Royal Society of London., Vol. 9, P. 200.GlobalGemology
DS1993-0667
1993
Hill, J.H.Hill, J.H.Factors relevant to negotiations in RussiaMineral Industry International, No. 1010, January pp. 4-6RussiaEconomics, Brief overview joint-venture
DS1993-0668
1993
Hill, J.H.Hill, J.H.Factors relevant to negotiating in RussiaMinerals Industry International ( Institute of Mining and Metallurgy (IMM) Newsletter), January No. 1010, pp 4-6RussiaEconomics, Contracts
DS1993-0669
1993
Hill, J.H.Hill, J.H.Russian mining lawMinerals Industry International, No. 1014, September pp. 3-21RussiaLegal, Mining laws -explained and outlined
DS1993-0670
1993
Hill, J.H.Hill, J.H.Russian move welcome... central isation of control of the Russian diamondindustryMinerals Industry International, No. 1014, September pp. 3-21.RussiaLegal, Mining laws -explained and outlined
DS1988-0304
1988
Hill, J.R.Hill, J.R.Gold and diamonds in Indiana: an updateIndiana Geological Survey Circular, No. 12, 56p. $ 2.00IndianaOverview, Diamond history
DS200412-0828
2004
Hill, K.C.Hill, K.C., Hall, R.Mesozoic - Cenozoic evolution of Australia's New Guinea margin in a west Pacific context.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 265-290.AustraliaTectonics
DS201212-0122
2012
Hill, L.Chambers, J.E., Wilkinson, P.B., Wardrop, D., Hameed, A., Hill, L., Jeffrey, C., Loke, Mledrum, Kuras, Cave, GunnBedrock detection beneath river terrace deposits using three dimensional electrical resistivity tomography.Geomorphology, Vol. 177-178, pp. 7-25.TechnologyTomography - not specific to diamonds
DS1970-0534
1972
Hill, M.Hill, M.Hunting Diamonds in CaliforniaHealdsburg Calif.: Naturegraph Publishing, Pages of History, Saus, 80 P.; 1ST. EDITION, 1959.United States, California, West CoastKimberlite
DS200412-0767
2004
Hill, M.J.Halls, H.C., McArdle, N.J., Gratton, M.N., Hill, M.J., Shaw, J.Microwave paleointensities from dyke chilled margins: a way to obtain long term variations in geodynamo intensity for the last tPhysics of the Earth and Planetary Science Interiors, Vol. 147, 2-3, Nov. 15, pp.183-195.Canada, OntarioMattachewan dyke swarm, geochronology, Biscotasing, Mar
DS1994-0772
1994
Hill, N.R.Hill, N.R.Uganda: an opportunity for mineral productsIndustrial Minerals, No. 319, April pp. 119-125UgandaCountry profile, Industrial minerals
DS201604-0617
2016
Hill, P.Ladenburger, S., Marks, M.A.W., Upton, B., Hill, P., Wenzel, T., Markl, G.Compositional variation of apatite from rift related alkaline igneous rocks of the Gardar Province, South Greenland.American Mineralogist, Vol. 101, pp. 612-626.Europe, GreenlandAlkalic

Abstract: Textural and compositional variations of apatite from four intrusions with different characteristic features of the rift-related alkaline Gardar Province were investigated: dyke rocks that belong to the most primitive rocks of the Province (Isortoq), nepheline-syenites associated with a carbonatite (Grønnedal-Ika), SiO2-saturated and SiO2-oversaturated syenites (Puklen) and nepheline-syenites displaying the transition from miaskitic to agpaitic mineral assemblages (Motzfeldt, Fig.1). Additionally, apatites from these intrusions were compared with other apatites of the Gardar Province. These include apatites from the Older Giant Dyke Complex, the Younger Giant Dyke Complex (both from the Tugtutôq region) and a narsarsukite-bearing trachytic dyke (Igdlutalik), as well as apatites from the Kûngnât, the North Qôroq and the Ilímaussaq intrusive complexes. This results in a complete overview of rift-related magmatites of the Gardar Province, ranging from primitive to highly evolved rocks. Backscattered electron images reveal the presence of various types of apatite textures including (i) growth zonation (concentric and oscillatory) that formed during magmatic differentiation and (ii) overgrowth and secondary textures (rounded cores, patchy zonation and overgrowth rims) due to fluid/melt induced metasomatic overprint and intracrystalline diffusion (Fig.2). Additionally, apatite compositions were analyzed with wavelength-dispersive electron microprobe analyses. During the crystallization history of the different intrusions, as well as within samples (documented by zoning patterns), increasing concentrations are observed for Si, REE, Na and F, whereas Cl shows a decreasing trend. However, for F, Cl and Na these trends are only observed in dyke rocks. Compositional variation of the investigated apatites is mainly due to substitution of Ca and P by variable amounts of Si, Na and REE. This study reveals that variations in the chemical composition of apatite are useful tools to obtain geochemical information about the host magma and its magmatic evolution. Here, Si and REE were found to be reliable petrogenetic indicators, whereas Na, F and Cl are only applicable in fast cooling systems to avoid redistribution of those elements.
DS1998-0316
1998
Hill, P.G.Dawson, J.B., Hill, P.G.Mineral chemistry of a peralkaline cambeite lamprophyllite nephelinite from Oldoinyo Langai.Mineralogical Magazine, Vol. 62, No. 2, Apr. pp. 179-196.TanzaniaMineralogy, Carbonatite
DS2001-0235
2001
Hill, P.G.Dawson, J.B., Hill, P.G., Kinny, P.D.Mineral chemistry of a zircon bearing, composite veined and metasomatised upper mantle peridotite xenolith.Contributions to Mineralogy and Petrology, Vol. 140, No. 6, pp. 720-33.South AfricaKimberlite, Geochemistry
DS200412-0477
2004
Hill, P.G.Downes, H., Macdonald, R., Upton, B.G.J., Cox, K.G., Bodinier, J-L., Mason, P.R.D., James, D., Hill, P.G., HeaUltramafic xenoliths from the Bearpaw Mountains, Montana: USA: evidence for multiple metasomatic events in the lithospheric mantJournal of Petrology, Vol. 45, 8, pp. 1631-1662.United States, MontanaMetasomatism
DS1994-0117
1994
Hill, P.J.Bast, J.L., Hill, P.J.Eco-sanity: a common sense guide to environmentalisMMadison Books, GlobalBook -ad, EnvironmentalisM.
DS201503-0149
2015
Hill, P.J.A.Hill, P.J.A., Kopylova, M., Russell, J.K.Mineralogical controls on garnet composition in the cratonic mantle.Contributions to Mineralogy and Petrology, Vol. 169, 20p.MantleGarnet mineralogy
DS201603-0391
2016
Hill, P.J.A.Kopylova, M., Hill, P.J.A., Russell, J.K., Cookenboo, H.Lherzolitic versus harzburgitic garnet trends: sampling of extended depth versus extended composition: Reply to comments by Ivanic et al. 2015Contributions to Mineralogy and Petrology, Vol. 171, 2p.MantleHarzburgite

Abstract: Using the Hill et al. (Contrib Mineral Petrol 169:13, 2015. doi:10.1007/s00410-014-1102-7) modeling technique, we have tested the idea of Ivanic et al. (Contrib Mineral Petrol 164:505-520, 2012) that decompression and metamorphic re-equilibration of garnet with spinel causes garnet zoning perpendicular to the Cr-Ca harzburgitic trend in garnet composition. The modeling confirms that garnet zoning across the harzburgitic trend cannot form without spinel buffering. The harzburgitic trend is very rare because it results from extreme compositional heterogeneity of the mantle at the same depth. In contrast, the common lherzolitic trend requires less diversity in the bulk composition of the mantle, as it can be established with only a few samples of metamorphically re-equilibrated mantle peridotite deriving from a variety of depths.
DS1992-0725
1992
Hill, P.L.Hoover, D.B., Heran, W.D., Hill, P.L.The geophysical expression of selected mineral deposit modelsUnited States Geological Survey (USGS) Open File, No. 92-557, 140pUnited StatesGeophysics, Deposits
DS1996-0630
1996
Hill, P.R.Hill, P.R.Late Quaternary sequence stratigraphy of the Mackenzie DeltaCanadian Journal of Earth Sciences, Vol. 33, No. 7, July pp. 1064-1074.Northwest TerritoriesGeomorphology, Glacial history
DS200712-1139
2006
Hill, R.Wei, Z., Moldowan, J.M., Jarvie, D.M., Hill, R.The fate of diamondoids in coals and sedimentary rocks.Geology, Vol. 34, 12, pp. 1013-1016.TechnologyDiamondoids
DS1988-0305
1988
Hill, R.E.T.Hill, R.E.T., Gole, M.J., Barnes, S.J.Physical volcanology of komatiites. a field guide to the komatiites between Kalgoorlie and Wiluna, Eastern Gold fields Province, Yilgarn Block, WesternAustraliaGsa Western Australia Excursion Guidebook, No. 1, 74pAustraliaGuidebook, Komatiites
DS1993-1077
1993
Hill, R.E.T.Morris, P.A., Barnes, S.J., Hill, R.E.T.Eruptive environments and geochemistry of Archean ultramafic, mafic and felsic volcanic rocks of the eastern Yilgarn CratonAustralia Geological Survey AGSO, Record No. 1993/62, $ 16.95AustraliaVolcanics, Yilgarn Craton
DS1995-0105
1995
Hill, R.E.T.Barnes, S.J., Hill, R.E.T.Poikilitic chromite in komatiitic cumulatesMineralogy and Petrology, Vol. 54, No. 1-2, pp. 85-92AustraliaKomatiites
DS1995-0801
1995
Hill, R.E.T.Hill, R.E.T., Barnes, S.J., Gole, M.J., Dowling, S.E.The volcanology of komatiites as deduced from field relationships in the Norseman-Wiluna greenstone beltLithos, Vol. 34, No. 1-3, Jan. pp. 159-188AustraliaKomatiites, Norseman greenstone belt
DS1995-1485
1995
Hill, R.E.T.Perring, C.S., Barnes, S.J., Hill, R.E.T.The physical volcanology of Archean komatiite sequences from Forrestania, Southern Cross Province, Western AusLithos, Vol. 34, No. 1-3, Jan. pp. 189-208AustraliaKomatiites, Archean
DS1996-1111
1996
Hill, R.E.T.Perring, C.S., Barnes, S.J., Hill, R.E.T.Geochemistry of komatiites from Forrestania,Southern Cross Province:evidence for crustal contaminationLithos, Vol. 37, No. 2/3, April pp. 181-198AustraliaGeochemistry, Komatiites -Forrestania
DS1989-0202
1989
Hill, R.I.Campbell, I.H., Griffiths, R.W., Hill, R.I.Melting in an Archean mantle plume: heads it's basalts, tails it'skomatiitesNature, Vol. 339, No. 6227, June 29, pp. 697-698.Database#18086GlobalKomatiite, Mantle
DS1989-0640
1989
Hill, R.I.Hill, R.I., Campbell, I.H., Compston, W.Age and origin of granitic rocks in the Kalgoorlie-Norseman region Of western Australia: implications for the origin of Archean crustGeochimica et Cosmochimica Acta, Vol. 53, pp. 1259-1275. Database # 17955AustraliaGeochronology, Granitic -origin
DS1991-0713
1991
Hill, R.I.Hill, R.I.Starting plumes and continental break-upEarth and Planetary Science Letters, Vol. 104, pp. 398-416GlobalHot spots, Fluid dynamics, experimental petrology
DS1991-0714
1991
Hill, R.I.Hill, R.I., Campbell, I.H., Griffiths, R.W.Plume tectonics and the development of stable continental crustAustralian Society of Exploration Geophysicists and Geological Society of, Vol. 22, No. 1, March pp. 185-188AustraliaMantle, Plumes
DS1992-0709
1992
Hill, R.I.Hill, R.I., Campbell, I.H., Davies, G.F., Griffiths, R.W.Mantle plumes, continental magmatism and tectonicsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.326MantleTectonics, Plumes
DS1993-0671
1993
Hill, R.I.Hill, R.I.Mantle plumes and continental tectonicsLithos, Vol. 30 mo. 3-4, September pp. 193-206MantleTectonics -Plumes, Hot spots
DS1993-0672
1993
Hill, R.I.Hill, R.I.Mantle plumes and continental tectonicsLithos, Vol. 30, No. 3-4, September pp. 193-206.MantlePlumes, Tectonics
DS1994-0070
1994
Hill, R.L.Ashley, P.M., Cook, N.D.J., Hill, R.L., Kent, A.J.R.Shoshonitic lamprophyre dykes and their relation to mesothermal Au-Sb vein sat Hillgrove, New South Wales.Lithos, Vol. 32, No. 3-4, July pp. 249-272.AustraliaShoshonites, Gold, silver
DS1940-0220
1949
Hill, R.S.Thoenen, J.R., Hill, R.S., Howe, E.G., Runke, S.M.Investigation of the Prairie Creek Diamond Area, Pike County,arkansaw.United States Bureau of Mines Report INV., No. 4549, 24P.United States, Gulf Coast, Arkansas, PennsylvaniaEvaluation
DS1860-0593
1888
Hill, R.T.Hill, R.T.The Meozoic Geology of Southwestern ArkansasArkansas Geological Survey Report FOR 1888, Vol. 2, PP. 56-61.United States, ArkansasRegional Geology
DS200712-0421
2007
Hill, S.Hatton, C., Hill, S., Apter, D., Evans, S., Hatch, D., Hauser, B.Measuring the width of the diamond window by logging the lithosphere with garnet compositions.Diamonds in Kimberley Symposium & Trade Show, Bristow and De Wit held August 23-24, Kimberley, South Africa, GSSA Diamond Workshop CD slides 27Africa, South AfricaGroup I,II kimberlites- plumes, peridotites, eclogites
DS1990-0699
1990
Hill, S.J.Hill, S.J.Workstations: problems they solve and problems they createLeading Edge of Exploration (Geophysics News letter), Vol. 9, No. 3, March pp. 24-28GlobalComputers, Geophysics -workstations
DS1990-0840
1990
Hill, S.J.Kirkley, M.B., Gurney, J.J., Otter, M.L., Hill, S.J.Modeling subducted crustal carbon sources for eclogitic diamondsEos, Vol. 71, No. 17, April 24, p. 644 Abstract onlySouth Africa, Colorado, WyomingEclogitic diamond genesis, Geochronology -carbon
DS1991-0879
1991
Hill, S.J.Kirkley, M.B., Gurney, J.J., Otter, M.L., Hill, S.J., Daniels, L.R.The application of Carbon isotope measurements to the identification of the sources of C in diamonds: a reviewApplied Geochemistry, Vol. 6, No. 5, pp. 477-494GlobalGeochronology, Carbon, diamonds
DS1995-0965
1995
Hill, S.J.Kirkley, M.B., Gurney, J.J., Hill, S.J.Diamond mining on kimberlite dikes of South AfricaProceedings of the Sixth International Kimberlite Conference Abstracts, pp. 277-278.South AfricaGroup II kimberlites -dikes, Deposit - Bellsbank, Bobbejaan, Ardo, Roberts Victor
DS201412-0357
2014
Hillbom, E.Hillbom, E.Cattle, diamonds and institutions: main drivers of Botswana's economic development, 1850- to presentJournal of International Development, Vol. 26, 3, pp. 155-176.Africa, BotswanaEconomics
DS201905-1042
2018
Hillbom, E.Hillbom, E., Bolt, J.Botswana - a modern economic history: an African diamond in the rough.Palgrave Macmillan, 235p. ISBN 9783319731438Africa, BotswanaHistory

Abstract: Together with Mauritius, Botswana is often categorized as one of two growth miracles in sub-Saharan Africa. Due to its spectacular long-run economic performance and impressive social development, it has been termed both an economic success story and a developmental state. While there is uniqueness in the Botswana experience, several aspects of the country’s opportunities and challenges are of a more general nature. Throughout its history, Botswana has been both blessed and hindered by its natural resource abundance and dependency, which have influenced growth periods, opportunities for economic diversification, strategies for sustainable economic and social development, and the distribution of incomes and opportunities. Through a political economy framework, Hillbom and Bolt provide an updated understanding of an African success story, covering the period from the mid-19th century, when the Tswana groups settled, to the present day. Understanding the interaction over time between geography and factor endowments on the one hand, and the development of economic and political institutions on the other, offers principle lessons from Botswana’s experience to other natural resource rich developing countries.
DS1950-0136
1953
Hiller, V.M.Hiller, V.M.The Story of Cecil Rhodes. Set Out in a Series of Historical Pictures and Objects to Commemorate the Centenary of His Birth. L853-l953.Bulawayo, 192P.South AfricaBiography, Kimberley
DS1994-0773
1994
Hillgren, V.J.Hillgren, V.J., Drake, M.J., Rubie, D.C.high pressure and high temperature experiments on core mantle segregation in the accreting earth.Science, Vol. 264, No. 5164, June 3, pp. 1442-1444.MantleBlank
DS1996-0631
1996
Hillgren, V.J.Hillgren, V.J., Drake, M.J., Rubie, D.C.high pressure and high temperature metal silicate partitioning of siderophile elements: composition..Geochimica et Cosmochimica Acta, Vol. 60, No. 12, June pp. 2257-2263MantleSilicate liquid composition, Siderophile Metal partioning
DS1998-0619
1998
Hillgren, V.J.Hillgren, V.J., Boehler, R.high pressure reactions between light metals and silicates; Implications for the light element ....Mineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 624-5.MantleCore-mantle boundary, light rare earth element (LREE).
DS200712-0437
2007
Hillgren, V.J.Hillgren, V.J., Schwager, B., Boehler, R.Potassium as a heat source in the core? Metal-silicate partitioning of K and other alkali metals.Plates, Plumes, and Paradigms, 1p. abstract p. A406.MantleGeochemistry
DS1995-0166
1995
Hillhouse, J.W.Bogue, S.W., Gromme, S., Hillhouse, J.W.Paleomagnetism, magnetic anisotropy and mid-Cretaceous paleolatitude of Duke Island Alaska ultramafic complexTectonics, Vol. 14, No. 5, October pp. 1133-1152AlaskaPaleomagnetism, Duke Island Complex
DS1860-0845
1894
Hillier, A.P.Hillier, A.P.In the VeldtLondon: Longmans Green And Co., 112P.Africa, South AfricaTravelogue
DS1900-0025
1900
Hillier, A.P.Hillier, A.P.Diamond Fields. South African SketchesLondon:, PP. 17-21.Africa, South AfricaHistory
DS1990-0946
1990
Hillier, J.A.Lofty, G.J., Hillier, J.A., Burton, E.M., Cooke, S.A., Glaves, H.M.Diamond. Production, Exports, importsBritish Geological Survey World Mineral Statistics, 1984-1988, 6pGlobalDiamond production, Economics
DS201312-0860
2013
Hillier, M.Snyder, D.B., Hillier, M., Kjarsgaard, B.A.3-D structural model of the Slave craton mantle lithosphere, Northwest Territories.Geoscience Forum 40 NWT, abstract only p. 47.Canada, Northwest TerritoriesTectonics
DS201412-0858
2014
Hillier, M.J.Snyder, D.B., Hillier, M.J., Kjarsgaard, B.A., de Kemp, E.A., Craven, J.A.Lithospheric architecture of the Slave Craton, northwest Canada, as determined from an inter disciplinary 3-D model.Geochemistry, Geophysics, Geosystems: G3, Vol. 15, DOI: 10:1002/2013 GC005168Canada, Northwest TerritoriesTectonics
DS201601-0045
2015
Hillier, M.J.Snyder, D.B., Craven, J.A., Pilkington, M., Hillier, M.J.The three dimensional construction of the Rae craton, central Canada.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 10, pp. 3555-3574.Canada, Saskatchewan, AlbertaRae Craton

Abstract: Reconstruction of the 3-dimensional tectonic assembly of early continents, first as Archean cratons and then Proterozoic shields, remains poorly understood. In this paper, all readily available geophysical and geochemical data are assembled in a 3-D model with the most accurate bedrock geology in order to understand better the geometry of major structures within the Rae craton of central Canada. Analysis of geophysical observations of gravity and seismic wave speed variations revealed several lithospheric-scale discontinuities in physical properties. Where these discontinuities project upward to correlate with mapped upper crustal geological structures, the discontinuities can be interpreted as shear zones. Radiometric dating of xenoliths provides estimates of rock types and ages at depth beneath sparse kimberlite occurrences. These ages can also be correlated to surface rocks. The 3.6-2.6 Ga Rae craton comprises at least three smaller continental terranes, which "cratonized" during a granitic bloom. Cratonization probably represents final differentiation of early crust into a relatively homogeneous, uniformly thin (35-42 km), tonalite-trondhjemite-granodiorite crust with pyroxenite layers near the Moho. The peak thermotectonic event at 1.86-1.7 Ga was associated with the Hudsonian orogeny that assembled several cratons and lesser continental blocks into the Canadian Shield using a number of southeast-dipping megathrusts. This orogeny metasomatized, mineralized, and recrystallized mantle and lower crustal rocks, apparently making them more conductive by introducing or concentrating sulfides or graphite. Little evidence exists of thin slabs similar to modern oceanic lithosphere in this Precambrian construction history whereas underthrusting and wedging of continental lithosphere is inferred from multiple dipping discontinuities.
DS1998-0210
1998
Hillier, W.Carlson, J.A., Kirkley, M.B., Thomas, E.M., Hillier, W.Recent major kimberlite discoveries in Canada7th International Kimberlite Conference Abstract, pp. 127-131.Northwest Territories, AlbertaSlave Craton, Buffalo Hills
DS1998-0216
1998
Hillier, W.D.Carlson, S.M., Hillier, W.D., Hood, C.T., Pryde, R.P.The Buffalo Hills kimberlite province, north central Alberta, Canada7th International Kimberlite Conference Abstract, pp. 138-140.AlbertaKimberlites, Petrography
DS201212-0474
2012
Hilliger, K.Miller, R.D., Bradford, J.H., Hilliger, K.Advances in near surface seismology and ground penetrating radar. ( not specific to diamonds)AGU, 487p. Approx. $ 150.00TechnologyBook - radar
DS201412-0292
2014
Hillis, R.Giles, D., Hillis, R., Clverely, J.Deep exploration technologies provide the pathway to deep discovery.SEG Newsletter, No. 97, April pp. 1, 23-27.TechnologyNot specific to diamonds
DS2000-0412
2000
Hillis, R.R.Hillis, R.R., Reynolds, D.D.The Australian stress mapJournal of Geological Society of London, Vol. 157, No. 5, Sept.pp.915-22.AustraliaMap - structure, Tectonics
DS2002-1331
2002
Hillis, R.R.Reynolds, S.D., Coblentz, D.D., Hillis, R.R.Tectonic forces controlling the regional intraplate stress field in continental Australia: results from new finite element modeling.Journal of Geophysical Research, Vol. 107, 7, ETG 1, DOI 10.1029/2001BJ000408.AustraliaGeophysics - seismics, tectonic - model
DS2003-0584
2003
Hillis, R.R.Hillis, R.R., Muller, R.D.Evolution and dynamics of the Australian plate: introductionHillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological, No. 372, pp. 1-6.AustraliaBlank
DS200412-0829
2003
Hillis, R.R.Hillis, R.R., Muller, R.D.Evolution and dynamics of the Australian plate.Geological Society of Australia and Geological Society of America, SP 22, 438p. approx. $ 120.TechnologyBook - geodynamics, mantle seismics, regional geology
DS200412-0830
2003
Hillis, R.R.Hillis, R.R., Muller, R.D.Evolution and dynamics of the Australian plate: introduction.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 1-6.AustraliaGeodynamics
DS200412-0831
2004
Hillis, R.R.Hillis, R.R., Reynolds, S.D.In situ stress field of Australia.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 41-48.AustraliaGeophysics - seismics
DS200412-1660
2004
Hillis, R.R.Reynolds, S.D., Coblentz, D.D., Hillis, R.R.Influence of plate boundary forces on the regional intraplate stress field of continental Australia.Hillis, R.R., Muller, R.D. Evolution and dynamics of the Australian Plate, Geological Society America Memoir, No. 372, pp. 49-58.AustraliaGeophysics - seismics
DS2003-0585
2003
Hillis. R.R.Hillis. R.R., Muller, R.D.Evolution and dynamics of the Australian plateGeological Society of Australia and Geological Society of America, SP 22, 438p. approx. $ 120.GlobalBook - geodynamics, mantle seismics, regional geology
DS1988-0306
1988
Hills, D.V.Hills, D.V.The petrography, mineral chemistry, and geochemistry of eclogites from the Koidu kimberlite complex, Sierra LeoneMsc. Thesis University Of Massachusetts, 209pSierra LeoneEclogites, Geochemistry
DS1989-0641
1989
Hills, D.V.Hills, D.V., Haggerty, S.E.Petrochemistry of eclogites from the Koidu kimberliteComplex, SierraLeoneContributions to Mineralogy and Petrology, Vol. 103, No. 4, pp. 397-422Sierra LeonePetrochemistry, Eclogites
DS1989-1503
1989
Hills, D.V.Toft, P.B., Hills, D.V., Haggerty, S.E.Crustal evolution and the granulite to eclogite transition in xenoliths from kimberlites in the West African cratonTectonophysics, Vol. 161, No. 3/4, pp. 213-231GlobalEclogite
DS1990-0700
1990
Hills, D.V.Hills, D.V., Haggerty, S.E.Eclogites from Koidu kimberlite Complex, Sierra Leone,lithospheric and ultra deep asthenospheric originsEos, Vol. 71, No. 17, April 24, p. 523 Poster Abstract onlySierra LeoneKoidu, Eclogites
DS1960-0962
1968
Hills, F.A.Hills, F.A., Gast, P.W., Houston, R.S., Swainbank, I.G.Precambrian Geochronology of the Medicine Bow Mountains, Southeastern Wyoming #1Geological Society of America (GSA) Bulletin., Vol. 79, PP. 1757-1783.United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1960-0963
1968
Hills, F.A.Hills, F.A., Gast, P.W., Houston, R.S., Swainbank, I.G.Precambrian Geochronology of the Medicine Bow Mountains, Southeastern Wyoming #2Wyoming Geological Survey Memoir., No. 1.United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1970-0929
1974
Hills, F.A.Hills, F.A., Armstrong, R.L.Geochronology of Precambrian Rocks in the Laramie Range And implications for the Tectonic Framework of Precambrian Southern Wyoming.Precambrian Research, Vol. 1, PP. 213-225.United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1975-0104
1975
Hills, F.A.Hills, F.A., Houston, R.S., Gast, P.W.Chronology of Some Precambrian Igneous and Metamorphic Events of the Medicine Bow Mountains, Wyoming.Geological Society of America (GSA) SPECIAL PAPER., No. 82, P. 92, (abstract.).United States, Wyoming, Rocky Mountains, Medicine Bow MountainsBlank
DS1975-0761
1978
Hills, F.A.Hills, F.A., Houston, R.S.Early Proterozoic Tectonics of Southern Wyoming and Northern Colorado and the Tectonic Setting of Radioactive Precambrian Conglomerates.Wyoming Public Inf. Circular, No. 7, P. 19.United States, Wyoming, Colorado, Rocky Mountains, State LineKimberlite, Tectonics, State Line Rocky Mountains
DS1975-1073
1979
Hills, F.A.Hills, F.A., Houston, R.S.Early Proterozic Tectonics of the Central Rocky Mountains, North America.University WYOMING Contributions to Geology, Vol. 17, No. 2, PP. 89-109.United States, Wyoming, State Line, Rocky MountainsBlank
DS1991-0715
1991
Hills, F.A.Hills, F.A., Scott, R.W., Armbrustmacher, T.J., Berendsen, P.Map showing distribution of alkaline igneous rocks and associated carbonatites and peridotites in the northern mid-continent, United States (US)United States Geological Survey (USGS) Map, No. MF-1835-F, 15p. 1 map 1: 1, 000, 000 $ 1.50MidcontinentCarbonatite, Map -Alkaline intrusives
DS1991-0716
1991
Hills, F.A.Hills, F.A., Scott, R.W., Armbrustmacher, T.J., Berendsen, P.Map showing the distribution of alkaline igneous rocks and associated carbonatites and peridotites in the northern mid-continent, United States (US)United States Geological Survey (USGS) Map, No. MF 1835-F, 1: 1, 000, 000MidcontinentMap, Carbonatite
DS202105-0766
2021
Hills, S.Hills, S.Fluorescence microscopy: the revolution revolving.Carnegiescience.edu, June 8, 2pm. ESTGlobalfluorescence
DS201910-2269
2018
Hilmi Hazim, S.Kavanagh, J.L., Burns, A.J., Hilmi Hazim, S., Wood, E.P., Martin, S.A., Hignett, S., Dennis, D.J.C.Challenging dyke ascent models using novel laboratory experiments: implications for reinterpreting evidence of magma accent and volcanism.Journal of Volcanology and Geothermal Research, Vol. 354, pp. 87-101.Mantlemagmatism

Abstract: Volcanic eruptions are fed by plumbing systems that transport magma from its source to the surface, mostly fed by dykes. Here we present laboratory experiments that model dyke ascent to eruption using a tank filled with a crust analogue (gelatine, which is transparent and elastic) that is injected from below by a magma analogue (dyed water). This novel experimental setup allows, for the first time, the simultaneous measurement of fluid flow, sub-surface and surface deformation during dyke ascent. During injection, a penny-shaped fluid-filled crack is formed, intrudes, and traverses the gelatine slab vertically to then erupt at the surface. Polarised light shows the internal stress evolution as the dyke ascends, and an overhead laser scanner measures the surface elevation change in the lead-up to dyke eruption. Fluorescent passive-tracer particles that are illuminated by a laser sheet are monitored, and the intruding fluid's flow dynamics and gelatine's sub-surface strain evolution is measured using particle image velocimetry and digital image correlation, respectively. We identify 4 previously undescribed stages of dyke ascent. Stage 1, early dyke growth: the initial dyke grows from the source, and two fluid jets circulate as the penny-shaped crack is formed. Stage 2, pseudo-steady dyke growth: characterised by the development of a rapidly uprising, central, single pseudo-steady fluid jet, as the dyke grows equally in length and width, and the fluid down-wells at the dyke margin. Sub-surface host strain is localised at the head region and the tail of the dyke is largely static. Stage 3, pre-eruption unsteady dyke growth: an instability in the fluid flow appears as the central fluid jet meanders, the dyke tip accelerates towards the surface and the tail thins. Surface deformation is only detected in the immediate lead-up to eruption and is characterised by an overall topographic increase, with axis-symmetric topographic highs developed above the dyke tip. Stage 4 is the onset of eruption, when fluid flow is projected outwards and focused towards the erupting fissure as the dyke closes. A simultaneous and abrupt decrease in sub-surface strain occurs as the fluid pressure is released. Our results provide a comprehensive physical framework upon which to interpret evidence of dyke ascent in nature, and suggest dyke ascent models need to be re-evaluated to account for coupled intrusive and extrusive processes and improve the recognition of monitoring signals that lead to volcanic eruptions in nature.
DS201908-1793
2019
Hiloidari, S.Mohanty, N., Singh, S.P., Satyanarayanan, M., Jayananda, M., Korakoppa, M.M., Hiloidari, S.Chromianspinel compositions from Madawara ultramafics, Bundelkhand craton: implications on petrogenesis and tectonic evolution of the southern part of the Bundelkhand craton, central India.Geological Journal, Vol. 54, 4, pp. 2099-2123.Indiacraton

Abstract: Madawara ultramafic complex (MUC) in the southern part of Bundelkhand Craton, Central India comprises peridotite, olivine pyroxenite, pyroxenite, gabbro, and diorite. Coarse?grained olivine, clinopyroxene (Cpx), amphibole (Amp), Al?chromite, Fe?chromite, and magnetite with rare orthopyroxene (Opx) are common minerals in peridotite. Chromites are usually coarse?grained euhedral found as disseminated crystals in the olivine matrix showing both homogeneous and zoned texture. Al?chromite, primarily characterizes Cr?spinels and its subsequent fluid activity and alteration can result in the formation of Fe?chromite, chrome magnetite, and magnetite. Mineral chemistry data suggest that Al?chromite is characterized by moderately high Cr2O3 (38.16-51.52 wt.%) and Fe2O3 (3.22-14.51 wt.%) and low Al2O3 (10.63-21.87 wt.%), MgO (1.71-4.92 wt.%), and TiO2 (0.22-0.67 wt.%), whereas the homogeneous Fe?chromite type is characterized by high Fe2O3 (25.54-47.60 wt.%), moderately low Cr2O3 (19.56-37.90 wt.%), and very low Al2O3 (0.06-1.53 wt.%). Subsequent alteration of Al?chromite and Fe?chromite leads to formation of Cr?magnetite and magnetite. The Cr# of Al?chromite varies from 55.12 to 76.48 and ?Fe3+# from 8 to 19, whereas the ferrian chromite has high Cr# varying from 94.27 to 99.53 while its ?Fe3+# varies from 38 to 70. As a whole, the primary Al?chromite shows low Al2O3, TiO2 contents, and high Fe#, Cr# values. Olivines have forsterite ranging from 75.96% to 77.59%. The bulk?rock geochemistry shows continental arc geochemical affinities indicated by the high concentration of large?ion lithophile elements and U, Th relative to the low concentration of high?field strength elements. These petrological and mineralogical as well as primary Al?chromite compositions plotted in different discrimination diagrams suggest an arc environment that is similar to Alaskan?type intrusion.
DS2000-0413
2000
Hilson, G.Hilson, G.Barriers to implementing cleaner technologies and cleaner production (CP) practices in mining industryMinerals Eng., Vol. 13, No. 7, pp. 699-717.United States, Canada, Ontario, AmazonasEnvironment, Mining - practices, pollution
DS2002-0717
2002
Hilson, G.Hilson, G.Small scale mining and its socio economic impact in developing countriesNatural Resources Forum, Vol.26,1,pp. 3-14.BrazilEconomics - legal, social
DS200512-0432
2005
Hilson, G.Hilson, G.Strengthening artisanal mining research and policy through baseline census activities.Natural Resources Forum, Vol. 29, 2, pp. 144-153.Mining - alluvials
DS200512-0433
2004
Hilson, G.Hilson, G., Haselip, J.The environmental and socioeconomic performance of multinational mining companies in the developing world economy.Minerals & Energy - Raw Materials Report, Vol. 19, 3, Sept. pp. 23-47.GlobalEnvironmental
DS201603-0398
2016
Hilson, G.Maconachie, R., Hilson, G.Re-thinking the child labour "problem" in rural sub-Saharan Africa: the case of Sierra Leone's half shovels.World Development, Vol. 78, pp. 136-147.Africa, Sierra LeoneHistory

Abstract: This article contributes to evolving debates on Sierra Leone’s post-war “crisis of youth” by providing an extended analysis of the role that young boys and girls assume in negotiating household poverty and enhancing their livelihood opportunities in small-scale mining communities. Child miners – or “half shovels” as they are locally known – are both directly and indirectly involved in small-scale gold extraction in Kono District, Sierra Leone’s main diamond-producing area. But the implications of their involvement are often far more nuanced and complex than international children’s rights advocates understand them to be. Drawing upon recent fieldwork carried out in and around the Kono mining village of Bandafayie, the article argues that children’s participation in the rural economy not only generates much-needed household income, but in many cases is the only way in which they can earn the monies needed to attend school. A blind and uncritical acceptance of international codes and agreements on child labor could have an adverse impact on children and, by extension, poor communities in rural Sierra Leone. Western notions of “progress” and development, as encapsulated in the post-conflict reconstruction programing of international NGOs and donor organizations, often do not match up with the complex realities or competing visions of local people.
DS201810-2350
2018
Hilson, G.Maconachie, R., Hilson, G.The war whose bullets you don't see: diamond digging, resilience and ebola in Sierra Leone.Journal of Rural Studies, Vol. 61, 1, pp. 110-122.Africa, Sierra Leonealluvials

Abstract: This paper reflects critically on the transformational impacts the recent Ebola epidemic has had in diamond-rich areas of rural Sierra Leone. It focuses specifically on the country's ‘diggers’, a sizable group of labourers who occupy the bottom of the country's artisanal diamond mine production pyramid. Based upon research conducted in the diamond-producing localities of Kenema and Kono, the paper argues how, in sharp contrast to the gloomy picture painted in the literature about their existences and struggles, diggers exhibited considerable resilience during the Ebola crisis. Their diversified livelihood portfolios proved to be effective survival strategies and buffers against the shocks and stresses brought about by lengthy periods of quarantine, and during times when mobility was restricted by the government in a bid to prevent the spreading of the disease. Drawing inspiration from the resilience literature, the paper captures the essence of these survival strategies, which should be viewed as latest reshuffling and expansion of diggers' rural livelihood portfolios. Policymakers and donors have yet to embrace fully these changes in a country where the Ebola recovery period promises to be lengthy and at a time when fresh, locally-informed rural development solutions are in short supply.
DS202011-2042
2020
Hilson, G.Hilson, G.The African mining vision: a manifesto for more inclusive extractive industry-led developments.Canadian Journal of Development Studies, Vol. 41, 3, pp. 417-431. pdfAfricalegal

Abstract: This paper introduces a special section of the Canadian Journal of Development Studies, "The Africa Mining Vision: A Manifesto for More Inclusive Extractive Industry-Led Development?" Conceived by African ministers "in charge of mineral resources" with inputs and guidance from African Union Heads of State, the Africa Mining Vision (AMV) was officially launched in February 2009. The papers presented in this special section reflect critically on progress that has since been made with operationalising the AMV at the country level across Africa; the general shortcomings of the manifesto; and the challenges that must be overcome if the continent is to derive greater economic benefit from its abundant mineral wealth.
DS2002-0718
2002
Hilson, G.M.Hilson, G.M.Delivering aid to grass roots industries: a critical evaluation of small scale mining support services.Minerals and Energy, Vol. 17,1,March pp.11-18.GlobalEconomics - legal, policy, Socio-environmental
DS200512-0220
2005
Hilton, D.R.Day, J.M.D., Hilton, D.R., Pearson, D.G., MacPherson, C.G., Kjarsgaard, B.A., Janney, P.E.Absence of a high time integrated 3He (U-Th) source in the mantle beneath continents.Geology, Vol. 33, 9, Sept. pp. 733-736.Mantle, Canada, Africa, South Africa, UgandaGeochronology - helium isotopes
DS200512-0671
2005
Hilton, D.R.MacPherson, C.G., Hilton, D.R., Day, J.M., Lowry, D., Grenvold, K.High 3He 4He depleted mantle and low 180 recycled oceanic lithosphere in the source of central Iceland magmatism.Physics and Planetary Science Letters, Vol. 233, 3-4, pp. 411-427.MantleGeochemistry
DS200512-0672
2005
Hilton, D.R.MacPherson, C.G., Hilton, D.R., Day, J.M.D., Lowry, D., Gronvold, K.High He3 He4 depleted mantle and low delta18O recycled oceanic lithosphere in the source of central Iceland magmatism.Earth and Planetary Science Letters, Vol. 233, 3-4, May 15, pp. 411-427.Europe, IcelandMagmatism, geochronology, recycling
DS200612-1088
2005
Hilton, D.R.Pik, R., Marty, B., Hilton, D.R.How many mantle plumes in Africa? The geochemical point of view.Chemical Geology, Vol. 226, 3-4, pp. 100-114.AfricaAfrican plate, Hoggar, Tibesti, Darfur, Ethiopia, Kenya
DS200812-0470
2007
Hilton, D.R.Hilton, D.R.The leaking mantle.Science, Vol. 318 No. 5855 Nov. 30, p. 1389.MantleGeochemistry
DS201212-0641
2012
Hilton, D.R.Shaw, A.M., Hauri, E.H., Behn, M.D., Hilton, D.R., MacPherson, C.G., Sinton, J.M.Long term preservation of slab signatures in the mantle interred from hydrogen isotopes.Nature Geoscience, Vol. 5, March pp, 224-228.MantleTomography - seismics
DS201312-0200
2013
Hilton, D.R.De Moor, M., Fischer, T.P., King, P.L., Botcharnikov, R.E., Hervig, R.L., Hilton, D.R., Barry, P.H., Mangasini, F., Ramirez, C.Volatile rich silicate melts from Oldoinyo Lengai volcano (Tanzania): implications for carbonatite genesis and eruptive behavior.Earth and Planetary Science Letters, Vol. 361, pp. 379-390.Africa, TanzaniaDeposit - Oldoinyo Lengai
DS201312-0356
2013
Hilton, D.R.Hallis, L.J., Huss, G.R., Taylor, D.R., Nagashima, K., Halldorsson, S.A., Hilton, D.R.The D/H ratio of the deep mantle.Goldschmidt 2013, AbstractMantleDeuterium/Hydrogen
DS201504-0183
2015
Hilton, D.R.Barry, P.H., Hilton, D.R., Day, J.M.D., Pernet-Fisher, J.F., Howarth, G.H., Magna, T., Agashev, A.M., Pokhilenko, N.P., Opkhilenko, L.N., Taylor, L.A.Helium isotope evidence for modification of the cratonic lithosphere during the Permo-Triassic Siberian flood basalt event.Lithos, Vol. 216-217, pp. 73-80.Russia, SiberiaDeposit - Udachnaya, Obnazhennaya

Abstract: Major flood basalt emplacement events can dramatically alter the composition of the sub-continental lithospheric mantle (SCLM). The Siberian craton experienced one of the largest flood basalt events preserved in the geologic record — eruption of the Permo-Triassic Siberian flood basalts (SFB) at ~250 Myr in response to upwelling of a deep-rooted mantle plume beneath the Siberian SCLM. Here, we present helium isotope (3 He/ 4 He) and concentra-tion data for petrologically-distinct suites of peridotitic xenoliths recovered from two temporally-separated kim-berlites: the 360 Ma Udachnaya and 160 Ma Obnazhennaya pipes, which erupted through the Siberian SCLM and bracket the eruption of the SFB. Measured 3 He/ 4 He ratios span a range from 0.1 to 9.8 R A (where R A = air 3 He/ 4 He) and fall into two distinct groups: 1) predominantly radiogenic pre-plume Udachnaya samples (mean clinopyroxene 3 He/ 4 He = 0.41 ± 0.30 R A (1?); n = 7 excluding 1 outlier), and 2) 'mantle-like' post plume Obnazhennaya samples (mean clinopyroxene 3 He/ 4 He = 4.20 ± 0.90 R A (1?); n = 5 excluding 1 outlier). Olivine separates from both kimberlite pipes tend to have higher 3 He/ 4 He than clinopyroxenes (or garnet). Helium con-tents in Udachnaya samples ([He] = 0.13–1.35 ?cm 3 STP/g; n = 6) overlap with those of Obnazhennaya ([He] = 0.05–1.58 ?cm 3 STP/g; n = 10), but extend to significantly higher values in some instances ([He] = 49– 349 ?cm 3 STP/g; n = 4). Uranium and thorium contents are also reported for the crushed material from which He was extracted in order to evaluate the potential for He migration from the mineral matrix to fluid inclusions. The wide range in He content, together with consistently radiogenic He-isotope values in Udachnaya peridotites suggests that crustal-derived fluids have incongruently metasomatized segments of the Siberian SCLM, whereas high 3 He/ 4 He values in Obnazhennaya peridotites show that this section of the SCLM has been overprinted by Permo-Triassic (plume-derived) basaltic fluids. Indeed, the stark contrast between pre-and post-plume 3 He/ 4 He ra-tios in peridotite xenoliths highlights the potentially powerful utility of He-isotopes for differentiating between various types of metasomatism (i.e., crustal versus basaltic fluids).
DS1993-0258
1993
Hilverda, K.J.Clark, J.A., Hendriks, M., Timmermans, T.J., Struck, C., Hilverda, K.J.Glacial isostatic deformation of the Great Lakes regionGeological Society of America Bulletin, Vol. 106, No. 1, January pp. 19-31.OntarioGeomorphology, Sea level changes, isostasy
DS2002-1302
2002
Himabindu, D.Ramadass, G., Rao, I.B.R., Himabindu, D., SrinivasuluPseudo surface velocities (densities) and pseudo depth densities along profiles Dharwar Craton, India.Current Science, Vol.82,No.2, pp. 197-201.IndiaGeophysics - seismics, Craton - Dharwar
DS2003-1126
2003
Himabindu, D.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransectJournal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200412-1615
2003
Himabindu, D.Ramadass, G., Rao, I.B.R., Srinivasulu, N., Himabindu, D.Density studies in the Dharwar Craton along the Jadcharla Goa subtransect.Journal Geological Society of India, Vol. 61, 4, pp. 439-448.IndiaGeophysics - seismics
DS200512-0888
2005
Himabindu, D.Ramadass, G., Rao, I.B.R., Himabindu, D.Regional appraisal from gravity investigations in the Dharwar Craton: Jadcharla - Goa transect.Journal of the Geological Society of India, Vol. 65, 1, pp. 61-69.IndiaGeophysics - gravity not specific to diamonds
DS200912-0792
2009
Himabindu, D.Veeraiah, B., Ramadass, G., Himabindu, D.A subsurface criterion for predictive exploration of kimberlites from bouguer gravity in the eastern Dharwar craton, India.Journal of the Geological Society of India, Vol. 74, July pp. 69-77.IndiaMaddur-Narayanpet kimberlite, geophysics
DS201112-1084
2009
Himabindu, D.Veeraiah, B., Ramadass, G., Himabindu, D.A subsurface criterion for predictive exploration of kimberlites from Bouguer Gravity in the eastern Dharwa craton, India.Journal of the Geological Society of India, Vol. 74, pp. 69-77.IndiaNarayanpet-Irladinne area
DS2002-1301
2002
Himanbindu, D.Ramadass, G., Ramaprasada Rao, I.B., Himanbindu, D., Srinivasulu, N.Psuedo surface velocities ( densities) and pseudo depth densities ( velocities) along selected profiles in the Dharwar Craton, India.Current Science, Vol. 82,No. 2, Jan. 25, pp. 197-201.IndiaGeophysics - seismics
DS1986-0327
1986
Himmelberg, G.R.Haensel, J.M.Jr., Himmelberg, G.R., Ford, A.B.Plagioclase compositional variations in anorthosites of the lower part Of the Dufek intrusionAntarctic Journal of the United States, Vol. 21, No. 5, pp. 61-63AntarcticaDufek
DS200612-1124
2006
Himnindu, D.Ramadass, G., Ramaprasada Rao, I.B., Himnindu, D.Crustal configuration of the Dhawar Craton, India: based on joint modelling of regional gravity and magnetic data.Journal of Asian Earth Sciences, Vol. 26, 5, pp. 437-448.Asia, IndiaGeophysics - gravity, magnetics
DS200912-0299
2009
Hin, R.C.Hin, R.C., Morel, M.L.A., Nebel, O., Mason, P.R.D., Van Westeren, W., Davies, G.R.Formation and temporal evolution of the Kalahari sub-cratonic lithospheric mantle: constraints from Venetia xenoliths, South Africa.Lithos, In press - available 30p.Africa, South AfricaDeposit - Venetia
DS200712-0769
2006
Hinchey, A.M.Nadeau, L., Ryan, J.J., Hinchey, A.M., James, Sandeman, Tremblay, Schetselaar, Berman, DavisOutlook on the geology of the Boothia MaIn land area, Kitikmeot region, Nunavut.34th Yellowknife Geoscience Forum, p. 39-40. abstractCanada, NunavutGeology - brief overview
DS1989-1073
1989
Hinchey, E.J.Mullins, H.T., Hinchey, E.J.Erosion and infill of New York Finger Lakes:implications for Laurentideice sheet deglaciationGeology, Vol. 17, No. 7, July pp. 622-625GlobalGeomorphology, Finger Lakes
DS201212-0233
2012
Hincks, T.K.Gernon, T., Brown, R.J., Tait, M.A., Hincks, T.K.The origin of pellatal lapilli in explosive kimberlite eruptions.Nature Communcations, May 7p.Africa, South Africa, LesothoDeposit - Venetia, Letseng-la-Terae
DS201604-0608
2016
Hincks, T.K.Gernon, T.M., Hincks, T.K., Tyrell, T., Rohling, E.J., Palmer, M.R.Snowball Earth ocean chemistry driven by extensive ridge volcanism during Rodinia breakup.Nature Geoscience, Vol. 9, 3, pp. 242-248.Gondwana, RodiniaAlkalic

Abstract: During Neoproterozoic Snowball Earth glaciations, the oceans gained massive amounts of alkalinity, culminating in the deposition of massive cap carbonates on deglaciation. Changes in terrestrial runoff associated with both breakup of the Rodinia supercontinent and deglaciation can explain some, but not all of the requisite changes in ocean chemistry. Submarine volcanism along shallow ridges formed during supercontinent breakup results in the formation of large volumes of glassy hyaloclastite, which readily alters to palagonite. Here we estimate fluxes of calcium, magnesium, phosphorus, silica and bicarbonate associated with these shallow-ridge processes, and argue that extensive submarine volcanism during the breakup of Rodinia made an important contribution to changes in ocean chemistry during Snowball Earth glaciations. We use Monte Carlo simulations to show that widespread hyaloclastite alteration under near-global sea-ice cover could lead to Ca2+ and Mg2+ supersaturation over the course of the glaciation that is sufficient to explain the volume of cap carbonates deposited. Furthermore, our conservative estimates of phosphorus release are sufficient to explain the observed P:Fe ratios in sedimentary iron formations from this time. This large phosphorus release may have fuelled primary productivity, which in turn would have contributed to atmospheric O2 rises that followed Snowball Earth episodes.
DS1995-0802
1995
Hinde, C.Hinde, C.International hotspots... overview of presentation to the Prospectors and Developers Association of Canada (PDAC)Prospectors and Developers Association of Canada (PDAC) Annual Publishing Exploration and Dev. Highlights, March pp. 35, 37, 38India, China, INdonesia, Ghana, Russia, ZimbabweFinland, Kazakhstan, Tanzania, Exploration activity
DS200612-0578
2006
Hinde, C.Hinde, C.Software solutions for mine planners.Mining Magazine, April 9p.GlobalEconomics, reserves, computer programs
DS200612-0579
2006
Hinde, C.Hinde, C.Orebody and terrain modelling software solutions. Model behaviour ( computers and latest programs).Mining Magazine, April 8p.GlobalEconomics, reserves, resources, computer programs
DS200612-0580
2006
Hinde, C.Hinde, C.The private sector investment arm of the World Bank, IFC will implement a new set of environmental and social standards in April.Mining Magazine, April 2p.GlobalEnvironment - legal
DS200612-0581
2006
Hinde, C.Hinde, C.London eye..... LSE has announced plans to make changes to the regulations governing AIM.Aspermount, Oct. 6, 1p.Europe, United KingdomNews item - AIM
DS200612-0582
2005
Hinde, C.Hinde, C.You've got to mine it. Mines have a finite life and investors need to be aware of how the mining industry works.World Mining Stocks, Nov. p. 79.GlobalNews item - economics
DS200612-0583
2006
Hinde, C.Hinde, C.Spider's den ... comment and brief overview of how effective the web has been in reaching people..... Mining-Journal's new website update.Mining Magazine, March, 1p.Globalwebsite www.mining-journal.com
DS200712-0438
2006
Hinde, C.Hinde, C.A question of balance.... water is a necessity for mining operations... in excess, it is a hindrance and sometimes even a hazard.Mining Magazine, November pp. 44-48.GlobalMining operations - not specific to diamonds
DS200512-1240
2005
Hinde, J.Zhang, C., Manheim, F.T., Hinde, J., Grossman, J.N.Statistical characteristics of a large geochemical database and effect of sample size.Applied Geochemistry, Vol.20, 10, Oct. pp. 1857-1874.TechnologyGeochemistry - not specific to diamonds
DS1993-1155
1993
Hinds, R.C.Odgers, A.T.R., Hinds, R.C., Von Gruenewaldt, G.Interpretation of a seismic reflection survey across the southern BushveldComplexSouth African Journal of Geology, Vol. 96, No. 4, pp. 205-212South AfricaGeophysics -seismics, Deposit -Bushveld
DS1988-0121
1988
Hine, R.Chappell, B.W., White, A.J.R., Hine, R.Granite provinces and basement terranes in the Lachlan fold belt, southeastern AustraliaAustralian Journal of Earth Sciences, Vol. 35, No. 4, December pp. 505-522AustraliaGranites, Terranes
DS1991-0717
1991
Hinkley, T.K.Hinkley, T.K.Distribution of metals between particulate and gaseous forms in a volcanicplumeBulletin. Volcanology, Vol. 53, pp. 395-400HawaiiMetals, Volcanic plumes
DS201812-2883
2018
Hinks, D.Sims, K., Fox, K., Harris, M., Chimuka, L., Reichhardt, F., Muchemwa, E., Gowera, R., Hinks, D., Smith, C.B.Murowa deposit: Discovery of the Murowa kimberlites, Zimbabwe.Society of Economic Geology Geoscience and Exploration of the Argyle, Bunder, Diavik, and Murowa Diamond Deposits, Special Publication no. 20, pp. 359-378.Africa, Zimbabwedeposit - Murowa
DS201212-0234
2012
Hinks, T.K.Gernon, T.M., Brown, R.J., Tait, N., Hinks, T.K.The origin of pellatal lapilli in explosive kimberlite eruptions.10th. International Kimberlite Conference Held Bangalore India Feb. 6-11, Poster abstractTechnologyPetrology
DS1993-0673
1993
Hinman, M.Hinman, M.A LOTUS 1-2-3 diamond drillhole structural manipulation spreadsheet:drillcore structural dat a generationComputers and Geosciences, Vol. 19, No. 3, pp. 343-354GlobalComputer, Program -drillholes
DS2000-0066
2000
Hinnell, A.Bauman, P.D., Kellett, R., Pagulayan, R., Hinnell, A.Borehole geophysics as an aid to kimberlite exploration in the Canadian Prairie region.Proceedings Symposium Application of Geophysics, pp. 563-5.Alberta, Western Canada Sedimentary BasinGeophysics - gamma ray
DS201312-0386
2013
Hinnov, L.A.Hinnov, L.A.Cyclostratigraphy and its revolutionizing applications in the Earth and planetary sciences.Geological Society of America Bulletin, Vol. 125, pp. 1703-1734.TechnologyStratigraphy
DS2002-0719
2002
Hinojasa, J.H.Hinojasa, J.H., Mickus, K.L.Thermoelastic modeling of lithospheric upliftComputers and Geosciences, Vol. 28, No. 2, pp. 155-67.MantleModel - uplift not specific to diamonds
DS1993-0674
1993
Hinojosa, J.H.Hinojosa, J.H., Mickus, K.L.FORELAND BASIN: a FORTRAN program to model the formation of foreland basins resulting from the flexural deflection of the lithosphere caused -loadComputers and Geosciences, Vol. 19, No. 9, pp. 1321-1332BasinsComputer, Program -FORELAND BASIN.
DS202104-0589
2021
Hinrichs, K-U.Lollar, B.S., Heuer, V.B., McDermott, J., Tille, S., Warr, O., Moran, J.J., Telling, J., Hinrichs, K-U.A window into the abiotic carbon cycle - acetate and formate in fracture waters in 2.7 billion year-old host rocks of the Canadian shield. ( Not specific to diamonds just interest)Geochimica et Cosmochimica Acta, Vol. 294. pp. 295-314. pdfCanadacarbon

Abstract: The recent expansion of studies at hydrothermal submarine vents from investigation of abiotic methane formation to include abiotic production of organics such acetate and formate, and rising interest in processes of abiotic organic synthesis on the ocean-world moons of Saturn and Jupiter, have raised interest in potential Earth analogs for investigation of prebiotic/abiotic processes to an unprecedented level. The deep continental subsurface provides an attractive target to identify analog environments where the influence of abiotic carbon cycling may be investigated, particularly in hydrogeological isolated fracture fluids where the products of chemical water-rock reactions have been less overprinted by the biogeochemical signatures of the planet’s surficial water and carbon cycles. Here we report, for the first time, a comprehensive set of concentration measurements and isotopic signatures for acetate and formate, as well as the dissolved inorganic and organic carbon pools, for saline fracture waters naturally flowing 2.4?km below surface in 2.7 billion year-old rocks on the Canadian Shield. These geologically ancient fluids at the Kidd Creek Observatory were the focus of previous investigations of fracture fluid geochemistry, microbiology and noble gas-derived residence times. Here we show the fracture waters of Kidd Creek contain high concentrations of both acetate and formate with concentrations from 1200 to 1900?µmol/L, and 480 to 1000?µmol/L, respectively. Acetate and formate alone account for more than 50-90% of the total DOC - providing a very simple "organic soup". The unusually elevated concentrations and profoundly 13C-enriched nature of the acetate and formate suggest an important role for abiotic organic synthesis in the deep carbon cycle at this hydrogeologically isolated site. A variety of potential abiotic production reactions are discussed, including a radiolytically driven H, S and C deep cycle that could provide a mechanism for sustaining deep subsurface habitability. Scientific discoveries are beginning to reveal that organic-producing reactions that would have prevailed on Earth before the rise of life, and that may persist today on planets and moons such as Enceladus, Europa and Titan, can be accessed in some specialized geologic settings on Earth that provide valuable natural analog environments for the investigation of abiotic organic chemistry outside the laboratory.
DS201412-0435
2014
Hinrichs, R.Juchem, P.L., Hinrichs, R., Traverso, M.Analise multi-technicas para identificar diamante e moissanta em joias. 6 Simposio Brasileiro de Geologia do Diamante, Aug. 3-7, 6p. AbstractTechnologyMoissanite
DS201312-0387
2011
Hinsbergen, D.J.J.Hinsbergen, D.J.J., Buiter, S.J.H., Torsvik, T.H., Gaina, G., Webb, S.J.Formation and evolution of Africa: a synopsis of 3.8 Ga of Earth history.Geological Society of London, Special Publication no. 357, 378p. Approx 120 lbsAfricaTectonics
DS201902-0303
2018
Hinsbergen, D.J.J.Nikogosian, I.K., Bracco Gartner, A.J.J., Bergen, M.J., Mason, P.R.D., Hinsbergen, D.J.J.Mantle sources of recent Anatolian intraplate magmatism: a regional plume or local tectonic origin?Tectonics, Vol. 37, 12, pp. 4535-4566.Asia, Turkeymagmatism

Abstract: We present an extensive study of rehomogenized olivine?hosted melt inclusions, olivine phenocrysts, and chromian spinel inclusions to explore the link between geodynamic conditions and the origin and composition of Pliocene-Quaternary intraplate magmatism in Anatolia at Kula, Ceyhan?Osmaniye, and Karacada?. Exceptional compositional variability of these products reveals early and incomplete mixing of distinct parental melts in each volcanic center, reflecting asthenospheric and lithospheric mantle sources. The studied primitive magmas consist of (1) two variably enriched ocean island basalt (OIB)?type melts in Kula; (2) both OIB?type and plume mid?ocean ridge basalt (P?MORB)?like melts beneath Toprakkale and Üçtepeler (Ceyhan?Osmaniye); and (3) two variably enriched OIB?type melts beneath Karacada?. Estimated conditions of primary melt generation are 23-9 kbar, 75-30 km, and 1415-1215 °C for Kula; 28-19 kbar, 90-65 km, and 1430-1350 °C for Toprakkale; 23-18 kbar, 75-60 km, and 1400-1355 °C for Üçtepeler; and 35-27 kbar, 115-90 km, and 1530-1455 °C for Karacada?, the deepest levels of which correspond to the depth of the lithosphere?asthenosphere boundary in all regions. Although magma ascent was likely facilitated by local deformation structures, recent Anatolian intraplate magmatism seems to be triggered by large?scale mantle flow that also affects the wider Arabian and North African regions. We infer that these volcanics form part of a much wider Arabian?North African intraplate volcanic province, which was able to invade the Anatolian upper plate through slab gaps.
DS2000-0939
2000
Hintermuller, M.Stuwe, K., Hintermuller, M.Topography and isotherms revisited: the influence of laterally migrating drainage studies.Earth and Planetary Science Letters, Vol. 184, No.1, Dec.30, pp.287-303.EuropeGeomorphology - divides, lateral migration, Geochronology - low temperature
DS2001-1301
2001
HintonZhang, H.F., Menzies, M.A., Mattey, Hinton, GurneyPetrology, mineralogy and geochemistry of oxide minerals in polymict xenoliths from Bultfontein...Contributions to Mineralogy and Petrology, Vol. 141, No. 3, June, pp. 367-79.South AfricaGeochronology - low bulk rock oxygen ratios, Deposit - Bultfontein
DS2002-1658
2002
Hinton, J.J.Veiga, M.M., Hinton, J.J.Abandoned artisanal gold mines in the Brazilian Amazon: a legacy of mercury pollutionNatural Resources Forum, Vol.26,1,pp. 15-26.BrazilGold - mining, pollution, environment
DS200412-0476
2004
Hinton, R.Downes, H., Beard, A., Hinton, R.Natural experimental charges: an ion microprobe study of trace element distribution coefficients in glass rich hornblendite andLithos, Vol. 75, 1-2, July, pp. 1-17.Europe, Germany, IsraelMagmatism, alkaline, igneous glasses, basanite. foidite
DS1999-0758
1999
Hinton, R.W.Upton, B.G.J., Hinton, R.W., Valley, J.W.Megacrysts and associated xenoliths: evidence for migration of geochemically enriched melts upper mantleJournal of Petrology, Vol. 40, No. 6, June 1, pp. 935-56.MantleGeochemistry, Xenoliths
DS2001-1175
2001
Hinton, R.W.Upton, B.G., Aspen, P., Hinton, R.W.Pyroxenite and granulite xenoliths from beneath: evidence for lower crust/upper mantle....Contribution Mineralogy Petrology, Vol. 142, No. 2, pp. 178-97.ScotlandXenoliths
DS2001-1176
2001
Hinton, R.W.Upton, B.G.J., Aspen, P., Hinton, R.W.Pyroxenite and granulite xenoliths from beneath the Scottish Northern Highlands Terrane: evidence....Contributions to Mineralogy and Petrology, Vol. 142, No. 2, Nov. pp. 178-97.ScotlandXenoliths, Lower crust upper mantle relationship
DS2002-0363
2002
Hinton, R.W.Dawson, J.B., Hinton, R.W.Trace element content and partioning in carbonatite carbonates and apatite, Phalaborwa South Africa.18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.246.South AfricaCarbonatite - mineralogy
DS2003-0323
2003
Hinton, R.W.Dawson, J.B., Hinton, R.W.Trace element content and partitioning in calcite, dolomite and apatite in carbonatiteMineralogical Magazine, Vol. 67, 5, pp. 921-930.South AfricaGeochemistry - Palabora
DS2003-1399
2003
Hinton, R.W.Upton, B.G.J., Aspen, P., Hinton, R.W.Garnet pyroxenite xenoliths and pyropic megacrysts in Scottish alkali basaltsScottish Journal of Geology, Vol. 39, No. 2, pp. 169-184.ScotlandMineralogy
DS200412-0424
2004
Hinton, R.W.Dawson, J.B., Hinton, R.W.Trace element content and partitioning in calcite, chromite and apatite in carbonatite, Phalaborwa, South Africa.Mineralogical Magazine, Vol. 67, 5, pp. 921-30.Africa, South AfricaCarbonatite, mineralogy
DS200412-2025
2003
Hinton, R.W.Upton, B.G.J., Aspen, P., Hinton, R.W.Garnet pyroxenite xenoliths and pyropic megacrysts in Scottish alkali basalts.Scottish Journal of Geology, Vol. 39, no. 2, pp. 169-184.Europe, ScotlandMineralogy
DS200612-0273
2006
Hinton, R.W.Coogan, L.A., Hinton, R.W.Do the trace element compositions of detrital zircons require Hadean continental crust?Geology, Vol. 34, 8, pp. 633-636.MantleGeothermometry
DS200812-1179
2008
Hinton, R.W.Tomlinson, E.I., Muller, W., Hinton, R.W., Klein Ben-David, O., Pearson, D.G., Harris, J.W.Metasomatic processes recorded in fibrous diamonds.Goldschmidt Conference 2008, Abstract p.A950.Canada, Northwest TerritoriesDeposit - Panda
DS1950-0277
1956
Hintrager, O.Hintrager, O.Suedwest afrika im der Deutschen ZeitUnknown., Southwest Africa, NamibiaDiamond, History, Politics
DS1900-0254
1904
Hintze, C.Hintze, C.Handbuch der MineralogieLeipzig: Veit And Co., Vol. 1, ( DIAMOND PP. 1-42 ). XEROX.GlobalKimberley, Mineralogy, Janlib, Kimberlite
DS1989-0642
1989
Hinz, K.Hinz, K., Fritsch, J., Kempter, E.H.K., et al.Thrust tectonics along the north-western continental margin ofSabah/BorneoGeologische Rundschau, Vol. 78, No. 3, pp. 705-730GlobalTectonics
DS1991-0718
1991
Hinze, H.J.Hinze, H.J., Vonfrese, R.R., Ravat, D.N.Mean magnetic contrasts between oceans and continentsTectonophysics, Vol. 192, No. 1-2, Jun. 10, pp. 117-127GlobalMantle, Geophysics -magnetics
DS202005-0736
2020
Hinze, W. JHinze, W. J,, Chandler, V.W.Reviewing the configuration and extent of the Midcontinent rift system.Precambrian Research, Vol. 342, 18p. PdfUnited States, Michigan, Ohio, Oklahomageophsyics - magnetics

Abstract: Uncertainty exists in the configuration and extent of the Midcontinent Rift System (MRS) because of deficiencies in geophysical data and limited information from outcrops and basement drill holes. Additional ambiguity is caused by misunderstanding the definition of continental rifts. Six principal problematic regions in mapping the MRS are described. Gravity and magnetic data, supported by drill hole and seismic reflection data, show that the Eastern Lake Superior rift segment of the MRS continues south from Lake Superior and connects to a much narrower rift in northern Lake Michigan. The eastern margin of this transition is ill defined because of the lack of definitive anomalies and supporting seismic and drill hole data, but is interpreted to occur near the U.S. - Canada border. The rift segment in southeastern Michigan intersects the Grenville Front and likely continues eastwards in modified form to near the boundary with Canada. Cross-cutting gravity and magnetic signatures may reflect Grenvillian overthrusts near the terminus of the MRS in Michigan. The proposed southerly extensions of both branches of the rift system into Oklahoma and Ohio are based primarily on positive gravity anomalies, but neither postulated extension appears to be associated with rifted troughs. Rather the gravity anomalies of the western branch are related to intrusive mafic rocks and those of the eastern branch are most likely related to deep crustal metamorphic rocks thrust into juxtaposition with less dense crust by Grenville orogenesis. Recent paleomagnetic investigations, in conjunction with high-resolution radiometric dating, imply that the MRS developed during the rapid southward movement of Laurentia during a quiescent period along its eastern continental margin. Massive magmatic activity accompanying the rifting was likely due to rising mantle material that was displaced by subducted lithosphere along the southern margin. The heated crust was made more ductile, fostering rifting due to extensional stresses. The Nipigon Embayment remains as a possible candidate for an early "third branch" of the MRS, but current evidence is insufficient to include the Fort Wayne "rift" as part of the MRS. Future studies of the MRS would be well-served by new age-dating and high-resolution seismic studies of the lithosphere.
DS1960-0596
1965
Hinze, W.J.Rudman, A.J., Summerson, C.H., Hinze, W.J.Geology of the Basement in Midwestern United StatesAmerican Association of Petroleum Geologists Bulletin., Vol. 49, PP. 894-904.GlobalMid-continent
DS1960-0681
1966
Hinze, W.J.Hinze, W.J., O'hara, N.W.Aeromagnetic Studies of Eastern Lake SuperiorIn: The Earth Beneath The Continents, American Geophys. Monogra, No. 10, PP. 95-110.GlobalMid-continent, Geophysics
DS1960-1129
1969
Hinze, W.J.Hinze, W.J., Merritt, D.W.Basement Rocks of the Southern Peninsula of MichiganIn: Studies of The Precambrian of The Michigan Basin. Michig, PP. 28-59.MichiganMid-continent, State Line, Rocky Mountains
DS1970-0578
1972
Hinze, W.J.O'hara, N.W., Hinze, W.J.Basement Geology of the Lake Michigan Area from Aeromagnetic Studies.Geological Society of America (GSA) Bulletin., Vol. 83, PP. 1771-1786.Michigan, WisconsinMid-continent, Geophysics
DS1970-0800
1973
Hinze, W.J.O'hara, N.W., Wold, R.J., Hinze, W.J.Regional Gravity and Magnetic Study of Southern Lake MichigaInternational Association GREAT LAKES RESEARCH, 16TH. CONFERENCE PROCEE, PP. 431-440.MichiganMid-continent
DS1970-0802
1973
Hinze, W.J.Oray, E., Hinze, W.J., O'hara, N.W.Gravity and Magnetic Evidence for the Eastern Termination Of the Lake Superior Syncline.Geological Society of America (GSA) Bulletin., Vol. 84, PP. 2763-2780.GlobalMid-continent
DS1970-0971
1974
Hinze, W.J.O'hara, N.W., Meguid, F., Hinze, W.J.Gravity and Magnetic Observations from Lake Erie and Lake Ontario Region.Geological Society of America (GSA), Vol. 6, No. 7, P. 896, (abstract.).Michigan, OhioMid-continent
DS1975-0105
1975
Hinze, W.J.Hinze, W.J., Kellogg, R.L., O'hara, N.W.Geophysical Studies of Basement Geology of Southern Peninsula of Michigan.American Association PET. GEOL. Bulletin., Vol. 59, PP. 1562-1584.MichiganMid-continent, Geophysics
DS1975-0370
1976
Hinze, W.J.O'hara, N.W., Hinze, W.J.Deep Crustal Implications of Regional Gravity and Magnetic Data.Geological Society of America (GSA), Vol. 8, No. 4, PP. 502-503. (abstract.).GlobalMid-continent
DS1975-0529
1977
Hinze, W.J.Hinze, W.J., Braile, L.W., Keller, G.R., Lidiak, E.G.A Tectonic Overview of the Central MidcontinentNational Technical Information Service NUREG 0382, 63P.GlobalMid-continent
DS1975-0556
1977
Hinze, W.J.Lidiak, E.G., Keller, G.R., Braile, L.W., Hinze, W.J.Rifting in the Midcontinent #1Eos, Vol. 59, No. 4, PP. 227-228. (abstract.).GlobalMid-continent
DS1975-0762
1978
Hinze, W.J.Hinze, W.J., Braile, L.W., Keller, G.R., Lidiak, E.G.Regional Tectonics of the Central Midcontinent, United StateGeological Association of Canada (GAC); Geological Society of America (GSA); MINERAL. Association CAN., Vol. 10, No. 7, P. 422. (abstract.).GlobalMid-continent
DS1975-0778
1978
Hinze, W.J.Keller, G.R., Hinze, W.J., Braile, L.W., Lidiak, E.G.A Tectonic Overview of the Central Mid-continentEos, Vol. 59, No. 4, P. 230. (abstract.).GlobalMid-continent
DS1975-0798
1978
Hinze, W.J.Lidiak, E.G., Keller, G.R., Braile, L.W., Hinze, W.J.Rifting in the Midcontinent #2Los Alamos Sci. Lab. Conference Proceedings, No. 7487, PP. 51-53. (abstract.).GlobalMid-continent
DS1975-0956
1979
Hinze, W.J.Bowman, P.L., Hinze, W.J., Chandler, V.W.Long Wavelength Gravity and Magnetic Anomalies of the Lake Superior Region.Geological Society of America (GSA), Vol. 11, No. 5, P. 226. (abstract.).GlobalMid-continent
DS1975-0961
1979
Hinze, W.J.Braile, L.W., Hinze, W.J., Keller, G.R., Lidiak, E.G.The Northeastern Extension of the New Madrid Seismic ZoneNational Technical Information Service NUREG CR/1014, PP. 74-99.GlobalMid-continent
DS1975-1097
1979
Hinze, W.J.Keller, E.G., Russel, D.R., Hinze, W.J., Reed, J.E., Geraci, P.C.A Bouguer Gravity Map of a Portion of the Central Midcontinent.Eos, Vol. 61, No. 5, P. 48.GlobalMid-continent
DS1975-1231
1979
Hinze, W.J.Soderberg, R.K., Keller, G.R., Braile, L.W., Hinze, W.J., et al.A Gravity and Tectonic Study of the Rough Creek Fault Zone And Related Features.National Technical Information Service NUREG CR/1014, PP. 134-164.GlobalMid Continent, New Madrid
DS1980-0074
1980
Hinze, W.J.Braile, L.W., Hinze, W.J., Sexton, J.L., Keller, G.R., Lidiak, E.An Integrated Geophysical and Geological Study of the TectonNational Technical Information Service NUREG CR 0977, PP. 17-28.GlobalMid-continent
DS1980-0175
1980
Hinze, W.J.Hinze, W.J., Braile, L.W., Keller, G.R., Lidiak, E.G.Models for Mid-continent TectonismIn: Continental Tectonics, Nat. Acad. Sciences Wash., PP. 73-83.GlobalMid-continent
DS1980-0188
1980
Hinze, W.J.Keller, G.R., Russell, D.R., Hinze, W.J., Reed, J.E., Geraci, P.Bouguer Gravity Anomaly Map of East Central Midcontinent Of the United States.National Technical Information Service NUREG CR/1663, 12P.GlobalMid-continent
DS1980-0264
1980
Hinze, W.J.O'hara, N.W., Hinze, W.J.Regional Basement Geology of Lake HuronGeological Society of America (GSA) Bulletin., Vol. 91, PT. 1, PP. 348-358.MichiganMid-continent
DS1980-0287
1980
Hinze, W.J.Reed, J.E., Hinze, W.J., Braile, L.W., Russell, D.R.Enhanced Gravity and Magnetic Anomaly Maps of the East Central Midcontintent.Geological Society of America (GSA), Vol. 12, No. 5, P. 254. (abstract.).GlobalMid-continent
DS1981-0236
1981
Hinze, W.J.Keller, G.R., Lidiak, E.G., Hinze, W.J., Braile, L.W.The Role of Rifting in the Tectonic Development of the Midcontinent #1Lpi Contrib., No. 457, PP. 51-52.GlobalMid-continent
DS1982-0114
1982
Hinze, W.J.Braile, L.W., Hinze, W.J., Sexton, J.L., Keller, G.R., Lidiak, E.Seismicity and Tectonics of the Midcontinent United StatesU.s. Nat. Science Foundation Proceedings of The Third International, Vol. 1, PP. 25-38.GlobalMid-continent
DS1982-0115
1982
Hinze, W.J.Braile, L.W., Hinze, W.J., Sexton, J.L., Keller, G.R., Lidiak.A Tectonic Study of the Extension of the New Madrid Fault Zone Near its intersection with the 38th Parallel Lineament.National Technical Information Service NUREG CR/2741, 84P.GlobalMid-continent
DS1982-0116
1982
Hinze, W.J.Braile, L.W., Keller, G.R., Hinze, W.J., Lidiak, E.G.An Ancient Rift Complex and its Relation to Contempory Seismicity in the New Madrid Seismic Zone.Tectonics, Vol. 1, No. 2, PP. 225-237.GlobalMid-continent
DS1982-0117
1982
Hinze, W.J.Braille, L.W., Hinze, W.J., Vonfrese, R.R.B.Gravity and Magnetic Anomaly Dat a AnalysisNational Technical Information Service NASA CR 169504, 1P.United StatesMid-continent, Geophysics
DS1982-0278
1982
Hinze, W.J.Hinze, W.J., Wold, R.J., O'hara, N.W.Gravity and Magnetic Anomaly Studies of Lake SuperiorGeological Society of America (GSA) MEMOIR., No. 156, PP. 203-221.Wisconsin, Minnesota, MichiganMid-continent
DS1982-0560
1982
Hinze, W.J.Sexton, J.L., Hinze, W.J., Von frese, R.R.B., Braile, L.W.Long-wavelength Aeromagnetic Anomaly Map of the Conterminous United States.Geology, Vol. 10, No. 7, PP. 364-369.GlobalMid-continent, Mississippi Embayment, Geophysics, Magsat
DS1982-0623
1982
Hinze, W.J.Von frese, R.R.B., Hinze, W.J., Braile, L.W.Regional North American Gravity and Magnetic Anomaly Correlations.Roy. Astron. Soc. Geophys. Journal, Vol. 69, PP. 745-761.United States, CanadaRegional Geophysics
DS1983-0143
1983
Hinze, W.J.Braile, L.W., Hinze, W.J., Vonfrese, R.R.B., Keller, G.R.Seismic Properties of the Crust and Uppermost Mantle of North America.National Technical Information Service NASA CR-175134, 48P.GlobalMid-continent
DS1983-0178
1983
Hinze, W.J.Coates, M.S., Haimson, B.C., Hinze, W.J., Van schmus, W.R.Introduction to the Illinois Deep Hole Project/Journal of Geophysical Research, Vol. 88, No. B9 SEPT. 10, PP. 7267-7750GlobalMid Continent
DS1983-0305
1983
Hinze, W.J.Hinze, W.J., Braile, L.W., Keller, G.R., Lidiak, E.G.Geophysical Geological Studies of Possible Extensions of The New Madrid Fault Zone.National Technical Information Service NUREG/CR 3174-V1, 101P.GlobalMid-continent
DS1983-0306
1983
Hinze, W.J.Hinze, W.J., Lidiak, E.G., Keller, G.R.Models for Midcontinent Tectonism: the Last 1600 Million Years.Geological Society of America (GSA), Vol. 15, No. 6, P. 596. (abstract.).GlobalMid Continent
DS1983-0307
1983
Hinze, W.J.Hinze, W.J., Lidiak, E.G., Reed, J.E., Keller, E.G., Braile, L.W.Geologic Significance of Regional Gravity and Magnetic Anomalies in the East Central Midcontinent.Geophysics, Vol. 48, No. 4, P. 449. (abstract.).GlobalMid-continent
DS1983-0350
1983
Hinze, W.J.Keller, G.R., Lidiak, E.G., Hinze, W.J., Braile, L.W.The Role of Rifting in the Tectonic Development of the Midcontinent, Usa #2Tectonophysics, Vol. 94, PP. 391-412.GlobalMid-continent
DS1983-0404
1983
Hinze, W.J.Lidiak, E.G., Hinze, W.J.Relation between Drill Hole Basement Lithology and Magnetic and Gravity Anomalies in the East Central Midcontinent.Geophysics, Vol. 48, No. 4, P. 448. (abstract.).GlobalMid-continent
DS1983-0405
1983
Hinze, W.J.Lidiak, E.G., Hinze, W.J., Mcphee, J.P.Tectonic Framework of Basement Rocks in the Eastern Midcontinent.Geological Society of America (GSA), Vol. 15, No. 6, P. 627. (abstract.).GlobalMid Continent
DS1984-0355
1984
Hinze, W.J.Hinze, W.J., Van schmus, W.R.Targeting Deep Scientific Drilling in the MidcontinentGeological Society of America (GSA), Vol. 16, No. 3, P. 146. (abstract.).MichiganMid-continent
DS1984-0455
1984
Hinze, W.J.Lidiak, E.G., Hinze, W.J.Speculations on Rift Zones and Basaltic Magmatism in the Precambrian of the East Central Midcontinent.Geological Society of America (GSA), Vol. 16, No. 3, P. 152. (abstract.).MichiganMid-continent
DS1985-0288
1985
Hinze, W.J.Hinze, W.J., et al.Geolhysical and Geoplogical Studies of Possible Extensions Of the New Madrid Fault Zone: Annual Report for 1983. Dated Oct. 82 to Sept. 83.Purdue University Department Geosciences, 60P.United StatesMidcontinent
DS1985-0692
1985
Hinze, W.J.Van schmus, W.R., Hinze, W.J.The Mid Continent Rift System (review)Annual Review Earth Science., Vol. 13, PP. 345-383.United StatesMid-continent
DS1986-0100
1986
Hinze, W.J.Braile, L.W., Hinze, W.J., Keller, G.R., Lidiak, E.G., Sexton, J.L.Tectonic development of the new Madrid rift complex Mississippi North AmericaTectonophysics, Vol. 131, No. 1/2, November 15, pp. 1-22MidcontinentTectonics
DS1986-0363
1986
Hinze, W.J.Hinze, W.J., Kane, M.F., O'Hara, N.W., Reford, M.S., Tanner, J., WeberThe utility of regional gravity and magnetic anomaly mapsSociety of Exploration Geophysicists, Special Volume, 400pUnited States, CanadaGeophysics
DS1986-0725
1986
Hinze, W.J.Sexton, J.L., Braile, L.W., Hinze, W.J., Campbell, M.J.Seismic reflection profiling studies of a buried Precambrian rift beneath the Wabash Valley fault zoneGeophysics, Vol. 51, No. 3, March pp. 640-660GlobalMississippi embayment, Geophysics
DS1988-0307
1988
Hinze, W.J.Hinze, W.J., Braile, L.W., Keller, G.R., Lidiak, E.G.Models for midcontinent tectonism: an updateReviews of Geophysics, Vol. 26, No. 4, November pp. 699-717Arkansas, MidcontinentGeophysics, Tectonics
DS1988-0308
1988
Hinze, W.J.Hinze, W.J., Kelly, W.C.Scientific drilling into the Midcontinent rift systemEos, Vol. 69, No. 51, December 20, p. 1649, 1656-57MidcontinentRift
DS1989-0168
1989
Hinze, W.J.Braile, L.W., Hinze, W.J.Structure and tectonics of the MidcontinentGeological Society of America (GSA) North Central Section, Notre Dame Indiana April, Symposia being heldMidcontinentStructure, Ad in GSA News Jan 89 on
DS1989-0209
1989
Hinze, W.J.Cannon, W.F., Schulz, K.J., Hinze, W.J., Green, A.G.Precambrian terranes beneath northern Lake Michigan defined by seismic and gravity analysis35th. Annual Institute On Lake Superior Geology, Proceedings And, pp. 14-15MichiganMidcontinent, Seismics, Geophysics, Tect
DS1989-0243
1989
Hinze, W.J.Chandler, V.W., McSwiggen, P.L., Morey, G.B., Hinze, W.J., AndersonInterpretation of seismic reflection, gravity and magnetic dat a acrossAmerican Association Petrol. Geologists, Vol. 73, No. 3, March pp. 261-275Wisconsin, Minnesota, Iowa, MidcontinentTectonics, Geophysics
DS1989-0361
1989
Hinze, W.J.Dods, S.W., Hinze, W.J., Keating, P., Smith, J.G.Magnetic and gravity anomaly maps of the Lake Huron region35th. Annual Institute On Lake Superior Geology, Proceedings And, pp. 21Michigan, OntarioGeophysics
DS1989-0643
1989
Hinze, W.J.Hinze, W.J., McGinnis, L.D., Cannon, W.F., Milkereit, B., SextonStructure of the midcontinent rift system in E Lake Superior; preliminary35th. Annual Institute On Lake Superior Geology, Proceedings And, pp. 24MidcontinentGeophysics, Tectonics
DS1989-0644
1989
Hinze, W.J.Hinze, W.J., Shaw, B.R.Geographic information system symposium: integrating technology and geoscience applicationsThe Leading Edge, Vol. 8, No. 9, September pp. 52-53GlobalGIS, Overview
DS1990-0701
1990
Hinze, W.J.Hinze, W.J., Braile, L.W., Chandler, V.W.A geophysical profile of the southern margin of The midcontinent Rift system in western Lake SuperiorTectonics, Vol. 9, No. 2, April pp. 303-310MidcontinentGeophysics, Midcontinent Rift
DS1991-0014
1991
Hinze, W.J.Allen, D.J., Hinze, W.J.The origin and significance of the Wisconsin gravity minimuMGeological Society of America, Abstract Volume, Vol. 23, No. 3, March p. 1WisconsinGeophysics -gravity, Tectonics
DS1991-0217
1991
Hinze, W.J.Cannon, W.F., Lee, M.Y.W., Hinze, W.J., Schulz, K.J., Green, A.G.Deep crustal structure of the Precambrian basement beneath northern LakeMichigan, midcontinent North AmericaGeology, Vol. 19, No. 3, March pp. 207-210MichiganTectonics, Structure -crustal
DS1991-0719
1991
Hinze, W.J.Hinze, W.J., Vonfrese, R.R.Magnetics in geoexplorationP.il.a.s.-ear, Vol. 99, No. 4, December pp. 515-547GlobalGeophysics -magnetics, Exploration techniques
DS1991-1057
1991
Hinze, W.J.Mariano, J., Hinze, W.J.A geophysical investigation of the midcontinent rift and the associated crustal structure in eastern Lake SuperiorGeological Society of America, Abstract Volume, Vol. 23, No. 3, March p. 26MidcontinentGeophysics, Tectonics -rift
DS1991-1883
1991
Hinze, W.J.Woelk, T.S., Hinze, W.J.Model of the midcontinent rift system in northeastern KansasGeology, Vol. 19, No. 3, March pp. 277-280KansasTectonics, Midcontinent rift
DS1992-0017
1992
Hinze, W.J.Allen, D.J., Hinze, W.J.Wisconsin gravity minimum: solution of a geologic and geophysical puzzle and implications for cratonic evolutionGeology, Vol. 20, No. 6, June pp. 515-518WisconsinGeophysics -gravity, Craton
DS1992-0214
1992
Hinze, W.J.Cannon, W.F., Hinze, W.J.Speculations on the origin of the North American Midcontinent RiftTectonophysics, Vol. 213, No. 1-2, special issue, pp. 49-55MidcontinentGeodynamics, Tectonics
DS1992-0710
1992
Hinze, W.J.Hinze, W.J., Allen, D.J., Fox, A.J., Sunwood, D., Woelk, T., GreenGeophysical investigations and crustal of the North American Midcontinent rift systemTectonophysics, Vol. 213, No. 1-2, special issue, pp. 17-32MidcontinentTectonics, Geophysics
DS1992-0711
1992
Hinze, W.J.Hinze, W.J., Allen, D.J., Mariano, J.Lithosphere of the Midcontinent Rift region: progress and problemsEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 319MidcontinentMidcontinent Rift, Lithosphere
DS1992-0998
1992
Hinze, W.J.Mariano, J., Hinze, W.J.Magnetic modeling of complexly magnetized bodies with implications to the structure of the midcontinent rift in eastern Lake SuperiorEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p. 320OntarioMidcontinent Rift, Geophysics -magnetics
DS1992-1257
1992
Hinze, W.J.Ravat, D.N., Hinze, W.J., Vonfrese, R.R.Analysis of magsat magnetic contrasts across Africa and South-AmericaTectonophysics, Vol. 212, No. 1-2, Oct. 1, pp. 59-76.Africa, South AmericaGeophysics -magnetics, Magsat, Remote sensing
DS1993-1284
1993
Hinze, W.J.Ravat, D.H., Hinze, W.J., Taylor, P.T.European tectonic features observed by MAGSATTectonophysics, Vol. 220, No. 1-4, April 15, pp. 157-173.EuropeGeophysics -MAGSAT, Tectonics, Remote sensing
DS1994-0617
1994
Hinze, W.J.Gibb, R.A., Hinze, W.J., Thomas, M.D.Potential field studies of continental rifts -The Great Lakes region:introduction.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 617-618.Ontario, MichiganGeophysics -seismics, Tectonics -Midcontinent rift
DS1994-0774
1994
Hinze, W.J.Hinze, W.J.The eastern arm of the midcontinent rift: progress and problemsGeological Society of America Abstracts, Vol. 26, No. 5, April p. 20. Abstract.GlobalTectonics, Midcontinent
DS1994-1103
1994
Hinze, W.J.Mariano, J., Hinze, W.J.Gravity and magnetic models of the Midcontinent Rift in eastern LakeSuperior.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 661-674.Ontario, MichiganGeophysics -gravity, magnetics, Tectonics -Midcontinent rift
DS1994-1104
1994
Hinze, W.J.Mariano, J., Hinze, W.J.Structural interpretation of Midcontinent Rift in east Lake Superior from seismic reflection, potential fieldCanadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 619-628Ontario, MichiganGeophysics -seismics, Tectonics -Midcontinent rift
DS1994-1105
1994
Hinze, W.J.Mariano, J., Hinze, W.J.Structural interpret. Midcontinent Rift in eastern Lake Superior from seismic reflection and potential field.Canadian Journal of Earth Sciences, Vol. 31, No. 4, April pp. 619-628.Ontario, MichiganGeophysics -seismics, Tectonics -Midcontinent rift
DS1995-0023
1995
Hinze, W.J.Allen, D.J., Braile, L.W., Hinze, W.J., Mariano, J.The midcontinent rift system United States (US): a major Proterozoic continental riftContinental Rifts: evolution, structure, tectonics, No. 25, pp. 375-408Michigan, Wisconsin, Kansas, Lake Superior regionGeophysics - seismics, gravity, Structure
DS1995-0024
1995
Hinze, W.J.Allen, D.J., Braile, L.W., Hinze, W.J., Mariano, J.The midcontinent rift system United States (US): a major Proterozoic continental riftContinental Rifts: evolution, structure, tectonics, No. 25, pp. 375-408.Michigan, Wisconsin, Kansas, Lake Superior regionGeophysics - seismics, gravity, Structure
DS1995-0182
1995
Hinze, W.J.Bott, M.H.P., Hinze, W.J.Methods of investigation: potential field methodsContinental Rifts: evolution, structure, tectonics, No. 25, pp. 93-98North AmericaGeophysics -gravity, magnetics
DS1995-0183
1995
Hinze, W.J.Bott, M.H.P., Hinze, W.J.Methods of investigation: potential field methodsContinental Rifts: evolution, structure, tectonics, No. 25, pp. 93-98.North AmericaGeophysics -gravity, magnetics
DS1995-0803
1995
Hinze, W.J.Hinze, W.J., Allen, D.J., Braile, L.W., Mariano, J.The Midcontinent rift system: an overviewBasement Tectonics 10, held Minnesota Aug 92, pp. 3-6.MidcontinentTectonics
DS1995-1169
1995
Hinze, W.J.Mariano, J., Hinze, W.J.Integrated potential field and seismic reflection studies of Midcontinent rift in eastern Lake Superior.Basement Tectonics 10, held Minnesota Aug 92, pp. 11-14.MidcontinentTectonics, Geophysics -seismics
DS1996-0629
1996
Hinze, W.J.Hildenbrand, T.G., Blakely, R.J., Hinze, W.J., et al.Aeromagnetic survey over the U.S. to advance geomagnetic researchEos, Vol. 77, No. 28, July 9, pp. 265, 268United StatesGeophysics -aeromagnetics, Brief overview
DS1996-0632
1996
Hinze, W.J.Hinze, W.J.The crust of the northern United States craton: a search for beginningsGeological Society of America (GSA) Special Paper, No. 308, pp. 187-203.MidcontinentCraton, Tectonics
DS2003-0583
2003
Hinze, W.J.Hildenbrand, T.G., Keller, R.G., Blakely, R., Hinze, W.J.Need for a U.S. high altitude magnetic surveyGeological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 446.United StatesGeophysics
DS2003-0586
2003
Hinze, W.J.Hinze, W.J.Bouguer reduction density, why 2.67?Geophysics, Vol. 68, 5, pp. 1559-60.GlobalGeophysics - discontinuity
DS200412-0827
2003
Hinze, W.J.Hildenbrand, T.G., Keller, R.G., Blakely, R., Hinze, W.J.Need for a U.S. high altitude magnetic survey.Geological Society of America, Annual Meeting Nov. 2-5, Abstracts p. 446.United StatesGeophysics
DS200412-0832
2003
Hinze, W.J.Hinze, W.J.Bouguer reduction density, why 2.67?Geophysics, Vol. 68, 5, pp. 1559-60.TechnologyGeophysics - discontinuity
DS200512-0434
2005
Hinze, W.J.Hinze, W.J., Aiken, C., Brozena, J., Coakley, Dater, Flanagan, Forsberg, Hildenbrand, Keller, KelloggNew standards for reducing gravity data: the North American gravity database.Geophysics, Vol. 70, 4, pp. J25-J32.Canada, United StatesGeophysics - gravity
DS1998-0620
1998
Hippertt, J.F.Hippertt, J.F.Phyllonitization and development of kilometer size extension gashes in continental scale strike slip zoneJournal of Struct. Geol, Vol. 20, No. 4, Apri, pp. 433-437Brazil, GoiasStructure, Tectonics
DS2003-0587
2003
Hiraga, T.Hiraga, T., Anderson, I.M., Kohlstedt, D.L.Chemistry of grain boundaries in mantle rocksAmerican Mineralogist, Vol. 88, 7 July, pp. 1015-19.MantleSTEM, EDX, chemical segregation, Geochemistry
DS2003-0588
2003
Hiraga, T.Hiraga, T., Anderson, I.M., Kohlstedt, D.L.Chemistry of grain boundaries in mantle rocksAmerican Mineralogist, Vol. 88, pp. 1015-19.MantleBlank
DS2003-0597
2003
Hiraga, T.Holtzman, B.K., Kohlstedt, D.L., Zimmerman, M.E., Heidelbach, F., Hiraga, T.Melt segregation and strain partitioning: implications for seismic anisotropy and mantleScience, No. 5637, August 29,p. 1227-29.MantleGeophysics - seismic
DS200412-0833
2003
Hiraga, T.Hiraga, T., Anderson, I.M., Kohlstedt, D.L.Chemistry of grain boundaries in mantle rocks.American Mineralogist, Vol. 88, 7 July, pp. 1015-19.MantleSTEM, EDX, chemical segregation Geochemistry
DS200412-0845
2003
Hiraga, T.Holtzman, B.K., Kohlstedt, D.L., Zimmerman, M.E., Heidelbach, F., Hiraga, T., Hustoft, J.Melt segregation and strain partitioning: implications for seismic anisotropy and mantle flow.Science, No. 5637, August 29,p. 1227-29.MantleGeophysics - seismic
DS200712-0439
2007
Hiraga, T.Hiraga, T., Hirschmann, M.M., Kohlstedt, D.L.Equilibrium interface segregation in the diopside forsterite system II: applications of interface enrichment to mantle geochemistry.Geochimica et Cosmochimica Acta, Vol. 71, 5, pp. 1281-1289.MantleGeochemistry
DS200912-0300
2009
Hiraga, T.Hiraga, T., Kohlstedy, D.L.Systematic distribution of incompatible elements in mantle peridotite: importance of intra and inter granular melt like components.Contributions to Mineralogy and Petrology, Vol. 158, 2, pp. 149-167.MantlePeridotite
DS1993-0725
1993
Hirahara, K.Iyer, H.M., Hirahara, K.Seismic tomography, theory and practiceChapman and Hall, 842p. approx. $ 300.00BookTomography, Geophysics -seismic
DS2003-0720
2003
Hirahara, K.Kito, T., Shibutani, T., Hirahara, K.Scattering objects in the lower mantle beneath north eastern Chin a observed with aPhysics of the Earth and Planetary Interiors, Vol. 138, 1, pp. 55-69.ChinaBlank
DS200412-1009
2003
Hirahara, K.Kito, T., Shibutani, T., Hirahara, K.Scattering objects in the lower mantle beneath north eastern Chin a observed with a short period sesimic array.Physics of the Earth and Planetary Interiors, Vol. 138, 1, pp. 55-69.ChinaGeophysics - seismics
DS2003-1251
2003
Hirahara, M.Seki, K., Hirahara, M., Hoshino, M., et al.Cold ions in the hot plasma sheet of Earth's magnetotailNature, Vol. 6932, April 10, pp. 589-91.MantleGeophysics - magnetics
DS200412-1785
2003
Hirahara, M.Seki, K., Hirahara, M., Hoshino, M., et al.Cold ions in the hot plasma sheet of Earth's magnetotail.Nature, Vol. 6932, April 10, pp. 589-91.MantleGeophysics - magnetics
DS1985-0476
1985
Hirai, H.Nakazawa, H., Tagai, T., Hirai, H., Satow, Y.X-ray Section Topographs of a Cube Shaped DiamondMineralogical Journal, Vol. 12, No. 6, pp. 245-250GlobalDiamond Morphology
DS1988-0721
1988
Hirai, H.Uto, K., Hirai, H., Goto, K., Arai, S.K-Ar ages of carbonate and mantle nodule bearing lamprophyre dikes fromShingu, central Shikoku, southwest JapanGeochemical JOurnal, Vol. 21, No. 6, pp. 283-290JapanBlank
DS1991-0720
1991
Hirai, H.Hirai, H., Ken-Ichi KondoModified phases of diamond formed under shock compression and rapidquenchingScience, Vol. 253, August 16, pp. 772-774GlobalDiamond morphology, Mineralogy
DS1998-0621
1998
Hirai, H.Hirai, H.A possible genesis of cosmic diamond: transition of C 60 fullerene todiamond.Ima 17th. Abstract Vol., p. A 22, abstractGlobalDiamond spectroscopy, Carbon
DS200412-1399
2004
HirajamaNakamura, D., Svojtka, K., Naemura, T., HirajamaVery high pressure >4 GPa eclogite associated with the Moldanubian Zone garnet peridotite Nove Dory, Czech Republic.Journal of Metamorphic Geology, Vol. 22, 6, pp. 593-603.Europe, Czech RepublicEclogite, UHP
DS1990-1285
1990
Hirajima, T.Ruyuan Zhang, Hirajima, T., Banno, S., Ishiwatari, A., Jiaju Li, BolinCoesite -eclogite from Donghai area, Jiangsu Province in ChinaInternational Mineralogical Association Meeting Held June, 1990 Beijing China, Vol. 2, extended abstract p. 923-924ChinaEclogite, Coesite
DS1995-2133
1995
Hirajima, T.Zhang, R.Y., Hirajima, T., Banno, S., Bolin Cong, Liou, J.Petrology of ultrahigh pressure rocks from the southern Su Lu region, eastern China.Journal of Metamorphic Geology, Vol. 13, No. 6, Nov. pp. 659-676.ChinaMetamorphic rocks, Deposit -Su-Lu region
DS2001-0203
2001
Hirajima, T.Compagnoni, R., Hirajima, T.Superzoned garnets in the coesite bearing Brossasco Isasca unit, Dora Maira Massif, origin of whiteschistsLithos, Vol. 57, No. 4, July pp. 219-36.AlpsCoesite - not specific to diamonds
DS200612-0965
2005
Hirajima, T.Nakamura, D., Hirajima, T.Experimental evaluation of garnet clinopyroxene geothermometry as applied to eclogites.Contributions to Mineralogy and Petrology, Vol. 150, 6, Dec. pp. 581-588.MantleEclogite
DS201312-0436
2013
Hirajima, T.Janak, M., Krogh Ravna, E.J., Kullerud, K., Yoshida, K., Milovsky, R., Hirajima, T.Discovery of diamond in the Tromso Nappe, Scandinavian Caledonides ( N. Norway).Journal of Metamorphic Geology, Vol. 31, 6, pp. 691-703.Europe, NorwayMicrodiamonds in gneiss
DS201504-0203
2015
Hirajima, T.Janak, M., Froitzheim, N., Yoshida, K., Sasinkova, V., Nosko, M., Kobayashi,T., Hirajima, T., Vrabec, M.Diamond in metasedimentary crustal rocks from Pohorje, eastern Alps: a window to deep continental subductionJournal of Metamorphic Geology, Vol. 33, 5, pp. 495-512.Europe, SloveniaSubduction
DS1998-0812
1998
Hiramatsu, Y.Kubo, A., Hiramatsu, Y.On presence of seismic anisotropy in the asthenosphere beneath continents and its dependence - plate velocityPure and Applied Geophys., Vol. 151, No. 2-4, Mar. 1, pp. 281-305.MantleGeophysics - seismics, Geodynamics
DS200612-0584
2006
Hirano, N.Hirano, N.Volcanism in response to plate flexure.Science, Vol. 313, 5792, Sept. 8, pp. 1426-1428.MantleTectonics
DS200712-1197
2007
Hirano, N.Yamamoto, J., Kagi, H., Kawakami, Y., Hirano, N., Nakamura, M.Paleo-Moho depth determined from the pressure of CO2 fluid inclusions: Raman spectroscopic barometry of mantle crust derived rocks.Earth and Planetary Science Letters, Vol. 253, 3-4, pp. 369-377.MantleGeothermometry
DS1982-0453
1982
Hirano, S.Naka, S., Suwa, Y., Hirano, S.Study of Graphite-diamond Transformation Process by Electrothermal Analysis.Proceedings high pressure AND RESEARCH INDUSTRY 8TH. AIRAPT Conference, Vol. 1, PP. 365-368.GlobalResearch
DS1981-0310
1981
Hirano, S.I.Naka, S., Suwa, Y., Takeda, Y., Hirano, S.I.Some Observations of Graphite Diamond Transformation by Electro Thermal Analysis.Nippon Kagai Kaishi, (1972), No. 9, PP. 1468-1473.GlobalMineralogy
DS1985-0682
1985
Hirano, S.I.Tsuzuki, A., Hirano, S.I., Naka, S.Influencing Factors for Diamond Formation from Several Starting Carbons.Journal of MATERIAL SCIENCE., Vol. 20, No. 6, JUNE PP. 2260-2264.GlobalBlank
DS201701-0027
2016
Hirano. N.Pilet, S., Abe, N., Rochat, L., Kaczmarek, M-A., Hirano. N., Machida, S., Buchs, D.M., Baumgartner, P.O., Muntener, O.Pre-subduction metasomatic enrichment of the oceanic lithosphere induced by plate flexure.Nature Geoscience, Vol. 9, pp. 898-903.MantleSubduction

Abstract: Oceanic lithospheric mantle is generally interpreted as depleted mantle residue after mid-ocean ridge basalt extraction. Several models have suggested that metasomatic processes can refertilize portions of the lithospheric mantle before subduction. Here, we report mantle xenocrysts and xenoliths in petit-spot lavas that provide direct evidence that the lower oceanic lithosphere is affected by metasomatic processes. We find a chemical similarity between clinopyroxene observed in petit-spot mantle xenoliths and clinopyroxene from melt-metasomatized garnet or spinel peridotites, which are sampled by kimberlites and intracontinental basalts respectively. We suggest that extensional stresses in oceanic lithosphere, such as plate bending in front of subduction zones, allow low-degree melts from the seismic low-velocity zone to percolate, interact and weaken the oceanic lithospheric mantle. Thus, metasomatism is not limited to mantle upwelling zones such as mid-ocean ridges or mantle plumes, but could be initiated by tectonic processes. Since plate flexure is a global mechanism in subduction zones, a significant portion of oceanic lithospheric mantle is likely to be metasomatized. Recycling of metasomatic domains into the convecting mantle is fundamental to understanding the generation of small-scale mantle isotopic and volatile heterogeneities sampled by oceanic island and mid-ocean ridge basalts.
DS200612-0585
2006
Hirao, N.Hirao, N., Kondo, T., Ohtani, E., Kikegawa, T.Post hollandite phase in KAlSi308 as a possible host mineral of potassium in the Earth's lower mantle.International Mineralogical Association 19th. General Meeting, held Kobe, Japan July 23-28 2006, Abstract p. 130.MantleMineralogy
DS200812-0471
2008
Hirao, N.Hirao, N., Ohtani, E., Kondo, T., Sakari, T., Kikegawa, T.Hollandite II phase in KAiSi3O8 as a potential host mineral of potassium in the Earth's lower mantle.Physics of the Earth and Planetary Interiors., Vol. 166, 1-2, pp. 97-104.MantlePotassium
DS200912-0523
2009
Hirao, N.Murakami, M., Oshishi, Y., Hirao, N., Hirose, K.Elasticity of MgO to 130 GPa: implications for lower mantle mineralogy.Earth and Planetary Science Letters, Vol. 277, 1-2, pp. 123-129.MantleMineralogy
DS201212-0385
2012
Hirao, N.Kudo, Y., Hirose, K.,Murakami, M., Asahara, Y., Ozawa, H., Ohishi, Y., Hirao, N.Sound velocity measurements of CaSiO3 perovskite to 133 Gpa an implications for lowermost mantle seismic anomalies.Earth and Planetary Science Letters, Vol. 349-350 pp. 1-7.MantlePerovskite
DS201212-0503
2012
Hirao, N.Murakami, M., Ohishi, Y., Hirao, N., Hirose, K.A perovskite lower mantle inferred from high pressure, high temperature sound velocity data.Journal of the Geological Society of India, Vol. 80, 1, p. 147. Brief reviewMantlePerovskite
DS201212-0504
2012
Hirao, N.Murakami, M., Ohishi, Y., Hirao, N., Hirose, K.A perovskite lower mantle inferred from high pressure, high temperature sound velocity data.Nature, Vol. 485, May 3, pp. 90-94.MantlePerovskite
DS201412-0542
2014
Hirao, N.Maeda, F., Ohtani, E., Kamada, S., Sakamaki, T., Ohishi, Y., Hirao, N.The reactions in the MgCO3-SiO2 system in the slabs subducted into the lower mantle and formation of deep diamond.V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of Sciences International Symposium Advances in high pressure research: breaking scales and horizons ( Courtesy of N. Poikilenko), Held Sept. 22-26, 1p. AbstractSouth America, BrazilCarbon
DS201412-0645
2014
Hirao, N.Ohira, I., Ohtani, E., Sakai, T., Miyahara, M., Hirao, N., Ohishi, Y., Nishijima, M.Stability of a hydrous delta phase AlOOH-MgSiO2(OH)2, and a mechanism for water transport into the base of lower mantle.Earth and Planetary Science Letters, Vol. 401, pp. 12-17.MantleWater
DS201503-0164
2015
Hirao, N.Ohtani, E., Amaike, Y., Kamada, S., Sakamaki, T., Hirao, N.Stability of hydrous phase H MgSi04H2 under lower mantle conditions.Geophysical Research Letters, Vol. 41, 23, pp. 8283-8287.MantleMineralogy
DS201704-0638
2017
Hirao, N.Maeda, F., Ohtani, E., Kamada, S., Sakamaki, T., Hirao, N., Ohishi, Y.Diamond formation in the deep lower mantle: a high pressure reaction of MgCO3 and SiO2.Nature Scientific reports, Jan. 13, 7p. PdfMantleDiamond, genesis

Abstract: Diamond is an evidence for carbon existing in the deep Earth. Some diamonds are considered to have originated at various depth ranges from the mantle transition zone to the lower mantle. These diamonds are expected to carry significant information about the deep Earth. Here, we determined the phase relations in the MgCO3-SiO2 system up to 152?GPa and 3,100?K using a double sided laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction. MgCO3 transforms from magnesite to the high-pressure polymorph of MgCO3, phase II, above 80?GPa. A reaction between MgCO3 phase II and SiO2 (CaCl2-type SiO2 or seifertite) to form diamond and MgSiO3 (bridgmanite or post-perovsktite) was identified in the deep lower mantle conditions. These observations suggested that the reaction of the MgCO3 phase II with SiO2 causes formation of super-deep diamond in cold slabs descending into the deep lower mantle.
DS200812-0642
2008
Hiraoka, N.Lee, S.K., Lin, J.F., Cai, Y.Q., Hiraoka, N., Eng, P.J., Okuchi, T., Mao, H., Meng, Y., Hu, M.Y.,Chow, P.X ray Raman scattering study of MgSi)3 glass at high pressure: implication for triclustered MgSiO3 melt in Earth's mantle.Proceedings of National Academy of Sciences USA, Vol. 105, 23, June 10, pp. 7925-7929.MantleMelting
DS202201-0035
2021
Hirata, A.Pratesi, G., Franz, a., Hirata, A.It is hard to be a gem in a rhinestone world: a diamond Museum collection between history and science. ( Firenza)Geoheritage, Vol. 13, 103 Europe, ItalyFTIR spectroscopy

Abstract: The goal of this work is to investigate the diamond collection preserved at the Natural History Museum of the University of Firenze (MSN-FI) using a multidisciplinary approach. The mixed methods combine historical research with spectroscopic techniques to gain a deeper understanding of this collection of great historical, scientific and gemmological interest. This study concerns the analysis of 61 diamonds that are relatively small in both size and weight, mostly unworked and sometimes rich in inclusions. These specimens were acquired by MSN-FI from diverse collectors and institutions from 1824 until the most recent acquisitions in the 1990s. The FTIR spectroscopy was performed on 45 specimens. The results show the physical classification of diamonds in three groups (IaAB, IaA, and IaB) and reveal the presence of hydrogen as ethylene -CH?=?CH- or vinylidene?>?C?=?CH2 group.
DS2002-0872
2002
Hirata, T.Komiya, T., Maruyama, S., Hirata, T., Yurimoto, H.Petrology and geochemistry of MORB and OIB in the mid-Archean north pole regionInternational Geology Review, Vol. 44, No. 11, Nov. pp. 988-1016.Australia, westernMantle - geochronology
DS200412-1671
2004
Hirata, T.Rino, S., Komiya, T., Windley, B.F., Katayama, I., Motoki, A., Hirata, T.Major episodic increase of continental crust growth determined from zircon ages river sands: implications for mantle overturns iPhysics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 369-394.MantleGeochronology
DS200612-0599
2006
Hirata, T.Horie, K., Komiya, T., Maruyama, S., Hirata, T., Hidaka, H., Windley, B.F.4.2 Ga zircon xenocryst in an Acasta gneiss from northwestern Canada: evidence for early continental crust.Geology, Vol.34, 4, April pp. 245-248.Canada, Northwest TerritoriesGeochronology, spectrometry
DS201512-1935
2015
Hirata, T.Kon, Y., Araoka, D., Ejima, T., Hirata, T.Rapid and precise determination of major and trace elements in CCRMP and USGS geochemical reference samples using femtosecond laser ablation ICP-MS.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 245-250.TechnologyCarbonatite

Abstract: We measured 10 major (SiO2, TiO2, Al2O3, total Fe2O3, MnO, MgO, CaO, Na2O, K2O, and P2O5) and 32 trace (Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Pb, Th, and U) elements in 16 geochemical reference samples (AGV-1, AGV-2, BCR-1, BCR- 2, BHVO-2, BIR-1a, DNC-1a, G-2, GSP-1, GSP-2, MAG-1, QLO-1, RGM-1, RGM-2, SGR-1b, and STM-1) distributed by United States Geological Survey (USGS) and three reference rock samples (SY-2, SY-3, and MRG-1) provided by Canadian Certifi ed Reference Materials Project (CCRMP) using inductively coupled plasma -mass spectrometry coupled with the femtosecond laser ablation sample introduction technique (fsLA-ICP-MS). Before the elemental analysis, fused glassbeads were prepared from the mixture of sample powder and high-purity alkali fl ux with a mixing ratio of 1:10. The abundances of the major and trace elements were externally calibrated by using glass beads containing the major and trace elements prepared from 17 Geological Survey of Japan (GSJ) geochemical reference samples (JB-1, JB-1a, JB-2, JB-3, JA-1, JA-2, JA-3, JR-1, JR-2, JR-3, JP-1, JGb-1, JGb-2, JG-1a, JG- 2, JG-3, and JSy-1). Typical analysis repeatabilities for these geochemical reference samples were better than 3% for Al2O3 and Na2O; <5% for SiO2, TiO2, total Fe2O3, MnO, MgO, CaO, K2O, P2O5, Zn, Rb, Sr, Zr, Nb, Ba, Nd, and U; <8% for Sc, V, Cr, Co, Y, Cs, La, Ce, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Pb, and Th; <11% for Ni and Cu. These data clearly demonstrate that high analytical repeatability can be achieved by the fsLA-ICP-MS technique with glass beads made from 0.5 g larger samples.
DS201906-1315
2019
Hirata, T.Litasov, K.D., Kagi, H., Voropaev, S.A., Hirata, T., Ohfuji, H., Ishibashi., Makino, Y., Bekker, T.B., Sevastyanov, V.S., Afanasiev,V.P., Pokhilenko, N.P.Comparison of enigmatic diamonds from the Tolbachik arc volcano ( Kamchatka) and Tibetan ophiolites: assessing the role of contamination by synthetic materials. Gondwana Research, in press available 38p.Russia, Asia, Tibetdeposit - Tolbachik

Abstract: The enigmatic appearance of cuboctahedral diamonds in ophiolitic and arc volcanic rocks with morphology and infrared characteristics similar to synthetic diamonds that were grown from metal solvent requires a critical reappraisal. We have studied 15 diamond crystals and fragments from Tolbachik volcano lava flows, using Fourier transform infrared spectrometry (FTIR), transmission electron microscopy (TEM), synchrotron X-ray fluorescence (SRXRF) and laser ablation inductively coupled plasma mass-spectrometry (LA-ICP-MS). FTIR spectra of Tolbachik diamonds correspond to typical type Ib patterns of synthetic diamonds. In TEM films prepared using focused ion beam technique, we find Mn-Ni and Mn-Si inclusions in Tolbachik diamonds. SRXRF spectra indicate the presence of Fe-Ni and Fe-Ni-Mn inclusions with Cr, Ti, Cu, and Zn impurities. LA-ICP-MS data show variable but significantly elevated concentrations of Mn, Fe, Ni, and Cu reaching up to 70?ppm. These transition metal concentration levels are comparable with those determined by LA-ICP-MS for similar diamonds from Tibetan ophiolites. Mn-Ni (+Fe) solvent was widely used to produce industrial synthetic diamonds in the former USSR and Russia with very similar proportions of these metals. Hence, it appears highly probable that the cuboctahedral diamonds recovered from Kamchatka arc volcanic rocks represent contamination and are likely derived from drilling tools or other hard instruments. Kinetic data on diamond dissolution in basaltic magma or in fluid phase demonstrate that diamond does not form under the pressures and temperature conditions prevalent within the magmatic system beneath the modern-day Klyuchevskoy group of arc volcanoes. We also considered reference data for inclusions in ophiolitic diamonds and compared them with the composition of solvent used in industrial diamond synthesis in China. The similar inclusion chemistry close to Ni70Mn25Co5 for ophiolitic and synthetic Chinese diamonds scrutinized here suggests that most diamonds recovered from Tibetan and other ophiolites are not natural but instead have a synthetic origin. In order to mitigate further dubious reports of diamonds from unconventional tectonic settings and source rocks, we propose a set of discrimination criteria to better distinguish natural cuboctahedral diamonds from those produced synthetically in industrial environments and found as contaminants in mantle- and crust-derived rocks.
DS202004-0537
2020
Hirata, T.Tamarova, A.P., Marchenko, E.I., Bobrov, A.V., Eremin, N.N., Zinovera, N.G., Irifune, T., Hirata, T., Makino, Y.Interphase REE partitioning at the boundary between the Earth's transition zone and lower mantle: evidence from experiments and atomistic modeling.Minerals MDPI, Vol. 10, 10030262 14p. PdfMantleREE

Abstract: Trace elements play a significant role in interpretation of different processes in the deep Earth. However, the systematics of interphase rare-earth element (REE) partitioning under the conditions of the uppermost lower mantle are poorly understood. We performed high-pressure experiments to study the phase relations in key solid-phase reactions CaMgSi2O6 = CaSiO3-perovskite + MgSiO3-bridgmanite and (Mg,Fe)2SiO4-ringwoodite = (Mg,Fe)SiO3-bridgmanite + (Mg,Fe)O with addition of 1 wt % of REE oxides. Atomistic modeling was used to obtain more accurate quantitative estimates of the interphase REE partitioning and displayed the ideal model for the high-pressure minerals. HREE (Er, Tm, Yb, and Lu) are mostly accumulated in bridgmanite, while LREE are predominantly redistributed into CaSiO3. On the basis of the results of experiments and atomistic modeling, REE in bridgmanite are clearly divided into two groups (from La to Gd and from Gd to Lu). Interphase REE partition coefficients in solid-state reactions were calculated at 21.5 and 24 GPa for the first time. The new data are applicable for interpretation of the trace-element composition of the lower mantle inclusions in natural diamonds from kimberlite; the experimentally determined effect of pressure on the interphase (bridgmanite/CaSiO3-perovskite) REE partition coefficients can be a potential qualitative geobarometer for mineral inclusions in super-deep diamonds.
DS202102-0202
2021
Hirata, T.Litasov, K.D., Kagi, H., Bekker, T.B., Makino, Y., Hirata, T., Brazhkin, V.V.Why Tolbachik diamonds cannot be natural.The American Mineralogist, Vol. 106. pp. 44-53. pdfRussiadeposit - Kamchatka

Abstract: Taking into account recent publications, we provide additional comprehensive evidence that type Ib cuboctahedral diamonds and some other microcrystalline diamonds from Kamchatka volcanic rocks and alluvial placers cannot be natural and undoubtedly represent synthetic materials, which appear in the natural rocks by anthropogenic contamination. The major arguments provided in favor of the natural origin of those diamonds can be easily disproved. They include the coexistence of diamond and deltalumite from Koryaksky volcano; coexistence with super-reduced corundum and moissanite, Mn-Ni silicide inclusions, F-Cl enrichment and F/Cl ratios, and carbon and nitrogen isotopes in Tolbachik diamonds, as well as microtwinning, Mn-Ni silicides, and other inclusions in microcrystalline diamond aggregates from other Kamchatka placers. We emphasize the importance of careful comparison of unusual minerals found in nature, which include type Ib cuboctahedral diamonds and super-reduced phase assemblages resembling industrial slags, with synthetic analogs. The cavitation model proposed for the origin of Tolbachik diamonds is also unreliable since cavitation has only been shown to cause the formation of nanosized diamonds only.
DS202108-1296
2029
Hirata, T.Litasov, K.D., Kagi, H., Bekker, T.B., Hirata, T., Makino, Y.Cuboctahedral type lb diamonds in ophiolitic chromitites and peridotites: the evidence for anthropogenic contamination.International Journal of High Pressure Research, Vol. 39, 3, pp. 480-488.Mantlediamond morphology

Abstract: Here we present trace element compositions of synthetic diamonds, which show spectacular similarity with the compositions of metallic inclusions in type Ib cuboctahedral diamonds in ophiolitic chromitites and peridotites. The compositions of inclusions in synthetic and ophiolite diamonds closely correspond to Ni:Mn:Co?=?70:25:5 in wt.%, which is the most widely used catalyst for HPHT growth of synthetic diamonds in China. Thus, we claim for thorough reconsideration of diamonds in ophiolitic rocks and emphasize that most of them appear by anthropogenic contamination.
DS1993-0675
1993
Hirayama, Y.Hirayama, Y., ujii, T.The melting relation system, iron and carbon at high pressure and its bearing on the early stage of the earth.Geophysical Research Letters, Vol. 20, No. 19, October 8, pp. 2095-2098.MantleCarbon
DS200512-0435
2005
Hird, J.Hird, J.Polishing under the microscope.Rough Diamond Review, No. 8, March pp. 40-41.Technology
DS200712-0440
2007
Hird, J.R.Hird, J.R., Bloomfield, M., Hayward, I.P.Investigating the mechanisms of diamond polishing using Raman spectroscopy.Philosophical Magazine, Vol. 87, 2, Jan. 11, pp. 267-280.TechnologyDiamond polishing
DS1992-1525
1992
Hirdes, W.Taylor, P.N., Moorbath, S., Leube, A., Hirdes, W.Early Proterozoic crustal evolution in the Birimian of Ghana: constraints from geochronology and isotope geochemistryPrecambrian Research, Vol. 56, No. 1/2, April pp. 97-112GhanaProterozoic, Geochronology
DS1996-0633
1996
Hirdes, W.Hirdes, W., Davis, D.W., Ludtke, G., Konan, G.Two generations of Birimian (Paleoproterozoic) volcanic belts in northeast Coted'Ivoire: Birimian controversyPrcambrian Research, Vol. 80, pp. 173-191GlobalGeochronology, Birimian volcanics
DS201412-0058
2014
Hirdes, W.Boger, S.D., Hirdes, W., Ferreira, C.A.M., Jenett, T., Dallwig, R., Fanning, C.M.The 580-520 Ma Gondwana suture of Madagascar and its continuation into Antarctica and Africa.Gondwana Research, in press available 14p.Africa, MadagascarShield - Arabian Nubian
DS201509-0385
2015
Hirdes, W.Boger, S.D., Hirdes, W., Ferreira, C.A.M., Jenett, T., Dallwig, R., Fanning, C.M.The 580-520 Ma Gondwana suture of Madagascar and its continuation into Antarctica and Africa.Gondwana Research, Vol. 28, pp. 1048-1060.Africa, MadagascarTectonics

Abstract: U-Pb age data from southwest Madagascar provide a compelling case that the pre-Gondwana Indian plate was stitched with the arc terranes of the Arabian Nubian Shield along a suture that closed between 580 Ma and 520 Ma. The key observations supportive of this interpretation are: (1) metamorphism dated to 630-600 Ma is manifested only on the west side of the suture in rocks that have affinities with the oceanic and island arc terranes of the Arabian Nubian Shield, or which represent continental rocks welded to these terranes prior to the amalgamation of Gondwana, and (2) orogenesis at 580-520 Ma is manifest in rocks on both sides of the suture, an observation taken to mark the timing of collision and to reflect spatial continuity across the suture. In southwest Madagascar the distribution of metamorphic ages places the suture along the Beraketa high-strain zone, the tectonic boundary between the Androyen and Anosyen domains. Similar age relationships allow for the extrapolation of this tectonic boundary into both East Antarctica and Africa.
DS201905-1017
2019
Hirdes, W.Boger, S.D., Maas, R., Pastuhov, M., Macey, P.H., Hirdes, W., Schulte, B., Fanning, C.M., Ferreira, C.A.M., Jenett, T., Dallwig, R.The tectonic domains of southern and western Madagascar.Precambrian Research, Vol. 327, pp. 144-175.Africa, Madagascarplate tectonics

Abstract: Southern and western Madagascar is comprised of five tectonic provinces that, from northeast to southwest, are defined by the: (i) Ikalamavony, (ii) Anosyen, (iii) Androyen, (iv) Graphite and (v) Vohibory Domains. The Ikalamavony, Graphite and Vohibory Domains all have intermediate and felsic igneous protoliths of tonalite-trondhjemite-granodiorite-granite composition, with positive ?Nd, and low Sr and Pb isotopic ratios. All three domains are interpreted to be the products of intra-oceanic island arc magmatism. The protoliths of the Ikalamavony and Graphite Domains formed repectively between c. 1080-980?Ma and 1000-920?Ma, whereas those of the Vohibory Domain are younger and date to between c. 670-630?Ma. Different post-formation geologic histories tie the Vohibory-Graphite and Ikalamavony Domains to opposite sides of the pre-Gondwana Mozambique Ocean. By contrast, the Androyen and Anosyen Domains record long crustal histories. Intermediate to felsic igneous protoliths in the Androyen Domain are of Palaeoproterozoic age (c. 2200-1800?Ma), of tonalite-trondhjemite-granodiorite-granite composition, and show negative ?Nd, moderate to high 87Sr/86Sr and variable Pb isotopic compositions. The felsic igneous protoliths of the Anosyen Domain are of granitic composition and, when compared to felsic gneisses of the Androyen Domain, show consistently lower Sr/Y and markedly higher Sr and Pb isotope ratios. Like the Vohibory and Graphite Domains, the Androyen Domain can be linked to the western side of the Mozambique Ocean, while the Anosyen Domain shares magmatic and detrital zircon commonalities with the Ikalamavony Domain. It is consequently linked to the opposing eastern side of this ocean. The first common event observed in all domains dates to c. 580-520?Ma and marks the closure of the Mozambique Ocean. The trace of this suture lies along the boundary between the Androyen and Anosyen Domains and is defined by the Beraketa high-strain zone.
DS201112-0916
2011
Hiroi, Y.Satish-Kumar, M., So, H., Yoshino, T., Kato, M., Hiroi, Y.Experimental determination of carbon isotope fractionation between iron carbide melt and carbon: 12 C-enriched carbon in the Earth's core?Earth and Planetary Science Letters, Vol. 310, 3-4, pp. 340-348.MantleCarbon
DS200412-0881
2003
Hiropse, K.Isshiki, E., Irifune, T., Hiropse, K., Ono, S., Ohishi, Y., Watanuki, T., Nishibori, E., Takat, M., Sakata, M.Stability of magnesite and its high pressure form in the lowermost mantle.Nature, No. 6969, pp. 60-62.MantleUHP
DS2001-0783
2001
HiroseMiyajima, N., Yagi, Hirose, Kondo, Fujino, MiuraPotential host phase of aluminum and potassium in the Earth's lower mantleAmerican Mineralogist, Vol. 86, pp. 740-46.MantleAlkali earth elements
DS200612-0586
2006
Hirose, H.Hirose, H., Karato, S., Comier, V., Brodholt, J., Yuen, D.Unsolved problems in the lowermost mantle.Geochimica et Cosmochimica Acta, Vol. 70, 18, p. 253. abstract only.MantleGeochemistry
DS1992-0712
1992
Hirose, K.Hirose, K., Kushiro, I.Partial melting of dry peridotites at high pressure determination of compositions of melts segregated from peridotite using aggregates of diamondEos, Transactions, Annual Fall Meeting Abstracts, Vol. 73, No. 43, October 27, abstracts p. 615GlobalPeridotite, Diamond aggregates
DS1993-0676
1993
Hirose, K.Hirose, K., Kushiro, I.Partial melting of dry peridotites at high pressures: determination of compositions of melts segregated from peridotite using aggregates of diamondEarth and Planetary Science Letters, Vol. 114, pp. 477-489MantlePeridotites, Experimental petrology
DS1997-0507
1997
Hirose, K.Hirose, K.Melting experiments on lherzolite KLB-1 under hydrous conditions generation high magnesian andesitic meltsGeology, Vol. 25, No. 1, Jan. pp. 42-44MantlePetrology - experimental, Andesitic melts
DS2001-0479
2001
Hirose, K.Hirose, K., Fei, Y., Funakoshi, K.I.In situ measurements of the phase transistion boundary ...Mg3Al2Si3O12: implications for nature seismic...Earth and Planetary Science Letters, Vol. 184, No.3-4, Jan.30, pp.567-74.MantleGeophysics - seismic, Discontinuities
DS2001-0480
2001
Hirose, K.Hirose, K., Kombayashi, T., Murakami, M., Funakoshi, K.In situ measurements of the majorite akimotoite perovskite phase transition boundaries in MgSiO3.Geophysical Research Letters, Vol. 28, No. 23, Dec. pp. 4351-4.MantlePerovskite
DS2001-0683
2001
Hirose, K.Li, J., Fei, Y., Mao, H.K., Hirose, K., Shieh, S.R.Sulfur in the Earth's coreEarth and Planetary Science Letters, Vol. 193, No. 3-4, pp.509-14.MantleSulphur, Geochemistry
DS2001-1066
2001
Hirose, K.Shimizu, K., Komiya, T., Hirose, K., Shimizu, Maruyamachromium spinel an excellent micro container for retaining primitive melts - implications for a hydrous plume ...Earth and Planetary Science Letters, Vol. 189, No. 3-4, July 15, pp. 177-88.Zimbabwe, MantleKomatiites, Melting - Belingwe Greenstone belt
DS2002-0720
2002
Hirose, K.Hirose, K.Phase transitions in pyrolitic mantle around 670 - km depth: implications for upwelling of plumes from the lower mantle.Journal of Geophysical Research, Vol. 107, 4, ECV-3 ( approx. 15 p.)MantleGeophysics - seismics, Core Mantle boundary
DS2002-0721
2002
Hirose, K.Hirose, K.The role of phase transitions in dynamics of the Earth's interiors18th. International Mineralogical Association Sept. 1-6, Edinburgh, abstract p.75,6.MantleUHP mineralogy, Boundary - core mantle
DS2002-1113
2002
Hirose, K.Murakami, M., Hirose, K., Yurimoto, Nakashima, TakafujiWater in Earth's lower mantleScience, No. 5561, Mar. 8, pp. 1885-6.MantleWater
DS200412-0834
2004
Hirose, K.Hirose, K., Shimizu, N., Van Westrenen, W., Fei, Y.Trace element partitioning in the Earth's lower mantle and implications for geochemical consequences of partial melting at the cPhysics of the Earth and Planetary Interiors, Vol. 146, 1-2, pp. 249-260.MantleGeochemistry
DS200412-0882
2004
Hirose, K.Itaka, T., Hirose, K., Kawamura, K., Murakami, M.The elasticity of the MgSiO3 post perovskite phase in the Earth's lowermost mantle.Nature, No. 6998, July 22, pp. 442-444.MantlePerovskite
DS200412-0960
2003
Hirose, K.Katayama, I., Hirose, K., Yurimoto, H., Nakashima, S.Water solubility in majoritic garnet in subducting oceanic crust.Geophysical Research Letters, Vol. 22, SDE 2 Nov. 15, 10.1029/2003 GLO18127MantleGeochemistry - subduction
DS200412-1381
2004
Hirose, K.Murakami, M., Hirose, K., Kawamura, K., Sata, N., Ohishi, Y.Phase transition of MgSiO3 perovskite in the deep lower mantle.Lithos, ABSTRACTS only, Vol. 73, p. S78. abstractMantleSeismic discontinuity
DS200412-1961
2004
Hirose, K.Takafuji, N., Hirose, K., Ono, S., Xu, F., Mitome, M., Bando, Y.Segregation of core melts by permeable flow in the lower mantle.Earth and Planetary Science Letters, Vol. 224, 3-4, pp. 249-257.MantleGeothermometry - boundary
DS200512-0436
2005
Hirose, K.Hirose, K., Takafuji, N., Sata, N., Ohishi, Y.Phase transition and density of subducted MORB crust in the lower mantle.Earth and Planetary Science Letters, Vol. 237, 1-2, Aug, 30, pp. 239-251.MantleMineral chemistry, subduction
DS200612-0587
2006
Hirose, K.Hirose, K.Post perovskite phase transition and its geophysical implications.Reviews of Geophysics, Vol. 44, 3, RG3001.MantleGeophysics
DS200712-0441
2007
Hirose, K.Hirose, K., Kawamura, K.Discovery of post-perovskite phase transition and implications for the nature of 'D' layer of the mantle.Ohtani: Advances in high pressure mineralogy, pp. 37-46.MantleMineralogy
DS200712-0763
2007
Hirose, K.Murkami, M., Sinogeikin, S.V., Bass, J.D., Sata, N., Ohishi, Y., Hirose, K.Sound velocity of MgSiO3 post perovskite phase: a constraint on the D' discontinuity.Earth and Planetary Science Letters, Vol. 259, 1-2, July 15, pp. 18-23.MantleDiscontinuity
DS200812-0472
2007
Hirose, K.Hirose, K., Brodholt, J., Lay, T., Yuen, D.A.An introduction to post-perovskite: the last mantle phase transition.AGU American Geophysical Union Monograph, No. 174, pp. 1-8.MantlePerovskite
DS200812-0473
2008
Hirose, K.Hirose, K., Lay, T.Discovery of post perovskite and new views on the core mantle boundary region.Elements, Vol. 4, 3, June pp. 183-189.MantleBoundary
DS200812-0474
2008
Hirose, K.Hirose, K., Takafur, N., Fujino, K., Shieh, S.R., Duffy, T.S.Iron partitioning between perovskite and post peroovskite: a transmission electron microscope study.American Mineralogist, Vol. 93, pp. 1678-1681.MantlePhase transition
DS200812-0817
2008
Hirose, K.Ohta, K., Hirose, K., Lay, T., Sata, N., Ohishi, Y.Phase transitions in pyrolite and MORB at lowermost mantle conditions: implications for a MORB rich pile above the core-mantle boundary.Earth and Planetary Science Letters, Vol. 267, 1-2, pp.107-117.MantlePetrology
DS200912-0523
2009
Hirose, K.Murakami, M., Oshishi, Y., Hirao, N., Hirose, K.Elasticity of MgO to 130 GPa: implications for lower mantle mineralogy.Earth and Planetary Science Letters, Vol. 277, 1-2, pp. 123-129.MantleMineralogy
DS201012-0280
2010
Hirose, K.Hirose, K.Perovskite and post-perovskite in Earth's lower mantle.International Mineralogical Association meeting August Budapest, AbstractMantlePerovskite
DS201112-0969
2011
Hirose, K.Sinmyo, R., Hirose, K., Muto, S., Ohishi, Y., Yasuhara, A.The valence state and partitioning of iron in the Earth's lowermost mantle.Journal of Geophysical Research, Vol. 116, B7, B07205.MantleChemistry
DS201212-0300
2013
Hirose, K.Hirose, K.Composition and state of the core.Annual Review of Earth and Planetary Sciences, Vol. 41, available April 2013MantleBoundary
DS201212-0385
2012
Hirose, K.Kudo, Y., Hirose, K.,Murakami, M., Asahara, Y., Ozawa, H., Ohishi, Y., Hirao, N.Sound velocity measurements of CaSiO3 perovskite to 133 Gpa an implications for lowermost mantle seismic anomalies.Earth and Planetary Science Letters, Vol. 349-350 pp. 1-7.MantlePerovskite
DS201212-0503
2012
Hirose, K.Murakami, M., Ohishi, Y., Hirao, N., Hirose, K.A perovskite lower mantle inferred from high pressure, high temperature sound velocity data.Journal of the Geological Society of India, Vol. 80, 1, p. 147. Brief reviewMantlePerovskite
DS201212-0504
2012
Hirose, K.Murakami, M., Ohishi, Y., Hirao, N., Hirose, K.A perovskite lower mantle inferred from high pressure, high temperature sound velocity data.Nature, Vol. 485, May 3, pp. 90-94.MantlePerovskite
DS201312-0388
2013
Hirose, K.Hirose, K., Labrosse, S., Hernlund, J.Composition and state of the core.Annual Review of Earth and Planetary Sciences, Vol. 41, pp. 657-691.MantleMineralogy
DS201312-0389
2013
Hirose, K.Hirose, K., Tateno, S., Ozawa, H.Petrological evidence for deep lower mantle melting.Goldschmidt 2013, AbstractMantleUHP
DS201312-0462
2013
Hirose, K.Kato, C., Hirose, K., Kombayashi, T., Ozawa, H., Ohisi, Y.NAL phase in K rich portions of the lower Mantle.Geophysical Research Letters, Vol. 40, 19, pp. 5085-5088.MantleAlkalic
DS201312-0656
2013
Hirose, K.Noguchi, M., Komabayashi, T., Hirose, K., Ohishi, Y.High-temperature compression experiments of CaSiO3 perovskite to lowermost mantle conditions and its thermal equation of state.Physics and Chemistry of Minerals, Vol. 40, pp. 81-91.MantleGeothermometry
DS201312-0828
2013
Hirose, K.Sinmyo, R., Hirose, K.Iron partitioning in pyrolitic lower mantle.Physics and Chemistry of Minerals, Vol. 40, 2, pp. 107-113.MantlePerovskite, mineral chemistry
DS201412-0359
2014
Hirose, K.Hirose, K.Deep earth mineralogy revealed by ultrahigh pressure experiments.Mineralogical Magazine, Vol. 78, 2, pp. 437-446.MantleUHP
DS201412-0360
2014
Hirose, K.Hirose, K., McDonough, B., McNamara, A.Chemical composition of Earth's mantle.Goldschmidt Conference 2014, 1p. AbstractMantleMineral chemistry
DS201412-0403
2014
Hirose, K.Imada, S., Ohta, K., Yagi, T., Hirose, K., Yoshida, H., Nagahara, H.Measurements of lattice thermal conductivity of MgO to core-mantle boundary.Geophysical Research Letters, Vol. 41, 13, pp. 4542-4547.MantleGeothermometry
DS201412-0922
2013
Hirose, K.Tatsumi, Y., Suzuki, T., Ozawa, H., Hirose, K., Hanyu, T., Ohishi, Y.Accumulation of 'anti-continent' at the base of the mantle and its recycling in mantle plumes.Geochimica et Cosmochimica Acta, in press availableMantleD layer
DS201504-0225
2015
Hirose, K.Tateno, S., Kuwayama, Y., Hirose, K., Ohishi, Y.The structure of Fe-Si alloy in Earth's inner core.Earth and Planetary Science Letters, Vol. 418, pp. 11-18.MantleCore
DS201601-0034
2015
Hirose, K.Nakajima, Y., Imada, S., Hirose, K., Komabayashi, T., Ozawa, H., Tateno, S., Tsutsui, S., Kuwayama, Y., Baron, A.Q.R.Carbon depleated outer core revealed by sound velocity measurements of liquid iron-carbon alloy.Nature Communications, 10.1038/ NCOMMS9942MantleCarbon

Abstract: The relative abundance of light elements in the Earth’s core has long been controversial. Recently, the presence of carbon in the core has been emphasized, because the density and sound velocities of the inner core may be consistent with solid Fe7C3. Here we report the longitudinal wave velocity of liquid Fe84C16 up to 70?GPa based on inelastic X-ray scattering measurements. We find the velocity to be substantially slower than that of solid iron and Fe3C and to be faster than that of liquid iron. The thermodynamic equation of state for liquid Fe84C16 is also obtained from the velocity data combined with previous density measurements at 1 bar. The longitudinal velocity of the outer core, about 4% faster than that of liquid iron, is consistent with the presence of 4-5 at.% carbon. However, that amount of carbon is too small to account for the outer core density deficit, suggesting that carbon cannot be a predominant light element in the core.
DS201704-0620
2017
Hirose, K.Ballmer, M.D., Houser, C., Hernlund, J.W., Wentzcovitch, R.M., Hirose, K.Persistence of strong silica enriched domains in the Earth's lower mantle.Nature Geoscience, Vol. 10, 3, pp. 236-240.MantleGeophysics - seismic

Abstract: The composition of the lower mantle—comprising 56% of Earth’s volume—remains poorly constrained. Among the major elements, Mg/Si ratios ranging from ~0.9-1.1, such as in rocky Solar-System building blocks (or chondrites), to ~1.2-1.3, such as in upper-mantle rocks (or pyrolite), have been proposed. Geophysical evidence for subducted lithosphere deep in the mantle has been interpreted in terms of efficient mixing, and thus homogenous Mg/Si across most of the mantle. However, previous models did not consider the effects of variable Mg/Si on the viscosity and mixing efficiency of lower-mantle rocks. Here, we use geodynamic models to show that large-scale heterogeneity associated with a 20-fold change in viscosity, such as due to the dominance of intrinsically strong (Mg, Fe)SiO3-bridgmanite in low-Mg/Si domains, is sufficient to prevent efficient mantle mixing, even on large scales. Models predict that intrinsically strong domains stabilize mantle convection patterns, and coherently persist at depths of about 1,000-2,200?km up to the present-day, separated by relatively narrow up-/downwelling conduits of pyrolitic material. The stable manifestation of such bridgmanite-enriched ancient mantle structures (BEAMS) may reconcile the geographical fixity of deep-rooted mantle upwelling centres, and geophysical changes in seismic-tomography patterns, radial viscosity, rising plumes and sinking slabs near 1,000?km depth. Moreover, these ancient structures may provide a reservoir to host primordial geochemical signatures.
DS201704-0643
2017
Hirose, K.Ohta, K., Yagi, T., Hirose, K., Ohishi, Y.Thermal conductivity of ferropericlase in the Earths's lower mantle.Earth and Planetary Science Letters, Vol. 465, pp. 29-37.MantleGeothermometry

Abstract: (Mg,?Fe)O ferropericlase (Fp) is one of the important minerals comprising Earth's lower mantle, and its thermal conductivity could be strongly influenced by the iron content and its spin state. We examined the lattice thermal conductivity of (Mg,?Fe)O Fp containing 19 mol% iron up to 111 GPa and 300 K by means of the pulsed light heating thermoreflectance technique in a diamond anvil cell. We confirmed a strong reduction in the lattice thermal conductivity of Fp due to iron substitution as reported in previous studies. Our results also show that iron spin crossover in Fp reduces its lattice thermal conductivity as well as its radiative conduction. We also measured the electrical conductivity of an identical Fp sample up to 140 GPa and 2730 K, and found that Fp remained an insulator throughout the experimental conditions, indicating the electronic thermal conduction in Fp is negligible. Because of the effects of strong iron impurity scattering and spin crossover, the total thermal conductivity of Fp at the core-mantle boundary conditions is much smaller than that of bridgmanite (Bdg). Our findings indicate that Bdg (and post-perovskite) is the best heat conductor in the Earth's lower mantle, and distribution of iron and its valence state among the lower mantle minerals are key factors to control the lower mantle thermal conductivity.
DS201902-0258
2018
Hirose, K.Badro, J., Aubert, J., Hirose, K., Nomura, R., Blanchard, I., Borensztajn, S., Siebert, J.Magnesium partitioning between Earth's mantle and core and its potential to drive an early exsolution geodynamo.Geophysical Research Letters, Vol. 45, 24, pp. 13,240-13,248.Mantlegeodynamics

Abstract: We measure the incorporation of magnesium oxide (one of the main components of Earth's mantle) into iron (the main constituent Earth's core), using extremely high pressure and temperature experiments that mimic the conditions of Earth's mantle and core. We find that magnesium oxide dissolution depends on temperature but not on pressure, and on metal (i.e., core) composition but not silicate (i.e., mantle) composition. Our findings support the idea that magnesium oxide dissolved in the core during its formation will precipitate out during subsequent core cooling. The precipitation should stir the entire core to produce a magnetic field in Earth's distant past, at least as intense as the present?day field.
DS201912-2808
2019
Hirose, K.Oka, K., Hirose, K., Tagawa, S., Kidokoro, Y., Nakajima, Y., Kuwayama, Y., Morard, G., Coudurier, N., Fiquet, G.Melting in the Fe-FeO system to 204 GPa: implications for oxygen in Earth's core.American Mineralogist, Vol. 104, pp. 1603-1607.Mantlemelting

Abstract: We performed melting experiments on Fe-O alloys up to 204 GPa and 3500 K in a diamond-anvil cell (DAC) and determined the liquidus phase relations in the Fe-FeO system based on textural and chemical characterizations of recovered samples. Liquid-liquid immiscibility was observed up to 29 GPa. Oxygen concentration in eutectic liquid increased from >8 wt% O at 44 GPa to 13 wt% at 204 GPa and is extrapolated to be about 15 wt% at the inner core boundary (ICB) conditions. These results support O-rich liquid core, although oxygen cannot be a single core light element. We estimated the range of possible liquid core compositions in Fe-O-Si-C-S and found that the upper bounds for silicon and carbon concentrations are constrained by the crystallization of dense inner core at the ICB.
DS202009-1649
2020
Hirose, K.Okuda, Y., Ohta, K., Haseawa, A., Yagi, T., Hirose, K., Kawaguchi, S.I., Ohishi, Y.Thermal conductivity of Fe bearing post- perovskite in the Earth's lowermost mantle.Earth and Planetary Science Letters, Vol. 547, 9p. PdfMantleperovskite

Abstract: The thermal conductivity of post-perovskite (ppv), the highest-pressure polymorph of MgSiO3 in the Earth's mantle, is one of the most important transport properties for providing better constraints on the temperature profile and dynamics at the core-mantle boundary (CMB). Incorporation of Fe into ppv can affect its conductivity, which has never been experimentally investigated. Here we determined the lattice thermal conductivities of ppv containing 3 mol% and 10 mol% of Fe at high P-T conditions - of pressures up to 149 GPa and 177 GPa, respectively, and temperatures up to 1560 K - by means of the recently developed pulsed light heating thermoreflectance technique combining continuous wave heating lasers. We found that the incorporation of Fe into ppv moderately reduces its lattice thermal conductivity as it increases the Fe content. The bulk conductivity of ppv dominant pyrolite is estimated as 1.5 times higher than that of pyrolite consisting of bridgmanite and ferropericlase in the lower mantle, which agrees with the traditional view that ppv acts as a better heat conductor than bridgmanite in the Earth's lowermost mantle.
DS202106-0973
2021
Hirose, K.Tagawa, S., Sakamoto, N., Hirose, K., Hernlund, J., Ohishi, Y., Yurimoto, H.Experimental evidence for more hydrogen in Earth's core than in the oceans.Nature Communications, doi.org/10.1038/s41467-021-22035-0 Vol. 12 8p. PdfMantlehydrogen

Abstract: Hydrogen is one of the possible alloying elements in the Earth’s core, but its siderophile (iron-loving) nature is debated. Here we experimentally examined the partitioning of hydrogen between molten iron and silicate melt at 30-60 gigapascals and 3100-4600?kelvin. We find that hydrogen has a metal/silicate partition coefficient DH???29 and is therefore strongly siderophile at conditions of core formation. Unless water was delivered only in the final stage of accretion, core formation scenarios suggest that 0.3-0.6?wt% H was incorporated into the core, leaving a relatively small residual H2O concentration in silicates. This amount of H explains 30-60% of the density deficit and sound velocity excess of the outer core relative to pure iron. Our results also suggest that hydrogen may be an important constituent in the metallic cores of any terrestrial planet or moon having a mass in excess of ~10% of the Earth.
DS201412-0451
2014
Hirose, T.Kendrick, J.E., Lavallee, Y., Hirose, T., Di Toro,G., Hornby, A.J., De Angelis, S., Dingwell, D.B.Volcanic drumbeat seismicity caused by stick-slip motion and magmatic fictional melting.Nature Geoscience, Vol. 7, pp. 438-442.MantleMagmatism
DS2002-0722
2002
Hirosi, K.Hirosi, K.Phase transitions in pyrolitic mantle around 670 Km depth: implications for upwelling plumes lower mantleJournal of Geophysical Research, Vol. No.B, April 27, pp., Vol. No.B, April 27, pp.MantlePlumes Boundary
DS2002-0723
2002
Hirosi, K.Hirosi, K.Phase transitions in pyrolitic mantle around 670 Km depth: implications for upwelling plumes lower mantleJournal of Geophysical Research, Vol. No.B, April 27, pp., Vol. No.B, April 27, pp.MantlePlumes Boundary
DS201602-0212
2015
Hirsch, A.C.Hirsch, A.C., Dalton, C.A., Ritsema, J.Constraints on shear velocity in the cratonic upper mantle from Rayleigh wave phase velocity.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 11, Nov. pp. 3982-4005.MantleGeophysics - seismic

Abstract: Seismic models provide constraints on the thermal and chemical properties of the cratonic upper mantle. Depth profiles of shear velocity from global and regional studies contain positive velocity gradients in the uppermost mantle and often lack a low-velocity zone, features that are difficult to reconcile with the temperature structures inferred from surface heat flow data and mantle-xenolith thermobarometry. Furthermore, the magnitude and shape of the velocity profiles vary between different studies, impacting the inferences drawn about mantle temperature and composition. In this study, forward modeling is used to identify the suite of one-dimensional shear-velocity profiles that are consistent with phase-velocity observations made for Rayleigh waves traversing Precambrian cratons. Two approaches to the generation of 1-D models are considered. First, depth profiles of shear velocity are predicted from thermal models of the cratonic upper mantle that correspond to a range of assumed values of mantle potential temperature, surface heat flow, and radiogenic heat production in the lithosphere. Second, shear velocity-depth profiles are randomly generated. In both cases, Rayleigh wave phase velocity is calculated from the Earth models, and acceptable models are identified on the basis of comparison to observed phase velocity. The results show that it is difficult but not impossible to find acceptable Earth models that contain a low-velocity zone in the upper mantle and that temperature structures that are consistent with constraints from mantle xenoliths yield phase-velocity predictions lower than observed. For most acceptable randomly generated Earth models, shear velocity merges with the global average at approximately 300 km.
DS201603-0385
2016
Hirsch, A.C.Hirsch, A.C., Dalton, C.A., Ritsema, J.Constraints on shear velocity in the cratonic upper mantle from Rayleigh wave phase velocity.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 11, pp.MantleGeophysics - seismics
DS1986-0364
1986
Hirsch, F.Hirsch, F.Platelets, dislocation loops and voidites in diamondProceedings of the Royal Society of London, ser. A., Vol. 407, No. 1833, pp. 239-258GlobalDiamond, diamond morphology, Crystallography
DS200812-0475
2007
Hirsch, K.K.Hirsch, K.K., Scheck-Wenderoth, M., Paton, D.A., Bauer, K.Crustal structure beneath the Orange Basin, South Africa.South African Journal of Geology, Vol. 110, 2-3, Sept. pp. 249-260.Africa, South AfricaTectonics
DS1986-0365
1986
Hirsch, L.M.Hirsch, L.M., Wang, C.Y.Electrical conductivity of olivine during high temperature creepJournal of Geophysical Research, Vol. 91, No. B10, September, pp. 10, 429-10, 441GlobalUpper mantle, diamond
DS1990-0702
1990
Hirsch, L.M.Hirsch, L.M.Enhancing mantle conductivityNature, Vol. 347, No. 6290, September 20, p. 232GlobalMantle-basalts, Geophysics
DS1986-0366
1986
Hirsch, P.B.Hirsch, P.B., Hutchinson, J.L., Titchmar, J.Voidites in diamond- evidence for a crystalline phase containing nitrogenPhilosophical Magazine, Section A, Vol. 54, No. 2, August pp. L49-L54 ( letterGlobalDiamond morphology
DS1998-0053
1998
HirschmannAsmeron, Y., Cheng, Edwards, Thomas, Hirschmann231 Pa 235 U constraints on mantle meltingMineralogical Magazine, Goldschmidt abstract, Vol. 62A, p. 81-2.MantleGeodynamics, Alkali basalts
DS200712-0204
2007
HirschmannCourtier, A.M., Jackson, Lawrence, Wang, Lee, Halama, Warren, Workman, Xu, Hirschmann, Larson, Hart, Lithgo-Bertelloni, Stixrude, ChenCorrelation of seismic and petrologic thermometers suggests deep thermal anomalies beneath hotspots.Earth and Planetary Science Letters, Vol. 264, 1-2, pp. 308-316.MantleGeothermometry
DS200612-0080
2006
Hirschmann, M.Ballentine, C., Asimov, P., Hirschmann, M., Marty, B.Volatiles in the mantle.Goldschmidt Conference 16th. Annual, S4-07 theme abstract 1/8p. goldschmidt2006.orgMantleGeochemistry
DS200612-0588
2006
Hirschmann, M.Hirschmann, M.Earth Science: a wet mantle conductor?Nature, Vol. 439, 7075, p. E3.MantleHydrous melting
DS200812-1258
2008
Hirschmann, M.Withers, A., Hirschmann, M.Influence of temperature, composition, silica avtivity and oxygen fugacity on the H2O storage capacity of olivine at 8 GPA.Contributions to Mineralogy and Petrology, Vol. 156, 4, pp.595-605.MantleOlivine
DS1992-0758
1992
Hirschmann, M.M.Irving, A.J., Hirschmann, M.M., Kuehner, S.M.Exsolution of chromite and diopside from mantle olivine: Montana dunitexenoliths and the Twin Sisters duniteEos Transactions, Vol. 73, No. 14, April 7, supplement abstracts p.336Montana, WashingtonMantle, Xenoliths
DS1994-0775
1994
Hirschmann, M.M.Hirschmann, M.M., Stolper, E.M.Can the garnet signature in Mid Ocean Ridge Basalt (MORB) be derived from garnet pyroxenites in Mid Ocean Ridge Basalt (Mid Ocean Ridge Basalt (MORB))source regions?Geological Society of America (GSA) Abstract Volume, Vol. 26, No. 7, ABSTRACT only p. A38.MantleIgneous petrology, Garnet pyroxenites
DS1998-0622
1998
Hirschmann, M.M.Hirschmann, M.M., Baker, M.B., Stolper, E.M.The effect of alkalis on the silica content of mantle derived meltsGeochimica et Cosmochimica Acta, Vol. 62, No. 5, pp. 883-902.Mantlegeochemistry, Alkali - silica
DS1998-0623
1998
Hirschmann, M.M.Hirschmann, M.M., Ghiorso, M.S., Stolper, E.M.Calculation of peridotite partial melting from thermodynamic models of minerals and melts. #1Journal of Petrology, Vol. 39, No. 6, June 1, pp. 1091-1116.GlobalMethodology, techniques, experiments
DS1999-0308
1999
Hirschmann, M.M.Hirschmann, M.M., Asimow, P.D., Stolper, E.M.Calculation of peridotite partial melting from thermodynamic models of minerals and melts. II isobaricJournal of Petrology, Vol. 40, No. 5, May, pp. 831-51.GlobalMelting - production, source
DS1999-0309
1999
Hirschmann, M.M.Hirschmann, M.M., Ghiorso, M.S., Stopler, E.M.Calculation of peridotite partial melting from thermodynamic models of minerals and melts. III.Journal of Petrology, Vol. 40, No. 2, Feb. 1, pp. 297-314.MantleMelting - source composition
DS2001-0619
2001
Hirschmann, M.M.Kogiso, T., Hirschmann, M.M.Experimental study of clinopyroxenite partial melting and the origin of ultra calcic melt inclusions.Contributions to Mineralogy and Petrology, Vol. 142, No. 3, Dec. pp. 347-60.GlobalPetrology
DS2001-0620
2001
Hirschmann, M.M.Kogiso, T., Hirschmann, M.M.Experimental study of clinopyroxenite partial melting and the origin of ultra calcite melt inclusions.Contributions to Mineralogy and Petrology, Vol. 142, pp. 347-60.GlobalPetrology - melt inclusions
DS2001-1269
2001
Hirschmann, M.M.Xirouchakis, D., Hirschmann, M.M., Simpson, J.A.The effect of titanium on the silica content and on mineral liquid partitioning mantle equilibrated melts.Geochimica et Cosmochimica Acta, Vol. 65, No. 14, pp. 2201-2217.MantleMelting - not specific to kimberlites, Olivine, orthopyroxene saturated mafic
DS2002-1248
2002
Hirschmann, M.M.Pertermann, M., Hirschmann, M.M.Trace element partitioning between vacancy rich eclogitic clinopyroxene and silicate melt.American Mineralogist, Vol.87, pp. 1365-76.GlobalEclogites
DS2002-1249
2002
Hirschmann, M.M.Pertermann, M., Hirschmann, M.M.Trace element partioning between vacancy rich eclogitic clinopyroxene and silicate meltAmerican Mineralogist, Vol. 87, pp. 1365-76.MantleEclogites, Petrology - experimental
DS2003-0589
2003
Hirschmann, M.M.Hirschmann, M.M., Kogiso, T., Baker, M.B., Stolper, E.M.Alkalic magmas generated by partial melting of garnet pyroxeniteGeology, Vol. 31, 6, June pp. 481-4.GlobalBlank
DS2003-0590
2003
Hirschmann, M.M.Hirschmann, M.M., Kogiso, T., Baker, M.B., Stolper, M.Alkalic magmas generated by partial melting of garnet pyroxeniteGeology, Vol. 31, 6, June pp. 481-5.GlobalMagmatism
DS2003-1071
2003
Hirschmann, M.M.Petermann, M., Hirschmann, M.M.Anhydrous partial melting experiments on MORB like eclogite: phase relations, phaseJournal of Petrology, Vol. 44, 12, pp. 2173-2202.MantleMetasomatism - eclogite
DS200412-0407
2004
Hirschmann, M.M.das Gupta, R., Stalker, K., Withers, A.C., Hirschmann, M.M.The transition from carbonate rich to silicate rich melts in eclogite: partial melting experiments of carbonated eclogite at 3 GLithos, ABSTRACTS only, Vol. 73, p. S23. abstractTechnologyEclogite
DS200412-0408
2004
Hirschmann, M.M.Dasgupta, R., Hirschmann, M.M., Withers, A.C.Deep global cycling of carbon constrained by the solidus of anhydrous, carbonated eclogite under upper mantle conditions.Earth and Planetary Science Letters, Vol. 227, 1-2, Oct. 30, pp. 73-85.United States, HawaiiGarnet, pyroxene, carbonated, melting
DS200412-0835
2003
Hirschmann, M.M.Hirschmann, M.M., Kogiso, T., Baker, M.B., Stolper, E.M.Alkalic magmas generated by partial melting of garnet pyroxenite.Geology, Vol. 31, 6, June pp. 481-4.TechnologyAlkalic
DS200412-1534
2003
Hirschmann, M.M.Petermann, M., Hirschmann, M.M.Anhydrous partial melting experiments on MORB like eclogite: phase relations, phase compositions and mineral melt partitioning oJournal of Petrology, Vol. 44, 12, pp. 2173-2202.MantleMetasomatism - eclogite
DS200512-0209
2005
Hirschmann, M.M.Das Gupta, R., Hirschmann, M.M., Dellas, N.The effect of bulk composition on the solidus of carbonated eclogite from partial melting experiments at 3? GPAContributions to Mineralogy and Petrology, Vol. 149, 3, pp. 288-305.Eclogite, mineral chemistry
DS200512-0211
2005
Hirschmann, M.M.Dasgupta, R., Hirschmann, M.M., Dellas, N.The effect of bulk composition on the solidus of carbonated eclogite from partial melting experiments at 3 GPa.Contributions to Mineralogy and Petrology, Vol. 149, 3, May pp. 288-305.MantleExperimental petrology, eclogites, peridotites, carbonatites
DS200512-0437
2005
Hirschmann, M.M.Hirschmann, M.M., Aubaud, C., Withers, A.C.Storage capacity of H2O in nominally anhydrous minerals in the upper mantle.Earth and Planetary Science Letters, Advanced in press,MantleWadsleyite, peridotite, melting
DS200512-0555
2004
Hirschmann, M.M.Kogiso, T., Hirschmann, M.M., Pertermann, M.High pressure partial melting of mafic lithologies in the mantle.Journal of Petrology, Vol. 45, 12, Dec. pp. 2407-2422.MantleUHP
DS200612-0307
2006
Hirschmann, M.M.Das Gupta, R., Hirschmann, M.M.Melting in the Earth's deep upper mantle caused by carbon dioxide.Nature, Vol. 440, 7084, Mar. 30, pp. 659-662.MantleMelting
DS200612-0308
2006
Hirschmann, M.M.Das Gupta, R., Hirschmann, M.M., Stalker, K.Immiscible transition from carbonate rich to silicate rich melts in the 3 GPa melting interval of eclogite + CO2 and genesis of silica undersaturated Oceanic lavas.Journal of Petrology, Vol. 47, 4, April pp. 647-671.Mantle, Oceanic IslandCarbonatite, eclogites
DS200612-0589
2006
Hirschmann, M.M.Hirschmann, M.M.Water, melting, and the deep Earth H2O cycle.Annual Review of Earth and Planetary Sciences, Vol. 34, pp. 629-653.MantleHydrous melting, storage capacity, transition zone
DS200712-0215
2007
Hirschmann, M.M.Dasgupta, R., Hirschmann, M.M.Effect of variable carbonate concentration on the solidus of mantle peridotite.American Mineralogist, Vol. 92, 2, Feb-Mar. pp. 370-379.MantleCarbonatite
DS200712-0439
2007
Hirschmann, M.M.Hiraga, T., Hirschmann, M.M., Kohlstedt, D.L.Equilibrium interface segregation in the diopside forsterite system II: applications of interface enrichment to mantle geochemistry.Geochimica et Cosmochimica Acta, Vol. 71, 5, pp. 1281-1289.MantleGeochemistry
DS200712-0442
2007
Hirschmann, M.M.Hirschmann, M.M., Dasgupta, R.Carbonatite mantle interaction in the formation of highly alkalic oceanic island basalts.Plates, Plumes, and Paradigms, 1p. abstract p. A408.MantleMelting
DS200712-0560
2006
Hirschmann, M.M.Kogiso, T., Hirschmann, M.M.Partial melting experiments of bimineralic eclogite and the role of recycled mafic oceanic crust in the genesis of ocean island basalts.Geochimica et Cosmochimica Acta, In press availableMantleEclogite - experimental petrology
DS200712-0923
2007
Hirschmann, M.M.Sa Gupta, R., Hirschmann, M.M., Smith, N.D.Partial melting experiments of peridotite + CO2 at 3 GPa and genesis of alkalic Ocean Island basalts.Journal of Petrology, Vol. 48, 11, pp. 2093-2124.MantleMelting
DS200812-0476
2008
Hirschmann, M.M.Hirschmann, M.M., Tenner, T., Aubaud, C.Understanding dehydration melting of a nominally anhydrous mantle: the primacy of partitioning.Goldschmidt Conference 2008, Abstract p.A381.MantleMelting
DS200912-0153
2009
Hirschmann, M.M.Dasgupta, R., Hirschmann, M.M., McDonough, W.F., Spiegelman, M., Withers, A.C.Trace element partitioning between garnet lherzolite and carbonatite at 6.6 and 8.6 GPa with application to the geochemistry of the mantle and mantle derived meltsChemical Geology, Vol. 262, 1-2, May 15, pp. 57-77.MantleMelting
DS200912-0301
2009
Hirschmann, M.M.Hirschmann, M.M.Partial melts in the seismic low velocity zone.Goldschmidt Conference 2009, p. A534 Abstract.MantleMelting
DS200912-0302
2009
Hirschmann, M.M.Hirschmann, M.M., Dasgupta, R.The H/C ratios of Earth's near surface and deep reservoirs, and consequences for deep Earth volatile cycles.Chemical Geology, Vol. 262, 1-2, May 15, pp. 4-16.MantleGeochemistry
DS200912-0751
2009
Hirschmann, M.M.Tenner, T.J., Hirschmann, M.M., Withers, A.C., Herv, R.L.Hydrogen partitioning between nominally anhydrous upper mantle minerals and melt between 3 and 5 GPa and applications to hydrous peridotite partial melting.Chemical Geology, Vol. 262, 1-2, May 15, pp. 42-56.MantleMelting
DS201012-0134
2010
Hirschmann, M.M.Dagupta, R., Hirschmann, M.M.The deep carbon cycle and melting in Earth's interior.Earth and Planetary Science Letters, Vol. 298, 1-2, Sept. 15, pp. 1-13.MantleMelting
DS201112-0238
2011
Hirschmann, M.M.David, F.A., Hirschmann, M.M., Humayun, M.The composition of the incipient partial melt of garnet peridotite at 3 GPa and the origin of OIB.Earth and Planetary Science Letters, Vol. 308, 3-4, pp. 380-390.MantleMelting
DS201112-0248
2011
Hirschmann, M.M.Davis, F.A., Humayun, M., Hirschmann, M.M., Cooper, R.S.Partitioning of first row transition elements between peridotite and melt.Goldschmidt Conference 2011, abstract p.728.MantleMelting
DS201112-0434
2011
Hirschmann, M.M.Hirschmann, M.M.Deep Earth volatile cycles: from ancient to modern.Goldschmidt Conference 2011, abstract p.1028.MantleReservoirs of H and C, plate tectonics
DS201212-0020
2012
Hirschmann, M.M.Ardia, P., Hirschmann, M.M., Withers, A.C., Tenner, T.J.H2O storage capacity of olivine at 5-8 Gpa and consequences for dehydration partial melting of the upper mantle.Earth and Planetary Science Letters, Vol. 345-348, pp. 104-116.MantleMelting
DS201212-0725
2012
Hirschmann, M.M.Tenner, T.J., Hirschmann, M.M., Withers, A.C., Paola, A.H2O storage capacity of olivine and low-Ca pyroxene from 10 to 13 Gpa: consequences for dehydration melting above the transition zone.Contributions to Mineralogy and Petrology, Vol. 163, 2, pp. 297-316.MantleMelting
DS201312-0186
2013
Hirschmann, M.M.Dasgupta, R., Mallik, A., Tsuno, K., Withers, A.C., Hirth, G., Hirschmann, M.M.Carbon dioxide rich silicate melt in the Earth's upper mantle.Nature, Vol. 493, Jan. 10, pp. 211-215.MantleMelting
DS201312-0193
2013
Hirschmann, M.M.Davis, F.A., Hirschmann, M.M.The effects of K2O on the compositions of near solidus melts of garnet peridotite at 3 Gpa and the origin of basalts from enriched mantle.Contributions to Mineralogy and Petrology, Vol. 166, 4, pp. 1029-1046.MantleSubduction - oceanic
DS201312-0390
2013
Hirschmann, M.M.Hirschmann, M.M.Crystal structure in Earth's inner core.Goldschmidt 2013, AbstractMantleMelting, volatile cycles
DS201710-2249
2017
Hirschmann, M.M.Mjumder, S., Hirschmann, M.M.The origin of volatiles in the Earth's mantle.Geochemistry, Geophysics, Geosystems, Vol. 18, 8, pp. 3078-3092.Mantlevolatiles

Abstract: The Earth's deep interior contains significant reservoirs of volatiles such as H, C, and N. Due to the incompatible nature of these volatile species, it has been difficult to reconcile their storage in the residual mantle immediately following crystallization of the terrestrial magma ocean (MO). As the magma ocean freezes, it is commonly assumed that very small amounts of melt are retained in the residual mantle, limiting the trapped volatile concentration in the primordial mantle. In this article, we show that inefficient melt drainage out of the freezing front can retain large amounts of volatiles hosted in the trapped melt in the residual mantle while creating a thick early atmosphere. Using a two-phase flow model, we demonstrate that compaction within the moving freezing front is inefficient over time scales characteristic of magma ocean solidification. We employ a scaling relation between the trapped melt fraction, the rate of compaction, and the rate of freezing in our magma ocean evolution model. For cosmochemically plausible fractions of volatiles delivered during the later stages of accretion, our calculations suggest that up to 77% of total H2O and 12% of CO2 could have been trapped in the mantle during magma ocean crystallization. The assumption of a constant trapped melt fraction underestimates the mass of volatiles in the residual mantle by more than an order of magnitude.
DS201801-0011
2017
Hirschmann, M.M.Dalou, C., Hirschmann, M.M., von der Handt, A., Mosenfelder, J., Armstrong, L.S.Nitrogen and carbon fractionation during core-mantle differentiation at shallow depth.Earth and Planetary Science Letters, Vol. 458, 1, pp. 141-151.Mantlecarbon

Abstract: One of the most remarkable observations regarding volatile elements in the solar system is the depletion of N in the bulk silicate Earth (BSE) relative to chondrites, leading to a particularly high and non-chondritic C:N ratio. The N depletion may reflect large-scale differentiation events such as sequestration in Earth's core or massive blow off of Earth's early atmosphere, or alternatively the characteristics of a late-added volatile-rich veneer. As the behavior of N during early planetary differentiation processes is poorly constrained, we determined together the partitioning of N and C between Fe–N–C metal alloy and two different silicate melts (a terrestrial and a martian basalt). Conditions spanned a range of fO2 from ?IW?0.4 to ?IW?3.5 at 1.2 to 3 GPa, and 1400?°C or 1600?°C, where ?IW is the logarithmic difference between experimental fO2 and that imposed by the coexistence of crystalline Fe and wüstite. N partitioning ( ) depends chiefly on fO2, decreasing from to with decreasing fO2. also decreases with increasing temperature and pressure at similar fO2, though the effect is subordinate. In contrast, C partition coefficients () show no evidence of a pressure dependence but diminish with temperature. At 1400?°C, partition coefficients increase linearly with decreasing fO2 from to At 1600?°C, however, they increase from ?IW?0.7 to ?IW?2 ( to ) and decrease from ?IW?2 to ?IW?3.3 . Enhanced C in melts at high temperatures under reduced conditions may reflect stabilization of C–H species (most likely CH4). No significant compositional dependence for either N or C partitioning is evident, perhaps owing to the comparatively similar basalts investigated. At modestly reduced conditions (?IW?0.4 to ?2.2), N is more compatible in core-forming metal than in molten silicate ( ), while at more reduced conditions (?IW?2.2 to ?IW?3.5), N becomes more compatible in the magma ocean than in the metal phase. In contrast, C is highly siderophile at all conditions investigated (). Therefore, sequestration of volatiles in the core affects C more than N, and lowers the C:N ratio of the BSE. Consequently, the N depletion and the high C:N ratio of the BSE cannot be explained by core formation. Mass balance modeling suggests that core formation combined with atmosphere blow-off also cannot produce a non-metallic Earth with a C:N ratio similar to the BSE, but that the accretion of a C-rich late veneer can account for the observed high BSE C:N ratio.
DS201907-1589
2019
Hirschmann, M.M.Zhang, Z., Qin, T., Pommier, A., Hirschmann, M.M.Carbon storage in Fe-Ni-S liquids in the deep upper mantle and its relation to diamond and Fe-Ni alloy precipitation.Earth and Planetary Science Letters, Vol. 520, pp. 164-174.Mantlediamond genesis

Abstract: To better understand the role of sulfide in C storage in the upper mantle, we construct a thermodynamic model for Fe-Ni-S-C sulfide melts and consider equilibrium between sulfide melts, mantle silicates, Fe-Ni alloy, and diamond. The sulfide melt model is based upon previous parameterization of Fe-Ni-S melts calibrated at 100 kPa, which we have extended to high pressure based on volumetric properties of end-member components. We calculate the behavior of C in the sulfide melt from empirical parameterization of experimental C solubility data. We calculate the continuous compositional evolution of Fe-Ni sulfide liquid and associated effects on carbon storage at pressure and redox conditions corresponding to mantle depths of 60 to 410 km. Equilibrium and mass balance conditions were solved for coexisting Fe-Ni-S melt and silicate minerals (olivine [(Mg,Fe,Ni)2SiO4], pyroxene [(Mg,Fe)SiO3]) in a mantle with 200 ppmw S. With increasing depth and decreasing oxygen fugacity (fO2), the calculated melt (Fe+Ni)/S atomic ratio increases from 0.8-1.5 in the shallow oxidized mantle to 2.0-10.5 in the reduced deep upper mantle (>8 GPa), with Fe-Ni alloy saturation occurring at >10 GPa. Compared to previous calculations for the reduced deep upper mantle, alloy saturation occurs at greater depth owing to the capacity of sulfide melt to dissolve metal species, thereby attenuating the rise of Fe and Ni metal activities. The corresponding carbon storage capacity in the metal-rich sulfide liquid rises from negligible below 6 GPa to 8-20 ppmw at 9 GPa, and thence increases sharply to 90-110 ppmw at the point of alloy saturation at 10-12 GPa. The combined C storage capacity of liquid and solid alloy reaches 110-170 ppmw at 14 GPa. Thus, in the deep upper mantle, all carbon in depleted sources (10-30 ppmw C) can be stored in the sulfide liquid, and alloy and sulfide liquids host a significant fraction of the C in enriched sources (30-500 ppmw C). Application of these results to the occurrences of inferred metal-rich sulfide melts in the Fe-Ni-S-C system and inclusions in diamonds from the mantle transition zone suggests that oxidization of a reduced metal-rich sulfide melt is an efficient mechanism for deep-mantle diamond precipitation, owing to the strong effect of (Fe+Ni)/S ratio on carbon solubility in Fe-Ni-S melts. This redox reaction likely occurs near the boundary between oxidized subducted slabs and the reduced ambient peridotitic mantle.
DS1996-0634
1996
Hirschmann, M.N.Hirschmann, M.N., Stolper, E.M.A possible role for garnet pyroxenite in the origin of the garnet signature in Mid Ocean Ridge Basalt (MORB).Contributions to Mineralogy and Petrology, Vol. 124, No. 2, pp. 185-208.MantleGeochemistry, Garnet pyroxenite
DS201810-2294
2018
Hirt, A.M.Balashova, A., Mattsson, H.B., Hirt, A.M.New tephrostratigraphic data from Lake Emakat ( northern Tanzania): implications for the eruptive history of the Oldoinyo Lengai volcano. ( melilitites)Journal of African Earth Sciences, Vol. 147, pp. 374-382.Africa, Tanzaniadeposit - Oldoinyo Lengai

Abstract: The northern Tanzanian sector of the Gregory Rift is an area of an active continental rifting, in which sedimentation processes are strongly affected by volcanism. Due to limited stratigraphic exposure, the volcanic record of the region is rather sparse, and assigning volcanic centres for the individual eruptions is difficult. This study presents new data on the tephrostratigraphy of the sedimentary sequence of Lake Emakat, Empakaai Crater, northern Tanzania. Seven volcanic ash layers are identified and described from a 1.1-m core of lake sediments. Geochemical, mineralogical, petrographic and magnetic analyses show that: (1) all ash layers are products of highly explosive eruptions of melilite-bearing magmas; (2) most of the eruptions originate from a complex magmatic system; (3) all ash horizons are very well preserved in the lake environment; and (4) there are significant fluctuations of the bulk magnetic susceptibility of the lacustrine sediments which is related to microtephra from additional eruptions, the result of detritus, washed from the shore during periods of strong lake level fluctuations or periods of high erosion rates, or simply by the contamination by the material from the ash layers. Based on geochemistry and mineralogy of the seven identified ash layers in Lake Emakat, combined with the eruption ages from ¹?C datings, we can pinpoint Oldoinyo Lengai volcano as the source of these specific layers. The combination of this new data with existing chronological data from Ryner et al. (2007), retrieved from the same core, provides precise ages of the voluminous highly explosive eruptions in this region of East Africa during the Pleistocene-Holocene transition.
DS1996-0635
1996
Hirth, G.Hirth, G., Kohlstedt, D.L.Water in the oceanic upper mantle: implications for rheology, melt extraction and evolution of lithosphereEarth and Plan. Sci. Letters, Vol. 144, No. 1-2, Oct. 1, pp. 93-MantleTectonics, geodynamics, Rheology
DS2001-0305
2001
Hirth, G.Escartin, J.,Hirth, G., Evans, B.Strength of slightly serpentinized peridotites: implications for the tectonics of oceanic lithosphere.Geology, Vol. 29, No. 11, Nov. pp. 1023-6.MantlePeridotites, Tectonics - rheology
DS2002-0724
2002
Hirth, G.Hirth, G.Laboratory constraints on the rheology of the upper mantlePlastic Deformation of Minerals and Rocks, Geological Society of America, No. 51, Chapter 4, pp.97-116.MantleGeodynamics
DS2002-0725
2002
Hirth, G.Hirth, G.Laboratory constraints on the rheology of the upper mantleReviews in Mineralogy and Geochemistry, Vol. 51, pp. 97-120.MantleRheology
DS2003-1561
2003
Hirth, G.Zhu, W., Hirth, G.A network model for permeability in partially molten rocksEarth and Planetary Science Letters, Vol. 212, 3-4, pp. 407-416.MantleMelting
DS200412-0836
2002
Hirth, G.Hirth, G.Laboratory constraints on the rheology of the upper mantle.Plastic Deformation of Minerals and Rocks, Geological Society of America, Mineralogy and Geochemistry Series, No. 51, Chapter 4, pp.97-116.MantleGeodynamics
DS200412-0837
2002
Hirth, G.Hirth, G.Laboratory constraints on the rheology of the upper mantle.Reviews in Mineralogy and Geochemistry, Vol. 51, pp. 97-120.MantleRheology
DS200412-2229
2003
Hirth, G.Zhu, W., Hirth, G.A network model for permeability in partially molten rocks.Earth and Planetary Science Letters, Vol. 212, 3-4, pp. 407-416.MantleMelting
DS201212-0350
2012
Hirth, G.Kelemen, P.B., Hirth, G.Reaction driven cracking during retrograde metamorphism: olivine hydration and carbonation.Earth and Planetary Science Letters, Vol. 345-348, pp. 81-89.MantleMetasomatism
DS201312-0186
2013
Hirth, G.Dasgupta, R., Mallik, A., Tsuno, K., Withers, A.C., Hirth, G., Hirschmann, M.M.Carbon dioxide rich silicate melt in the Earth's upper mantle.Nature, Vol. 493, Jan. 10, pp. 211-215.MantleMelting
DS201312-0371
2013
Hirth, G.Havlin, C., Prmentier, E.M., Hirth, G.Mineral associations in diamonds from the lowermost upper mantle and uppermost lower mantle.Earth and Planetary Science Letters, Vol. 376, pp. 20-28.MantleMelting
DS201809-2012
2018
Hirth, G.Clerc, F., Behn, M.D., Parmentier, E.M., Hirth, G.Predicting rates and distribution of carbonate melting in oceanic upper mantle: implications for seismic structure and global carbon cycling.Geophysical Research Letters, doi.org/10.1029/2018GL078142Mantlemelting

Abstract: Despite support from indirect observations, the existence of a layer of carbon?rich, partially molten rock (~60 km) below oceanic crust, made possible by the presence of CO2, remains uncertain. In particular, abrupt decreases in the velocity that seismic waves propagate at depths of 40-90 and 80-180 km beneath the ocean basins remain unexplained. In this study, we test whether these seismic discontinuities can be attributed to the presence of a layer of carbon?rich melt. Melt generation occurs only where the mantle is upwelling; thus, we predict the locations of carbonate?enhanced melting using a mantle convection model and compare the resulting melt distribution with the seismic observations. We find that the shallower seismic discontinuities (at 40? to 90?km depth) are not associated with regions of predicted melting but that the deeper discontinuities (80-180 km) occur preferentially in areas of greater mantle upwelling—suggesting that these deep observations may reflect the presence of localized melt accumulation at depth. Finally, we show that carbonate melting far from mid?ocean ridges produces an additional CO2 flux previously overlooked in deep carbon cycle estimates, roughly equivalent to the flux of CO2 due to seafloor volcanism.
DS202110-1602
2021
Hirth, G.Boneh, Y., Chin, E.J., Hirth, G.Microstructural analysis of a mylonitic mantle xenolith sheared laboratory-like strain rates from the edge of the Wyoming craton.Minerals MDPI, Vol. 11, 995, 18p. PdfUnited States, Montana, Wyoming, Utah, Canada, Alberta, Saskatchewancraton

Abstract: Combined observations from natural and experimental deformation microstructures are often used to constrain the rheological properties of the upper mantle. However, relating natural and experimental deformation processes typically requires orders of magnitude extrapolation in strain rate due to vastly different time scales between nature and the lab. We examined a sheared peridotite xenolith that was deformed under strain rates comparable to laboratory shearing time scales. Microstructure analysis using an optical microscope and electron backscatter diffraction (EBSD) was done to characterize the bulk crystallographic preferred orientation (CPO), intragrain misorientations, subgrain boundaries, and spatial distribution of grains. We found that the microstructure varied between monophase (olivine) and multiphase (i.e., olivine, pyroxene, and garnet) bands. Olivine grains in the monophase bands had stronger CPO, larger grain size, and higher internal misorientations compared with olivine grains in the multiphase bands. The bulk olivine CPO suggests a dominant (010)[100] and secondary activated (001)[100] that are consistent with the experimentally observed transition of the A to E-types. The bulk CPO and intragrain misorientations of olivine and orthopyroxene suggest that a coarser-grained initial fabric was deformed by dislocation creep coeval with the reduction of grain size due to dynamic recrystallization. Comparing the deformation mechanisms inferred from the microstructure with experimental flow laws indicates that the reduction of grain size in orthopyroxene promotes activation of diffusion creep and suggests a high activation volume for wet orthopyroxene dislocation creep.
DS202111-1763
2021
Hirth, G.Chin, E.J., Chilson-Parks, B., Boneh, Y., Hirth, G., Saal, A.E., Hearn, B.C., Hauri, E.H.The peridotite deformation cycle in cratons and the deep impact of subduction.Tectonophysics, Vol. 817, 229029, 22p. PdfUnited States, Wyomingdeposit - Homestead, Williams

Abstract: Xenoliths play a crucial role in interpretation of mantle deformation and geochemistry. The classic work of Mercier and Nicolas (1975) introduced the concept of the peridotite deformation cycle, which connected observed microstructures to a physical sequence of deformation. We revisit Mercier and Nicolas' original concept, bringing in new constraints using large area EBSD maps and associated microstructural datasets, analysis of water contents in nominally anhydrous minerals, and trace element chemistry of pyroxenes and garnets. We apply these techniques to a well-characterized suite of peridotite xenoliths from the Eocene-age Homestead and Williams kimberlites in the northwestern Wyoming Craton. Pyroxene water content and trace element mineral chemistries reveal ubiquitous hydrous metasomatism beneath the craton, most likely linked to the Cenozoic Laramide Orogeny. Homestead xenoliths primarily exhibit coarse protogranular and equigranular textures, B-type olivine fabrics, and generally elevated mineral water contents compared to Williams. Xenoliths from Williams are strongly deformed, with porphyroclastic and transitional textures containing annealed olivine tablets, mostly A-type olivine fabrics, and generally lower mineral water contents. As a whole, mantle from Homestead to Williams reflects a cratonic scale deformation cycle that likely initiated in Laramide times and lasted until the end of orogeny in the Eocene. At Williams, evidence for a rapid deformation “sub-cycle” within the main deformation cycle is preserved in the tablet-bearing xenoliths, corresponding to the enigmatic “transitional” texture of Mercier and Nicolas (1975). Our results suggest that this texture reflects interruption of the main deformation cycle by processes possibly related to a rapidly forming lithospheric instability and generation of the kimberlite magma - offering a new interpretation of this ambiguous peridotite texture. Collectively, our results incorporate typically disparate geochemical and textural datasets on xenoliths to shed new insights into how metasomatism, volatiles, and deformation are connected in the deep cratonic lithosphere.
DS200512-0652
2004
Hirth, J.A.Lizarralde, D., Gaherty, D., Collins, J.B., Hirth, J.A., Kim, S.D.Spreading rate dependence of melt extraction at mid-ocean ridges from mantle seismic refraction data.Nature, No. 7018, Dec. 9, pp. 744-746.MantleMelting
DS201511-1854
2015
Hisanaga, M.Kitawaki, H., Hisanaga, M., Yamamoto, M.Type 1b yellow to brownish yellow CVD synthetic diamonds seen at CGL.Journal of Gemmology, Vol. 34, 7, pp. 594-605.TechnologySynthetics

Abstract: In mid-2012, one of the international diamond grading laboratories in Antwerp reported undisclosed CVD synthetic diamonds, causing a stir in the diamond industry (Even-Zohar, 2012). Since then, reports of undisclosed CVD synthetics have also emerged from gem testing laboratories in India and China (D’ Haenens-Johanson et al., 2013; Song et al., 2014). Central Gem Laboratory (CGL) also reported on undisclosed over 1 ct size CVD synthetic diamonds (Kitawaki et al., 2013). Gem quality CVD products have been improved in their size and quality year after year, and a variety of colours have appeared. Most of the CVD synthetic diamonds reported previously are type II, however, recently some yellow CVD synthetic diamonds containing isolated substitutional nitrogen have been supplied to the gem market (Moe et al., 2014; Hainschwang, 2014). This report describes the gemmological features of fifteen yellow to brownish yellow type Ib CVD synthetic diamonds submitted to CGL without disclosure.
DS201901-0044
2018
Hisanaga, M.Kitawaki, H., Emori, K., Hisanaga, M., Yamamoto, M., Okano, M.LPHT treated pink CVD synthetic diamond.Gems & Gemology, Sixth International Gemological Symposium Vol. 54, 3, 1p. Abstract p. 267.Globalsynthetics

Abstract: Pink diamond is extremely popular among fancy-color diamonds, which has prompted numerous attempts to produce pink diamond artificially. Pink CVD synthetic diamonds appeared on the gem market around 2010. Their color was produced by a multistep process combining post-growth HPHT treatment to remove the brown hue and subsequent electron irradiation, followed by low-temperature annealing. Pink CVD synthetic diamonds treated only with low pressure and high temperature (LPHT), without additional post-growth irradiation, have also been reported but are rarely seen on the market. Recently, a loose pink stone (figure 1) was submitted to the Central Gem Laboratory in Tokyo for grading purposes. Our examination revealed that this 0.192 ct brilliant-cut marquise was a CVD synthetic diamond that had been LPHT treated. Visually, this diamond could not be distinguished from natural diamonds with similar color. However, three characteristics of CVD origin were detected: 1. C-H related absorption peaks between 3200 and 2800 cm-1, located with infrared spectroscopy 2. A luminescence peak at 737 nm, detected with photoluminescence (PL) spectroscopy 3. A trace of lamellar pattern seen in the DiamondView However, irradiation-related peaks such as at 1450 cm-1 (H1a), 741.1 nm (GR1), 594.3 nm, or 393.5 nm (ND1) that are seen in the pink CVD diamonds treated with common multi-step processes were not detected. The presence of four peaks at 3123, 2901, 2870, and 2812 cm-1 between 3200 and 2800 cm-1 suggests this stone was LPHT treated; the following observations indicate that it was not HPHT treated: 1) The 3123 cm-1 peak presumably derived from NVH0 disappears after a normal HPHT treatment. 2) The 2901, 2870, and 2812 cm-1 peaks are known to shift toward higher wavenumbers as the annealing temperature rises. Our own HPHT treatment experiments on CVDgrown diamonds proved that the 2902 and 2871 cm-1 peaks detected after 1600°C annealing shifted to 2907 and 2873 cm-1 after 2300°C annealing. The peak shift of 2901, 2870, and 2812 cm-1 is also related to the pressure during the annealing, as these peaks shifted to 2902, 2871, and 2819 cm-1 at the higher pressure of 7 GPa compared to 2900, 2868, and 2813 cm-1 at the ambient pressure under the same annealing temperature of 1600°C. 3) Absorption peaks at 7917 and 7804 cm-1 in the infrared region and at 667 and 684 nm in the visible range were also detected, which coincide with the features seen in LPHTtreated stones. From the combination of the intensity ratios of optical centers such as H3 and NV centers that were detected with PL measurement, this sample is presumed to have been treated with LPHT annealing at about 1500- 1700°C as a post-growth process. In recent years, CVD synthetic diamonds have been produced in a wider range of colors due to progress in the crystal growth techniques and post-growth treatments. Although HPHT treatment has been employed mainly to improve the color in a diamond, LPHT annealing may become widespread as the technique is further developed. Gemologists need to have deep knowledge about the optical defects in such LPHT-treated specimens.
DS1970-0715
1973
Hisckman, G.M.Hisckman, G.M., Dickins, W.G.H.The Lands and Peoples of East AfricaNairobi: Longman., 178P.Tanzania, East AfricaHistory, Kimberley
DS201511-1840
2015
Hishinuma, R.Harada, Y., Hishinuma, R., Terashima, C., Uetsuka, H., Nakata, K., Kondo, T., Yuasa, M., Fujishima, A.Rapid growth of diamond and its morphology by in-liquid plasma CVD.Diamond and Related Materials, in press available, 16p.TechnologySynthetics

Abstract: Diamond synthesis and its morphology by in-liquid plasma chemical vapor deposition (CVD) method are investigated in this study. Diamond films were grown on Si substrates from mixed alcohol solution. Very high growth rate of 170 ?m/h was achieved by this method. Microcrystalline and nanocrystalline diamond films were formed in different conditions. In the case of microcrystalline film, the shapes of diamond grains depend on the location in the film. All morphological differences in this study can be explained by the same mechanism of conventional gas phase CVD method. It means diamond morphology by in-liquid plasma CVD method can be controlled by process parameters as well as gas phase CVD method.
DS1859-0114
1854
Hislop, S.Hislop, S., Hunter, R.Geology of the Nagpur Central IndiaQuarterly Journal of the Geological Society of London., Vol. 10, PP. 470-473.India, Nagpur, Central IndiaDiamond conglomerates
DS1859-0117
1855
Hislop, S.Hislop, S., Hunter, R.On the Geology and Fossils of the Neighbourhood of Nagpur, Central india.Quarterly Journal of the Geological Society of London., Vol. 11, PT. 1, PP. 354-356.India, Nagpur, Central IndiaDiamond Conglomerates
DS1860-0846
1894
Hisserich, L.T.Hisserich, L.T.Die Idar-obersteiner IndustrieOberstein: Druck Und Verlag Der R. Grub'schen., BUCHHANDLUNGEurope, GermanyDiamond Cutting
DS2003-0558
2003
Hitchcock, R.Harris, J.R., Rogge, D., Hitchcock, R., Ijewliw, O., Wright, D.Mapping lithology in Canada's high arctic: application of hyper spectral Data31st Yellowknife Geoscience Forum, p. 37. (abst.Nunavut, Baffin IslandRemote sensing - hyperspectral
DS200412-0796
2003
Hitchcock, R.Harris, J.R., Rogge, D., Hitchcock, R., Ijewliw, O., Wright, D.Mapping lithology in Canada's high arctic: application of hyper spectral Data.31st Yellowknife Geoscience Forum, p. 37. (abst.Canada, Nunavut, Baffin IslandRemote sensing - hyperspectral
DS200612-0537
2005
Hitchcock, R.Harris, J.R., Rogge, D., Hitchcock, R., Ijewliw, O., Wright, D.Mapping lithology in Canada's Arctic: application of hyper spectral dat a using the minimum noise fraction transformation and matched filtering.Canadian Journal of Earth Sciences, Vol. 41, 12, Dec. pp. 2173-2193.Canada, Nunavut, Baffin IslandMapping - hyperspectral, lithology
DS200912-0303
2009
Hitchie, L.Hitchie, L., Fedortchouk, Y.Experimental study of diamond dissolution in Cl-H2O systems: implications for mechanisms of diamond oxidation and kimberlitic fluids.EOS Transaction of AGU, Vol. 90, no. 22 1p. abstractTechnologyDiamond oxidation
DS201312-0391
2013
Hitchie, L.Hitchie, L., Pell, J., Scott Smith, B.H., Russell, J.K.The CH-6 kimberlite, Canada: textural and mineralogical features and their relevance to volcanic facies and magma batch interpretation.GAC-MAC 2013 SS4: Diamond: from birth in the mantle to emplacement in kimberlite, abstract onlyCanada, Nunavut, Baffin IslandDeposit - CH-6
DS1996-0636
1996
Hitchon, B.Hitchon, B.Rapid evaluation of the hydrochemistry of a sedimentary basin using only standard formation water analysis:Applied Geochemistry, Vol. 11, No. 6, Nov. 1, pp. 789-796Alberta, SaskatchewanGeochemistry, Williston Basin
DS1986-0891
1986
Hitoh, O.Zashu, S., Ozima, M., Hitoh, O.K-Ar isochron dating of Zaire cubic diamondsNature, Vol. 323, No. 6090 October 23, pp. 710-712Democratic Republic of CongoGeochronology
DS200612-0675
2006
HittlemanKeller, G.R., Hildenbrand, Kucks, Webring, Briesacher, Rujawitz, Hittleman, Roman, Winester, Aldouri et al.A community effort to construct a gravity database for the United States and an associated Web portal.In: Sinha, A.K. Geoinformatics: data to knowledge, GSA Special Paper, 397, 397, pp.21-34 rUnited StatesGeophysics - gravity data
DS202205-0688
2022
Hitzman, M.Hutchinson, M., Slezak, P., Wendtlandt, R., Hitzman, M.Rare earth element enrichment in the weathering profile of the Bull Hill carbonatite at Bear Lodge, Wyoming, USA.Economic Geology, Vol. 117, pp. 813-831.United States, Wyomingdeposit - Bull Hill

Abstract: Bull Hill is a carbonatite diatreme within the Paleogene Bear Lodge Carbonatite Complex in Wyoming, USA. Rare earth element (REE)-bearing carbonate, fluorocarbonate, phosphate, and oxide minerals occur within near-vertical carbonatite dikes on the western margin of Bull Hill. Changes in mineralogy and REE concentrations with depth are ascribed mainly to late-stage magmatic-hydrothermal and supergene alteration. Approximately 35 m of drill core from Bull Hill was analyzed and encompasses least altered, weakly weathered, and moderately weathered carbonatite. The least altered carbonatite contains magmatic burbankite, typically as inclusions within Mn-rich calcite (stage I). Secondary REE-bearing minerals, which pseudomorphically replaced unidentified hexagonal phenocrysts, include ancylite, bastnäsite with synchysite/parisite, and an unidentified Sr-Ca-REE-phosphate (stage II). These replacive minerals generated small amounts of incipient porosity (~7-8%) and are largely stable in the lower portion of the weathering profile. Progressive weathering (stages III and IV) of the carbonatite involved the oxidation of pyrite to iron oxides and iron hydroxides, dissolution of calcite and strontianite, and the replacement of Mn-rich calcite by manganese oxides. These mineralogical changes resulted in an ~40% porosity gain in the core studied here. The volumetric concentration of weathering resistant REE-bearing minerals resulted in REE enrichment from an average of 5.4 wt % in the least weathered carbonatite to an average of 12.6 wt % in moderately weathered carbonatite, and to an overall increase in REE ore tenor of two to three times compared to the least altered carbonatite. Isocon plots confirm the increased concentration of REEs in the weathered carbonatite and demonstrate that REEs, along with TiO2, Ta, Nb, Zr, and Hf, were conserved in the lower weathered zone.
DS1997-0508
1997
Hitzman, M.W.Hitzman, M.W.The next generation of mineral geologists rethinking industry- academicliaisonsSeg Newsletter, No. 21, Oct. pp. 6-7GlobalIndustry - academia, Research, discoveries
DS2002-0210
2002
Hitzman, M.W.Broughton, D.W., Hitzman, M.W., Stephens, A.J.Exploration history and geology of the Kansanshi Cu Au deposit, ZambiaSociety of Economic Geologists Special Publication, No.9,pp.141-53.ZambiaCopper, gold, copperbelt, Deposit - Kansanshi
DS2002-0726
2002
Hitzman, M.W.Hitzman, M.W.New papers on the Candelaria district, Chile, allow development of an improved exploration model ...Seg Newsletter, No. 49, April, pp. 23,26.ChileModel - iron, oxide copper, gold, Deposit - Candelaria
DS201605-0915
2016
Hitzman, M.W.Verplanck, P.L., Hitzman, M.W.Rare earth and critical elements in ore deposits.SEG Reviews in Economic Geology, editors Verplanck, P.L., Hitzman, M.W., No. 18, pp. 1-4.TechnologyRare earths
DS201702-0248
2016
Hitzman, M.W.Verplanck, P.L., Hitzman, M.W.Rare earth and critical elements in ore deposits.Reviews in Economic Geology, Vol. 18, 365p. $ 72. CD/pdf/printGlobalBook - rare earth

Abstract: This special volume provides a comprehensive review of the current state of knowledge for rare earth and critical elements in ore deposits. The first six chapters are devoted to rare earth elements (REEs) because of the unprecedented interest in these elements during the past several years. The following eight chapters describe critical elements in a number of important ore deposit types. These chapters include a description of the deposit type, major deposits, critical element mineralogy and geochemistry, processes controlling ore-grade enrichment, and exploration guides. This volume represents an important contribution to our understanding of where, how, and why individual critical elements occur and should be of use to both geoscientists and public policy analysts.
DS1990-1147
1990
Hiyagon, H.Ozima, M., Azuma, S., Zashu, S., Hiyagon, H.224 Pu Fissiogenic Xe in mantle21st. Lunar And Planetary Science Conference, March 12-16, Houston, March 16 presentationGlobalMantle, Xenon
DS1995-2121
1995
Hiyagon, H.Zashu, S., Hiyagon, H.Degassing mechanisms of noble gases from carbonado diamondsGeochimica et Cosmochimica Acta ., Vol. 59, No. 7, pp. 1321-1328.Central AfricaUbangi area, Carbonados
DS1997-0996
1997
Hiyagon, H.Sasada, T., Hiyagon, H., Bell, K., Erihara, M.Mantle derived noble gases in carbonatitesGeochimica et Cosmochimica Acta, Vol. 61, No. 19, Oct. pp. 4219-28.Brazil, Ontario, QuebecCarbonatite, Jacupirigna, Tapira, Borden, Oka, Prairie, Poohbah
DS201112-0435
2011
Hiyate, A.Hiyate, A.Peregrine preps Chidliak for bulk sampling.Diamonds in Canada Magazine, Northern Miner, November pp. 22-23.Canada, Nunavut, Baffin IslandHistory - Peregrine
DS201112-0436
2011
Hiyate, A.Hiyate, A.On the diamond trail: a look at what Canadian listed explorers are up to around the world.Diamonds in Canada Magazine, Northern Miner, May pp. 12-20.GlobalNews item - diamond companies - brief outline
DS201112-0437
2010
Hiyate, A.Hiyate, A.Peregrine's 'quantum leap' at Chidliak.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 10-14.Canada, Nunavut, Baffin IslandNews item - Peregrine
DS201112-0438
2011
Hiyate, A.Hiyate, A.Pat Sheahan: a diamond-seeker's best friend. Geologist founded the Sheahan-MDRU literature service.Diamonds in Canada Magazine, Northern Miner, November pp. 6- 10.Profile - Sheahan-MDRU
DS201212-0301
2012
Hiyate, A.Hiyate, A.Unable to go big .. BHP and Rio go home .. Mining giants declare diamond assets for sale.Diamonds in Canada Magazine, Northern Miner, May pp. 6-7, 22.Canada, Northwest TerritoriesEconomics
DS201212-0302
2012
Hiyate, A.Hiyate, A.Anglo takes the reins at De Beers.Diamonds in Canada Magazine, Northern Miner, May pp. 8-9.GlobalEconomics
DS201312-0392
2013
Hiyate, A.Hiyate, A.Bob Gannicott on Dominion Diamond's new vision.Diamonds in Canada Magazine, Northern Miner, May pp. 6-9.Canada, Northwest TerritoriesDeposit - Ekati
DS201312-0393
2013
Hiyate, A.Hiyate, A.Treasure hunters…. Brief roundup of active diamond explorers.Diamonds in Canada Magazine, Northern Miner, May pp. 12-17.GlobalCompanies
DS201412-0361
2014
Hiyate, A.Hiyate, A.Dominion Diamond banks on Ekati. Diamond pureplay…Diamonds in Canada Magazine, Northern Miner, May pp. 8-11, 22.Canada, Northwest TerritoriesDeposit - Ekati
DS201412-0362
2014
Hiyate, A.Hiyate, A.Lukas lundin talks diamonds: an exclusive interview with the mining mogul. Chairman of Lucara (Karowe)Diamonds in Canada Magazine, Northern Miner, November pp. 5-7.Africa, BotswanaHistory of Lucara
DS201412-0363
2014
Hiyate, A.Hiyate, A.Canada's mini staking rush…. Kennady Diamonds, Proxima, Canterra, Margaret Lake, North Arrow, Prima, Denendah, Arctic Star, Alto, Strike, Gem Oil, Diamonds in Canada Magazine, Northern Miner, November pp. 14-17, 22CanadaCompanies - brief overview
DS201512-1927
2015
Hiyate, A.Hiyate, A.Botswana beckons. Prolific diamond nation attracts explorers.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 14-17.Africa, BotswanaOverview of companies
DS201606-1091
2016
Hiyate, A.Hiyate, A.Tough year tests Dominion.Northern Miner Diamonds in Canada, May pp. 5-7.Canada, Northwest TerritoriesDominion Diamonds
DS201606-1092
2016
Hiyate, A.Hiyate, A.Rock hounds .. Annual roundup of Canadian listed diamond miners, developers and active juniors.Northern Miner Diamonds in Canada, May pp. 12-17.GlobalDiamond companies
DS201712-2689
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Author Index
A-An Ao+ B-Bd Be-Bk Bl-Bq Br+ C-Cg Ch-Ck Cl+ D-Dd De-Dn Do+ E F-Fn Fo+ G-Gh Gi-Gq Gr+ H-Hd He-Hn Ho+ I J K-Kg Kh-Kn Ko-Kq Kr+ L-Lh
Li+ M-Maq Mar-Mc Md-Mn Mo+ N O P-Pd Pe-Pn Po+ Q R-Rh Ri-Rn Ro+ S-Sd Se-Sh Si-Sm Sn-Ss St+ T-Th Ti+ U V W-Wg Wh+ X Y Z
 
 

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