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SDLRC - Impact Crater


The Sheahan Diamond Literature Reference Compilation - Scientific and Media Articles based on Major Keyword - Impact Crater
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 announcements called 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 Keyword Index
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
Each article reference in the SDLRC is tagged with one or more key words assigned by Pat Sheahan to highlight the main topics of the article. In an effort to make it easier for users to track down articles related to a specific topic, KRO has extracted these key words and developed a list of major key words presented in this Key Word Index to which individual key words used in the article reference have been assigned. In most of the individual Key Word Reports the references are in crhonological order, though in some such as Deposits the order is first by key word and then chronological. Only articles classified as "technical" (mainly scientific journal articles) and "media" (independent media articles) are included in the Key Word Index. References that were added in the most recent monthly update are highlighted in yellow.

An Impact Crater is the depression created in the earth's crust when struck by an asteroid or meteor. The moon is full of such completely preserved impact craters, but on the earth they are only preserved when fairly recent or within a stable craton. Scientific articles about impact craters are relevant to diamonds because major impacts can affect melting behavior within the earth's mantle which leads to magmatism which in turn can spawn kimberlite emplacement. Extraterrestrial impacts also create high pressure and high temperature conditions that support diamond formation, though so-called impact diamonds tend to be small and have a hexagonal crystal structure similar to graphite.

Impact Crater
Posted/
Published
AuthorTitleSourceRegionKeywords
DS1900-0077
1901
Schenck, A.Ueber Den Geitse' Gubib, Einen Porphryischen Stratovulkan Deutsch-suedwest Afrikas.Zeitschr. Deut. Geol. Ges., Vol. 53, PP. 54-55. ALSO: ZEITSCHR. F. PRAKT. GEOL., P. 419.Africa, NamibiaCarbonatite, Impact Structure, Kimberlite
DS1970-0494
1972
Crawford, A.R.Possible Impact Structure in IndiaNature., Vol. 237, MAY 17TH. P. 96.IndiaImpact Structure, Geobleme
DS1987-0128
1987
Crosta, A.P.Impact structures in BrasilBraunschweig Wiesbaden Vieweg, pp. 30-38BrazilImpact crater
DS1987-0162
1987
Dressler, B.O., Morrison, G.G., Peredery, W.V., Rao, B.V.The Sudbury structure, Ontario, Canada- a ReviewBraunschweig Wiesbaden Vieweg, pp. 39-68OntarioSudbury, Impact structure
DS1988-0458
1988
Melosh, H.J.Impact cratering: a geologic processOxford University of Press, 272p. $ 65.00GlobalCrater, meteorite
DS1988-0472
1988
Milstein, R.L.Calvin 28 cryptoexplosion disturbance, Cass County,Michigan: evidence for impact originNational Technical Information Service, Lunar and Planetary Institute Global Catastrophes in Earth History, No. N89-21287/2 pp. 122-123. $ 28.95MichiganImpact crater
DS1988-0499
1988
Nayak, V.K.Lonar Lake and co-linear carbonatites of western IndiaJournal of Geological Society India, Vol. 32, No. 5, pp. 433-434IndiaImpact crater, Carbonatite
DS1989-0952
1989
Masaytis, V.L.The economic geology of impact cratersInternational Geology Review, Vol. 31, No. 9, September pp. 922-933RussiaImpact craters
DS1990-0748
1990
Izett, G.A.The Cretaceous/Tertiary boundary interval, Raton Basin, Colorado and New Mexico and its content of shock metamorphosed minerals evidence relevant K/TboundaryGeological Society of America, Paper No. 249, 104p. $ 30.00 United StatesColorado, New MexicoMineralogy, Impact structure
DS1991-0150
1991
Borodzich, E.V., Korotkin, M.R., et al.The origin of ring structuresDoklady Academy of Sciences USSR, Earth Science Section, Vol. 311, No. 1-6, Nov. pp. 50-53RussiaStructure, Ring structures
DS1991-1023
1991
Lunar and Planetary Information BulletinChicxulub - site of the K/T impactor?Lunar and Planetary Information Bulletin, No. 60, August pp. 3-6GlobalImpact craters, General interest
DS1991-1069
1991
Mashchak, M.S.Geologic setting in Kara and Ust-Kara at time of formation of the impactcraterInternational Geology Review, Vol. 33, No. 5, May pp. 423-432RussiaImpact crater, Kara
DS1991-1539
1991
Selivanovskaya, T.V., Mashchak, M.S., Masaytis, V.L.Impact breccias and impactites of the Kara and Ust-Kara astroblemesInternational Geology Review, Vol. 33, No. 5, May pp. 448-477RussiaImpact crater, Kara
DS1992-1200
1992
Pilkington, M., Grieve, R.A.F.The geophysical signature of terrestrial impact cratersReviews of Geophysics, Vol. 30, No. 2, May pp. 161-181CanadaGeophysics -gravity, Impact craters
DS1993-0422
1993
Evans, N.J., Gregoire, D.C.Use of platinum group elements for impactor identification terrestrial impact craters and Cretaceous Tertiary boundaryGeochimica et Cosmochimica Acta, Vol. 57, No.15, pp. 3737-3748GlobalImpact craters, platinum group elements (PGE)
DS1993-0580
1993
Grieve, R.A.F.Impact craters: lessons from and for the earthVistas in Astronomy, Vol. 36, pp. 203-230.GlobalAstronomy - solar system, Impact craters
DS1993-0581
1993
Grieve, R.A.F.Impact craters: when will enough be enough?Nature, Vol. 363, No. 6431, June 24, pp. 670-671GlobalImpact craters
DS1993-0582
1993
Grieve, R.A.F.Impact craters: lessons from and for the earthVistas in Astronomy, Vol. 36, pp. 203-230QuebecImpact craters
DS1994-0660
1994
Grieve, R.A.F.Impact: a natural hazard in planetary evolutionEpisodes, Vol. 17, No. 1/2, pp. 9-17GlobalImpacts
DS1994-0662
1994
Grieve, R.A.F., Masaitis, V.L.The economic potential of terrestrial impact cratersInternational Geology Review, Vol. 36, No. 2, February pp. 105-151GlobalImpact craters
DS1994-0778
1994
Hodge, P.Meteorite craters and impact structures of the earthCambridge University of Press Book, 125p.United States, Canada, Latin America, Australia, Europe, AfricaMeteorites, Impact craters
DS1994-1121
1994
Masaitis, V.L.Diamondiferous impactites, their distribution and petrogenesis. (Russian)Regional Geology and Metallogeny (Russian), No. 1, p. 121RussiaImpact crater
DS1994-1445
1994
Reimold, W.U.Impact cratering - a review with special reference to the economic importance of impact structuresUniversity of Witwatersrand Economic Geology Research Unit, No. 283, 25pSouthern AfricaImpact structures, metallogeny, Review
DS1994-1446
1994
Reimold, W.U.Impact cratering - a review, with special reference to the economic importance of impact structures.Economic Geology Research Unit, U. of Wits, No. 283, 26p.Southern AfricaImpact structures, Diamond deposits p. 14
DS1995-0641
1995
Glikson, A.Y.Asteroid/comet mega-impacts may have triggered major episodes of crustalevolution.Eos, Vol. 76, No. 6, Feb. 7, p. 54, 55, 56.GlobalImpact structures, Tectonics
DS1995-1176
1995
Master, S.Meteorite impact structures in ZimbabweCentennial Geocongress (1995) Extended abstracts, Vol. 1, p. 574-576. abstractZimbabweMeteorite, Impact structure
DS1995-1557
1995
Reimold, W.U.Pseudotachylite in impact structures -generation by friction melting and stock brecciation? a review -disc-Earth Science Reviews, Vol. 39, No. 3-4, Dec. pp.247-266GlobalImpact structures, Review
DS1995-1558
1995
Reimold, W.U.Pseudotachyite in impact structures - generation by friction melting and shock brecciation? review and discEarth Science Reviews, Vol. 39, pp. 247-265OntarioImpact structures, Review
DS1995-1690
1995
Scott Smith, B.H., Orr, R.G., Robertshaw, P., Avery, R.W.Geology of the Fort a la Corne kimberlites, Saskatchewan #2Proceedings of the Sixth International Kimberlite Conference Abstracts, pp. 543-545.SaskatchewanGeology, crater, age, rock types, Deposit -Fort a la Corne
DS1995-1918
1995
Toon, O., Zahnle, K.All impacts great and smallGeotimes, Vol. 40, No. 3, March pp. 21-23GlobalImpacts
DS1996-0009
1996
AGSOAustralian impact structuresAgso, Vol. 16, No. 4, pp. 371-620AustraliaImpact structures, Table of contents
DS1996-0107
1996
Becker, L., Poreda, R.J., Bada, J.L.Extraterrestrial helium trapped in fullerenes in the Sudbury ImpactStructureScience, Vol. 272, April 12, pp. 249-252OntarioSIC, Impact crater
DS1996-0566
1996
Grieve, R.A.F., Masaitis, V.L.Impact diamondsGeological Survey of Canada, LeCheminant ed, OF 3228, pp. 183-186.CanadaImpact structure, Carbonados
DS1996-0723
1996
Keiswetter, D., Black, R., Steeples, D.Seismic reflection analysis of the Manson Impact Structure, IowaJournal of Geophysical Research, Vol. 101, No. 3, March 10, pp. 5823-5834.IowaStructure, Impact structure
DS1996-1292
1996
Sharpton, V.L., Dressler, B.O., et al.New constraints on the Slate Islands impact structure, Ontario. CanadaGeology, Vol. 24, No. 9, Sept. pp. 851-854.OntarioImpact structure, Slate Islands
DS1997-0397
1997
Gibson, R.L., Stevens, G.Regional metamorphism due to anorogenic intracratonic magmatismEconomic Geology Research Unit, No. 311, 23pSouth AfricaVerdefort Dome, impact structure, Kaapvaal Craton, Mantle derived magmas
DS1997-0729
1997
Marakushev, A.A.Ore bearing potential of impact ring structureGeology of Ore Deposits, Vol. 38, No. 6, pp. 442-453.RussiaImpact structure, Puchezh-Katun, Popigai, Diamond
DS1997-0729
1997
Marakushev, A.A.Ore bearing potential of impact ring structureGeology of Ore Deposits, Vol. 38, No. 6, pp. 442-453.RussiaImpact structure, Puchezh-Katun, Popigai, Diamond
DS1997-1003
1997
Scherer, T., Hafner, S.S., et al.Defects in natural diamonds depending on geological environmentProceedings 30th. I.G.C., Pt. 16, pp. 1-15.South Africa, Germany, RussiaDiamond morphology, Deposit - Finsch, Popigai
DS1997-1110
1997
Stoffler, D.Minerals in the deep earth: a message from the asteroid beltScience, Vol. 278, No. 5343, Nov. 28, pp. 1576-7MantleMineralogy, Impacts
DS1998-0657
1998
Iouchko, N.A., Kremenetsky, A.A., Kouznetsov, I.I.Nature of diamonds, melts and fluids in the ring structures: endogeneous explosion vs impact process.7th International Kimberlite Conference Abstract, pp. 342-5.Russia, Siberia, Yakutiavolcanism., Impact structures
DS1998-1232
1998
Rice, A.Can the blasting excavation engineering sciences provide insight into the processes of kimberlite erupt7th. Kimberlite Conference abstract, pp. 733.GlobalCrater, diatreme, Phreatomagmatic eruption
DS1998-1305
1998
Scott Smith, B.H., Orr, R.G., Robertshaw, P., Avery, R.Geology of the Fort a la Corne kimberlites, Saskatchewan #37th. Kimberlite Conference abstract, pp. 772-4.SaskatchewanClassification, Deposit - Fort a la Corne, crater, age, rock types
DS1999-0254
1999
Glikson, A.Y.Oceanic mega impacts and crustal evolutionGeology, Vol. 27, No. 5, May pp. 387-90.GlobalCraters, impacts, Gondwana, East African Rift
DS1999-0773
1999
Vishnevskii, S.A., Palchik, N.A., Raitala, J.Diamonds in impactites of the Lappajarvi impact craterRussian Geology and Geophysics, Vol. 40, No. 10, pp. 1487-90.FinlandImpact crater
DS2000-0002
2000
Abbott, D.H.Do large impacts strengthen mantle plumes and produce komatiites?Geological Society of America (GSA) Abstracts, Vol. 32, No. 7, p.A-314.MantleImpacts
DS2000-0686
2000
Morgan, J.V., Warner, M.R., Collins, G.S., Meloshm H, J.Peak ring formation in large impact craters: geophysical constraints from Chicxulub.Earth and Planetary Science Letters, Vol.183, No.3-4, pp. 347-54.CaliforniaImpact craters, Structure - ring dikes
DS2001-0270
2001
Dressler, B.O., Reimold, W.U.Terrestrial impact melt rocks and glassesEarth Science Reviews, Vol. 56, No. 1-4, pp. 205-84.GlobalImpact craters, ring basins, Review
DS2002-1635
2002
Valley, J.W., Peck, W.H., King, E.M., Wilde, S.A.A cool early EarthGeology, Vol. 30,4,Apr.pp.351-4.MantleArchean - geochronology, impacts, meteorites
DS2003-0855
2003
Macdonald, F.A., Bunting, J.A., Cina, S.E.Yarrabubba - a large deeply eroded impact structure in the Yilgarn Craton, WesternEarth and Planetary Science Letters, Vol. 213, No. 3-4, pp. 225-247.AustraliaImpact structure - not specific to diamonds
DS200412-1188
2003
Macdonald, F.A., Bunting, J.A., Cina, S.E.Yarrabubba - a large deeply eroded impact structure in the Yilgarn Craton, Western Australia.Earth and Planetary Science Letters, Vol. 213, no. 3-4, pp. 225-247.AustraliaImpact structure - not specific to diamonds
DS200412-1418
2004
Nelson, D.R.The early Earth.The Precambrian Earth, tempos and events, editors Eriksson, P.G., Altermann, W., Nelson, D.R., Mueller, W.U., Elsevier, Developments in Precambrian Geology No. 12, CMantleStratigraphic record, impact events
DS200612-0498
2006
Grieve, R.A.F., Cintala, M.J., Therriault, A.M.Large scale impacts and the evolution of the Earth's crust: the early years.Geological Society of America, Processes on the Earth, Special Paper 405, Chapter 2.MantleImpact processes
DS200612-1319
2006
Skinner, E.M.W., Marsh, J.S.The emplacement of class 1 kimberlites - part 2, petrographic evidence.Emplacement Workshop held September, 5p. abstractGlobalTransition zones - root, diatremes, crater
DS200612-1320
2006
Skinner, E.M.W., Marsh, J.S.The emplacement of class 1 kimberlites - part 1, evidence of geological features.Emplacement Workshop held September, 5p. abstractGlobalZones - root, diatremes, crater
DS200612-1582
2006
Zahnle, K.J.Earth's earliest atmosphere.Elements, Vol. 3, no. 4, August pp. 217-222.MantleEvolution, zircon, impacts
DS200712-0267
2007
Dorijnamjaa, D., Kondratov, L.S., Voinkov, D.M., Amarsaikhan, Ts.Specific gas composition of the absorbed form in impatites of the diamond bearing Mongolian astropipes.Plates, Plumes, and Paradigms, 1p. abstract p. A231.Asia, MongoliaAgit Khangay, Khuree Mandal Tsenkher, Bayan Khuree
DS200812-0693
2008
Lyukhin, A.M.The hypothesis of impact origin of diamonds and kimberlites.9IKC.com, 3p. extended abstractMantleImpact genesis
DS200912-0486
2009
McCall, G.J.H.Half a century of progress in research on terrestrial impact structure: a review.Earth Science Reviews, Vol. 92, 3-4, Feb. pp. 99-172.TechnologyImpact structures - review
DS200912-0572
2008
Pati, J.K., Reimold, W.U., Koeberl, C., Pati, P.The Dhala structure, Bundelk hand Craton, central India - eroded remnant of a lare Paleoproterozoic impact structure.Meteorites and Planetary Science, Vol. 43, pp. 1383-1398.IndiaImpact structure
DS201112-0196
2011
Collins, G.S., Elbeshausen, D., Davison, T.M., Robbins, S.J., Hynek, B.M.The size frequency distribution of ellipitical impact craters.Earth and Planetary Science Letters, Vol. 310, 1-2, pp. 1-8.GlobalImpact Crater
DS201112-0374
2011
Glikson, A.Y., Vickers, J.Asteroid impact connections of crustal evolution.Australian Journal of Earth Sciences, Vol.57, 1, pp. 79-95.MantleImpacts
DS201112-1004
2011
Stewart, S.A.Estimates of yet-to-find impact crater population on Earth.Journal of the Geological Society, Vol. 168, 1, pp. 1-14.GlobalImpact Crater
DS201212-0582
2012
Reimold, W.U, Jourdan, F.Impact! Bolides. Craters and catastrophes.Elements, Vol. 8, 1, Feb, pp. 19-24.GlobalImpact Crater
DS201212-0777
2012
Wiellicki, M.M., Harrison, T.M., Schmitt, A.K.Geochemical signatures and magmatic stability of terrestrial impact produced zircons.Earth and Planetary Science Letters, Vol. 321-322, pp. 20-31.MantleImpact structures
DS201312-0670
2012
Osinski, G.R., Pierazzo, E.Impact cratering: processes and products.Wiley Blackwell, 330p. Approx. $ 145.MantleCrater
DS201312-0686
2008
Pati, J.K., Reimold, W U., Koeberl, C., Pati, P.The Dhala structure, Bundelk hand craton, central India - eroded remnant of a large Paleoproterozoic impact structure.Meteorites and Planetary Science, Vol. 40, 8, pp. 1383-1398.IndiaImpact structure
DS201312-0724
2013
Quesnel, Y., Gattacceca, J., Osinski, G.R., Rochette, P.Origin of the central magnetic anomaly at the Haughton impact structure, Canada.Earth and Planetary Science Letters, Vol. 368, pp. 116-122.CanadaImpacts
DS201312-0888
2013
Sturm, S., Wulf, G., Jung, D., Kenmann, T.The Ries impact, a double layerGeology, Vol. 41, 5, pp. 531-534.Europe, GermanyImpact Crater
DS201412-0284
2014
Ghose, T.Comet strike to blame for Canada's iconic Sudbury Basin.Scientific American, 2p.Canada, OntarioImpacts
DS201412-0452
2014
Kenkmann, T., Poelchau, M.H., Wulf, G.Structural geology of impact craters.Journal of Structural Geology, Vol. 62, pp. 156-182.GlobalReview - impact cratering
DS201412-0516
2014
Litvin, Yu.A.The stishovite paradox in the genesis of superdeep diamonds.Doklady Earth Sciences, Vol. 455, 1, pp. 274-278.TechnologyImpact Crater
DS201412-0597
2014
Moskovitch, K.Mysterious Siberian crater attributed to methane.Nature, July 31, 2p.Russia, SiberiaCrater
DS201412-0731
2014
Reimold, W.U., Koeberl, C.Impact structures in Africa: a review.Journal of African Earth Sciences, Vol. 93, pp. 57-175.AfricaImpacts - review
DS201511-1839
2015
Hansen, V.L.Impact origin of Archean cratons.Lithosphere, Vol. 7, pp. 563-578,MantleImpacts

Abstract: Earth was a completely different planet more than 2.5 billion years ago. Little is known about this critical time when cratonic continental seeds formed; life emerged; and precious mineral resources concentrated. Our knowledge is limited because plate tectonic processes destroyed most of this early record. In contrast, Earth's sister, Venus -- similar in size, density, bulk composition, and distance from the Sun -- never developed plate tectonics. Venus also lacks a water cycle. Like siblings, Venus and Earth were most similar in their youth; however, Venus preserves a more complete geological record of its infancy, including both exogenic and endogenic features. Applying clues from Venus, Vicky L. Hansen proposes a new hypothesis for the formation of Earth's cratons. Large bolides pierced early thin lithosphere causing massive partial melting in the ductile mantle; melt escaped upward, forming cratonic crust; meanwhile strong, dry, buoyant melt residue formed cratonic roots, serving as unique buoyant life preservers during future plate-tectonic recycling.
DS201702-0234
2016
Presser, J.L.B., Farina-Dolsa, S., Larroza-Cristaldo, F.A., Rocca, M., Alonso, R.N., Acededo, R.D., Cabral-Antunez, N.D., Baller, L., Zarza-Lima, P.R., Sekatcheff, J.M.Modeled mega impact structures in Paraguay: II the eastern region. **PortBoletin del Museo Nacional de Historia Narural del Paraguay, Vol. 20, 2, pp. 205-213. pdf available in * PortSouth America, ParaguayImpact Crater

Abstract: We report here the discovery and study of several new modeled large impact craters in Eastern Paraguay, South America. They were studied by geophysical information (gravimetry, magnetism), field geology and also by microscopic petrography. Clear evidences of shock metamorphic effects were found (e.g., diaplectic glasses, PF, PDF in quartz and feldspar) at 4 of the modeled craters: 1) Negla: diameter:~80-81 km., 2) Yasuka Renda D:~96 km., 3) Tapyta, D: ~80 km. and 4) San Miguel, D: 130-136 km. 5) Curuguaty, D: ~110 km. was detected and studied only by geophysical information. Target-rocks range goes from the crystalline Archaic basement to Permian sediments. The modeled craters were in some cases cut by tholeiitic/alkaline rocks of Mesozoic age and partially covered by lavas of the basaltic Mesozoic flows (Negla, Yasuka Renda, Tapyta and Curuguaty). One of them was covered in part by sediments of Grupo Caacupé (age: Silurian/Devonian). Some of these modeled craters show gold, diamonds, uranium and REE mineral deposits associated. All new modeled large impact craters are partially to markedly eroded.
DS201709-1980
2011
Dorjnamjaa, D., Voinkov, D.M., Kondratov, L.S., Selenge, D., Altanshagai, G., Enkhbatar, B.Concerning diamond and gold bearing astropipes of Mongolia.International Journal of Astronomy and Astrophysics, Vol. 1, pp. 98-104.Asia, Mongoliaastropipes, impact craters

Abstract: In this paper we present summation of eighteen year’s investigation of the all gold and diamond-bearing astropipes of Mongolia. Four astropipe structures are exemplified by the Agit Khangay (10 km in diameter, 470 38' N; 960 05' E), Khuree Mandal (D=11 km; 460 28' N; 980 25' E), Bayan Khuree (D=1 km; 440 06' N; 1090 36' E), and Tsenkher (D=7 km; 980 21' N; 430 36' E) astropipes of Mongolia. Detailed geological and gas-geochemical investigation of the astropipe structures show that diamond genesis is an expression of collision of the lithospheric mantle with the explosion process initiated in an impact collapse meteor crater. The term "astropipes" (Dorjnamjaa et al., 2010, 2011) is a neologism and new scientific discovery in Earth science and these structures are unique in certain aspects. The Mongolian astropipes are genuine "meteorite crater" structures but they also contain kimberlite diamonds and gold. Suevite-like rocks from the astropipes contain such minerals, as olivine, coesite, moissanite (0,6 mm), stishovite, coesite, kamacite,tektite, khamaravaevite (mineral of meteorite titanic carbon), graphite-2H, khondrite, picroilmenite, pyrope, phlogopite, khangaite (tektite glass, 1,0-3,0 mm in size), etc. Most panned samples and hand specimens contain fine diamonds with octahedrol habit (0, 2-2,19 mm, 6,4 mg or 0,034-0,1 carat) and gold (0,1-5 g/t). Of special interest is the large amount of the black magnetic balls (0,05-5,0 mm) are characterized by high content of Ti, Fe, Co, Ni, Cu, Mn, Mg, Cd, Ga, Cl, Al, Si, K. Meanwhile, shatter cones (size approx. 1.0 m) which are known from many meteorite craters on the Earth as being typical of impact craters were first described by us Khuree Mandal and Tsenkher astropipe structures. All the described meteorite craters posses reliable topographic, geological, mineralogical, geochemical, and aerospace mapping data, also some geophysical and petrological features (especially shock metamorphism) have been found, all of which indicate that these structures are a proven new type of gold-diamond-bearing impact structure, termed here "astropipes". The essence of the phenomenon is mantle manifestation and plume of a combined nuclear-magma-palingenesis interaction.
DS201802-0239
2018
Glikson, A.Structure and origin of Australian ring and dome features with reference to the search for asteroid impact events.Tectonophysics, Vol. 722, pp. 175-196.Australiaring structures

Abstract: Ring, dome and crater features on the Australian continent and shelf include (A) 38 structures of confirmed or probable asteroid and meteorite impact origin and (B) numerous buried and exposed ring, dome and crater features of undefined origin. A large number of the latter include structural and geophysical elements consistent with impact structures, pending test by field investigations and/or drilling. This paper documents and briefly describes 43 ring and dome features with the aim of appraising their similarities and differences from those of impact structures. Discrimination between impact structures and igneous plugs, volcanic caldera and salt domes require field work and/or drilling. Where crater-like morphological patterns intersect pre-existing linear structural features and contain central morphological highs and unique thrust and fault patterns an impact connection needs to tested in the field. Hints of potential buried impact structures may be furnished by single or multi-ring TMI patterns, circular TMI quiet zones, corresponding gravity patterns, low velocity and non-reflective seismic zones. A) Examples of crater-form and dome-form features containing elements consistent with an impact origin, though unproven, include Auvergne, Delamere, Fiery Creek, Monte Christo, Mount Moffatt, Tanami East, Youngerina, and Tingha. B) Examples of buried multi-ring features of possible to probable impact origin include Augathella, Balfour Downs, Calvert Hills, Camooweal, Green Swamp Well, Herbert, Ikybon River, Ilkurka, Lennis, McLarty Hills, Mount Davies, Mulkara; Neale; Sheridan Creek, Oodjuongari and Renehan. C) Examples of igneous plugs unrelated to impacts include the Monto gabbro and numerous circular granitoid plugs such as Windinie Hills granite and Yataga granodiorite. D) Large circular structures such as Mount Ashmore and Gnargoo are considered to have convincing structural deformation features warranting classification as probable impact structures. The origin of very large circular TMI and gravity patterns such as of the Diamantina River drainage feature, Coonamona anomaly and the multiple TMI ring pattern of the Deniliquin-Booligal remain unresolved. The advent of ~ 40 m TMI grid coverage promises to further uncover ring and dome features, such as the McLarty Hills multi-ring feature, potentially increasing the inventory of ring structures on the Australian continent. Compared with frequency distribution patterns of extra-terrestrial impact structures worldwide, the Australian record displays a relatively common occurrence of large impact structures and relative depletion in small impact structures and craters. This is explained by the better preservation of large structures at deep crustal zones as compared to the erosion of small craters.
DS201802-0259
2017
Presser, J.L.B., Alonso, R.N., Farina Dolsa, S., Larroza, F.A., Rocca, M.C.L., Hornes, K., Baller, L.Impact metamorphism evidence of Negla and Yasuka Renda large impact crater. ***PORT only abstract in eng Boletin Museum History Natural Paraguay ***IN PORT, Vol. 21, no. 2, pp. 69-82. pdfSouth America, Paraguayimpact craters
DS201811-2561
2018
Cox, M.A., Cavosie, A.J., Bland, P.A., Miljkovic, K., Wingate, M.T.D.Microstructural dynamics of central uplifts: reidite offset by zircon twins at the Woodleigh impact structure, Australia.Geology, doi.org/10.1130/G45127.1 4p.Australiacrater

Abstract: Impact cratering is a dynamic process that is violent and fast. Quantifying processes that accommodate deformation at different scales during central uplift formation in complex impact structures is therefore a challenging task. The ability to correlate mineral deformation at the microscale with macroscale processes provides a critical link in helping to constrain extreme crustal behavior during meteorite impact. Here we describe the first high-pressure-phase-calibrated chronology of shock progression in zircon from a central uplift. We report both shock twins and reidite, the high-pressure ZrSiO4 polymorph, in zircon from shocked granitic gneiss drilled from the center of the >60-km-diameter Woodleigh impact structure in Western Australia. The key observation is that in zircon grains that contain reidite, which forms at >30 GPa during the crater compression stage, the reidite domains are systematically offset by later-formed shock deformation twins (?20 GPa) along extensional planar microstructures. The {112} twins are interpreted to record crustal extension and uplift caused by the rarefaction wave during crater excavation. These results provide the first physical evidence that relates the formation sequence of both a high-pressure phase and a diagnostic shock microstructure in zircon to different cratering stages with unique stress regimes that are predicted by theoretical and numerical models. These microstructural observations thus provide new insight into central uplift formation, one of the least-understood processes during complex impact crater formation, which can produce many kilometers of vertically uplifted bedrock in seconds.
DS201901-0051
2019
Ovsyuk, N.N., Goryainov, S.V., Likhacheva, A.Y.Raman scattering of impact diamonds. LonsdaleiteDiamond & Related Materials, Vol. 91, pp. 207-212.Russia, SiberiaPopigai

Abstract: We report the results of a study of the polycrystalline powder of the diamond-lonsdaleite from the Popigai crater (Siberia) using UV micro-Raman spectroscopy and high-resolution synchrotron X-ray diffraction. By subtracting two experimental Raman spectra of diamond-lonsdaleite samples with close amounts of diamond and lonsdaleite, we were able to identify the polytypic composition of impact diamonds in contrast to the method of X-ray diffraction. We have managed to get for the first time the spectrum of “pure” lonsdaleite. Its deconvolution has allowed us to identify all the three Raman - active vibrational modes E2g, A1g, and E1g whose positions agree well with the results of ab initio calculations.
DS201902-0268
2018
Demarco, E.Erosion has erased most of Earth's impact craters. Here are the survivors. History and list of craters.sciencenews.org, Dec. 18, 5p.Europe, Greenlandcrater
DS201902-0274
2019
Grewal, D.S., Dasgupta, R., Sun, C., Tsuno, K., Costin, G.Delivery of carbon, nitrogen, and sulfur to the silicate Earth by a giant impact.Science Advances, Vol. 5, 1, Jan. 23, 10.1126/sciadv.aau3669 13p.Mantlecrater

Abstract: Earth’s status as the only life-sustaining planet is a result of the timing and delivery mechanism of carbon (C), nitrogen (N), sulfur (S), and hydrogen (H). On the basis of their isotopic signatures, terrestrial volatiles are thought to have derived from carbonaceous chondrites, while the isotopic compositions of nonvolatile major and trace elements suggest that enstatite chondrite-like materials are the primary building blocks of Earth. However, the C/N ratio of the bulk silicate Earth (BSE) is superchondritic, which rules out volatile delivery by a chondritic late veneer. In addition, if delivered during the main phase of Earth’s accretion, then, owing to the greater siderophile (metal loving) nature of C relative to N, core formation should have left behind a subchondritic C/N ratio in the BSE. Here, we present high pressure-temperature experiments to constrain the fate of mixed C-N-S volatiles during core-mantle segregation in the planetary embryo magma oceans and show that C becomes much less siderophile in N-bearing and S-rich alloys, while the siderophile character of N remains largely unaffected in the presence of S. Using the new data and inverse Monte Carlo simulations, we show that the impact of a Mars-sized planet, having minimal contributions from carbonaceous chondrite-like material and coinciding with the Moon-forming event, can be the source of major volatiles in the BSE.
DS201902-0311
2018
Reudas, T., Breuer, D.Isocrater impacts: conditions and mantle dynamical responses for different impactor types.Icarus, Vol. 306, 1, pp. 94-115.Mantleimpact craters

Abstract: Impactors of different types and sizes can produce a final crater of the same diameter on a planet under certain conditions. We derive the condition for such “isocrater impacts” from scaling laws, as well as relations that describe how the different impactors affect the interior of the target planet; these relations are also valid for impacts that are too small to affect the mantle. The analysis reveals that in a given isocrater impact, asteroidal impactors produce anomalies in the interior of smaller spatial extent than cometary or similar impactors. The differences in the interior could be useful for characterizing the projectile that formed a given crater on the basis of geophysical observations and potentially offer a possibility to help constrain the demographics of the ancient impactor population. A series of numerical models of basin-forming impacts on Mercury, Venus, the Moon, and Mars illustrates the dynamical effects of the different impactor types on different planets. It shows that the signature of large impacts may be preserved to the present in Mars, the Moon, and Mercury, where convection is less vigorous and much of the anomaly merges with the growing lid. On the other hand, their signature will long have been destroyed in Venus, whose vigorous convection and recurring lithospheric instabilities obliterate larger coherent anomalies.
DS201908-1797
2019
Murri, M., Smith, R.L., McColl, K., Hart, M., Alvaro, M., Jones, A.P., Nemeth, P., Salzmann, C.G., Cora, F., Domeneghetti, M.C., Nestola, F., Sobolev, N.V., Vishnevsky, S.A., Logvinova, A.M., McMillan, P.F.Quantifying hexagonal stacking in diamond. ( lonsdaleite)Nature Scientific Reports, doi.org/10.1038/ s41598-019-46556-3 8p. PdfGlobaldiamond morphology, impact craters

Abstract: Diamond is a material of immense technological importance and an ancient signifier for wealth and societal status. In geology, diamond forms as part of the deep carbon cycle and typically displays a highly ordered cubic crystal structure. Impact diamonds, however, often exhibit structural disorder in the form of complex combinations of cubic and hexagonal stacking motifs. The structural characterization of such diamonds remains a challenge. Here, impact diamonds from the Popigai crater were characterized with a range of techniques. Using the MCDIFFaX approach for analysing X-ray diffraction data, hexagonality indices up to 40% were found. The effects of increasing amounts of hexagonal stacking on the Raman spectra of diamond were investigated computationally and found to be in excellent agreement with trends in the experimental spectra. Electron microscopy revealed nanoscale twinning within the cubic diamond structure. Our analyses lead us to propose a systematic protocol for assigning specific hexagonality attributes to the mineral designated as lonsdaleite among natural and synthetic samples.
DS201908-1804
2019
Presser, J.B.L., Alonso, R., Rocca, M.Malvinas Islands ( Falkland Islands): advances in the inferred buried marine impact mega-structure.Researchgate, July 27p. PdfFalkland Islandsimpact structure

Abstract: In 1992 Rampino noticed a large, almost circular negative gravity anomaly (~30 mGal) on the Falkland Plateau to the WNW of Malvinas Islands/Falklnad Islands using satellite data then available, and speculated that it might be associated with a large (~250 km wide?) buried impact structure. In some more recent compilations Rocca & Presser (2015) and Rocca et al. (2017) was attended the Malvinas Islands/Falklnad Islands “buried impact structure” with particular care; but also these works was harshly criticized. The present text, which is an advance to demonstrate the certain possibilities that this Malvinas Islands/Falklnad Islands It could really be a very probable mega impact structure, gathers shows and evaluates the existing and available indirect information; like gravimetry (Isostasy, Free-air and Bouguer); seismic reflection (Geco Prakla); and, even commenting aspects of its magnetic behavior and its local geology. In all gravimetric analyses from the Malvinas Islands/Falklnad Islands “buried impact structure” it can be shown that an annulus of positive gravity anomaly surrounding a circular oval depression of negative (isostasy and Free-air)/much lower (Bouguer) values gravity anomaly. The most relevant gravimetric information would be the near circular to oval Bouguer gravity low anomaly (with a minimum value of ~150 mGal) surrounded by at least circular ~255 kilometers wide circular ring of positive gravity anomaly (maximum ~225 mGal); a very high values of Bouguer anomaly that are highly compatible with what is expected to be found in mega impact structures. The Malvinas probable impact structure shows almost 100 mGal superior to the volcanic complex of Iceland; so it seems obvious that Malvinas probable impact structure moves away from a speculation by mega-paleo-volcano origin. When gravimetrically modeled, a probable peak ring of ~255 km is evidenced; as well as, the inferred the ~550 km probable rim-crest; configuration that reproduces an almost perfect and symmetrical modeling of a very probable giant impact structure with its clear visible the very probable elements: rim crest-annulus basin-peak ring-central basin-peak ring-annulus basin-rim crest. Four Geco Prakla seismic reflection lines on the area located to the SW of the potential peak ring show a vertical and disturbed crystalline basement (the “peak ring”); in three of them, the “central basin” what would it be filled with sediments after impact (probable ejecta). Using the empirical formula of Assumpção et al. (2013) calculation for crustal thickness could be found very clearly strong CT distortion along Malvinas very probable giant impact structure: around 3400-4000 meters; as is to be expected in terrestrial mega impact structure. Harness the EMAG2v3 a global Earth Magnetic Anomaly Grid compiled from satellite (Meyer et al., 2017) for the Malvinas very probable giant impact structure a well superior anomaly was found and better definition than observed, using the same information, to the one characterized by the impact crater Chicxulub. The geological map of the Falkland Islands Government that was placed on top of the modeling isostasy gravimetric map where the approximate circumference of the very probable peak-ring and the very probable rim-crest is highlighted. This information allows to see that the largest island (West Malvinas) would be part of the very probable peak-ring and the smaller island (East Malvinas) would be part of the very probable rim-crest; both separated by the depression that would correspond to the very probable annulus basin. Based on what was analyzed in the Malvinas Islands area, we concluded the Malvinas exhibited geophysics traits of a large ancient asteroid impact; i.e. Malvinas very probable giant impact structure. Very probable impact structure what could be among one of the world's largest impact crater.
DS201910-2263
2019
Hand, E.World's oldest impact crater dated in Australian outback. YarrabubbaScience, Vol. 365, 6456, pp. 852-853.Australiaimpact crater

Abstract: In the outback of Western Australia, researchers have shown that shocked rocks were forged 2.229 billion years ago, when an asteroid crashed into our planet. The finding makes Yarrabubba crater, the 70-kilometer-wide scar left by the collision, Earth's oldest. The geologists who reported the date last week, at the Goldschmidt geochemistry conference, also point out a conspicuous coincidence: The impact came at the tail end of a planetwide deep freeze known as Snowball Earth. They say the impact may have helped thaw Earth by vaporizing thick ice sheets and lofting steam into the stratosphere, creating a powerful greenhouse effect. Other researchers are skeptical that Yarrabubba—which is just one-third the size of the crater left by the dinosaur-killing impact 66 million years ago—could have had such a profound effect on the climate. Still, they say, paleoclimate studies should consider the possible role of such violent collisions.
DS201910-2300
2019
Simms, M.J., Emston, K.A reassessment of the proposed "Lairg impact structure" and its potential implications for the deep structure of northern Scotland.Journal of the Geological Society, Vol. 76, pp. 817-829.Europe, Scotlandimpact crater

Abstract: The Lairg Gravity Low may represent a buried impact crater c. 40 km across that was the source of the 1.2 Ga Stac Fada Member ejecta deposit but the gravity anomaly is too large to represent a simple crater and there is no evidence of a central peak. Reanalysis of the point Bouguer gravity data reveals a ring of positive anomalies around the central low, suggesting that it might represent the eroded central part of a larger complex crater. The inner or peak rings of complex craters show a broadly consistent 2:1 relationship between ring diameter and total crater diameter, implying that the putative Lairg crater may be as much as 100 km across. This would place the crater rim within a few kilometres of the Stac Fada Member outcrop, a location inconsistent with the thickness and clast size of the ejecta deposit. We propose that the putative impact crater originally lay further east, substantially further from the Stac Fada Member than today, and was translocated westwards to its present location beneath Lairg during the Caledonian Orogeny. This model requires that a deep-seated thrust fault, analogous to the Flannan and Outer Isles thrusts, exists beneath the Moine Thrust in north-central Scotland.
DS201911-2554
2019
Presser, J.L.B., Alonso, R., Rocca, M.Malvinas Islands ( Falkland Islands): advances in the inferred buried marine impact mega-structure.Pyroclastic Flow Journal of Geology, Vol. 9, no. 1, pp. 1-14. pdf.Antarcticaimpact structure

Abstract: In 1992 Rampino noticed a large, almost circular negative gravity anomaly (~30 mGal) on the Falkland Plateau to the WNW of Malvinas Islands/Falkland Islands using satellite data then available, and speculated that it might be associated with a large (~250 km wide?) buried impact structure. In some more recent compilations Rocca & Presser (2015) and Rocca et al. (2017) was attended the Malvinas Islands/Falkland Islands “buried impact structure” with particular care; but also these works was harshly criticized. The present text, which is an advance to demonstrate the certain possibilities that this Malvinas Islands/Falklnad Islands It could really be a very probable mega impact structure, gathers shows and evaluates the existing and available indirect information; like gravimetry (Isostasy, Free-air and Bouguer); seismic reflection (Geco Prakla); and, even commenting aspects of its magnetic behavior and its local geology. In all gravimetric analyses from the Malvinas Islands/Falklnad Islands “buried impact structure” it can be shown that an annulus of positive gravity anomaly surrounding a circular oval depression of negative (isostasy and Free-air)/much lower (Bouguer) values gravity anomaly. The most relevant gravimetric information would be the near circular to oval Bouguer gravity low anomaly (with a minimum value of ~150 mGal) surrounded by at least circular ~255 kilometers wide circular ring of positive gravity anomaly (maximum ~225 mGal); a very high values of Bouguer anomaly that are highly compatible with what is expected to be found in mega impact structures. The Malvinas probable impact structure shows almost 100 mGal superior to the volcanic complex of Iceland; so it seems obvious that Malvinas probable impact structure moves away from a speculation by mega-paleo-volcano origin. When gravimetrically modeled, a probable peak ring of ~255 km is evidenced; as well as, the inferred the ~550 km probable rim-crest; configuration that reproduces an almost perfect and symmetrical modeling of a very probable giant impact structure with its clear visible the very probable elements: rim crest-annulus basin-peak ring-central basin-peak ring-annulus basin-rim crest. Four Geco Prakla seismic reflection lines on the area located to the SW of the potential peak ring show a vertical and disturbed crystalline basement (the “peak ring”); in three of them, the “central basin” what would it be filled with sediments after impact (probable ejecta). Using the empirical formula of Assumpção et al. (2013) calculation for crustal thickness could be found very clearly strong CT distortion along Malvinas very probable giant impact structure: around 3400-4000 meters; as is to be expected in terrestrial mega impact structure. Harness the EMAG2v3 a global Earth Magnetic Anomaly Grid compiled from satellite (Meyer et al., 2017) for the Malvinas very probable giant impact structure a well superior anomaly was found and better definition than observed, using the same information, to the one characterized by the impact crater Chicxulub. The geological map of the Falkland Islands Government that was placed ontop of the modeling isostasy gravimetric map where the approximate circumference of the very probable peak-ring and the very probable rim-crest is highlighted. This information allows to see that the largest island (West Malvinas) would be part of the very probable peak-ring and the smaller island (East Malvinas) would be part of the very probable rim-crest; both separated by the depression that would correspond to the very probable annulus basin. Based on what was analyzed in the Malvinas Islands area, we concluded the Malvinas exhibited geophysics traits of a large ancient asteroid impact; i.e. Malvinas very probable giant impact structure. Very probable impact structure what could be among one of the world's largest impact crater.
DS202002-0221
2020
Yelisseyev, A., Gromilov, S., Afanasiev, V., Sildos, I., Kiisk, V.Effect of lonsdaleite on the optical properties of impact diamonds.Diamonds & Related Materials, Vol. 101, 107640, 13p. PdfRussiaPopigai

Abstract: The special features of impact diamonds are the orientation of the nanosized grains relative to each other, the presence of hexagonal diamond (lonsdaleite, L) in a large part of the samples and the increased wear resistance. Using Raman spectroscopy and XRD, two groups of translucent samples of Popigai impact diamonds (PIDs) were selected: with and without lonsdaleite and the effect of lonsdaleite on the optical properties of the samples was studied. In all L-containing PIDs there is a strong absorption band of about 1230 cm-1 in the one-phonon region, in the mid-IR. The absorption edge is blurred and described by the Urbach rule. The estimated value of Eg ~4 eV for L is consistent with the first principles calculations. Impurity nitrogen is found only in L-free PIDs: There are signals from nitrogen-vacancy complexes in the photoluminescence (PL) spectra. Variations in the number of nitrogen atoms (N = 1 to 4) in the structure of these centers indicate significant variations in the parameters of PID annealing. L-containing PIDs are characterized by large strains in the lattice and, as a consequence, there are problems with the defect diffusion. The narrow lines in PL spectra, uncommon for diamond, can be the result of several orders of magnitude higher concentrations of impurities in PIDs formed during the solid-phase transition. The broadened peaks of 180, 278 and 383 K are distinguishable in the curves of thermostimulated luminescence (TSL) for L-free PIDs, but in the presence of L the TSL glow becomes continuous as in natural IaA-type diamonds with platelets. In general, lonsdaleite deteriorates the optical properties of impact diamonds and makes it difficult to create certain types of impurity-vacancy complexes for different applications.
DS202104-0607
2021
Shumilova, T.Diamond fossils as an important new key for astrobiology.Researchgate conference paper, 2p. PdfRussiaimpact craters Kara, Popigai

Abstract: Astrobiology is one of the actively studied fields aimed to answer the question about the Earth life origin. The detail studies of the organic matter could give a key for understanding about possible conditions for preservation of the biological material at the extreme conditions of the giant impact events and meteorite fallings. In the context of the astrobiological problem the recent discovery of diamond fossils is very informative and impressive [1, 2]. Here we describe in short the features of the impact-preserved organic relicts in the diamond state having relict fragments of cellulose and lignin, pointing to possibility to save organics even under the conditions of diamond formation. Impact Diamonds: Almost 50 years have passed since the discovery of impact diamonds. Currently, several varieties of impact diamonds are known in natural geological objects, determined by the type of carbon precursor, that define their formation mechanisms and structural features. Actually, aftergraphite, after-coal and after-organic diamonds are known [1-5]. The latter usually present in the form of diamond fossils after plant fragments. After-Graphitic Impact Diamonds: The aftergraphitic diamonds were discovered in the 70s of the XX century in the largest Popigai astrobleme with a diameter of about 100 km, bearing giant reserves of valuable technical diamond raw materials [3, 4]. This type of impact diamonds is formed by solid-state transformation of the graphite precursor structure to diamond with a diffusion-free mechanism forming micropolycrystalline aggregates with submicrometersized crystals [1]. This variety is characterized by polyphase aggregates with possible substantial amount of hexagonal packaging defects (named “lonsdaleite”) within the cubic diamond structure [6]. It may also include an admixture of relict graphite, amorphous and onion-like carbon [7, 8]. Currently, apographic diamonds have been discovered in several deposits, for example diamond-rich Popigai and Puchezh-Katunki in Russia, Ries (Germany), Sudbury (Canada). After-Coal Impact Diamonds: After-coal impact diamonds were discovered a bit later, they were found in the giant Kara astrobleme in 80s of the XX century [3, 4]. This diamond type was formed by short-distance diffusion mechanism from coalificated carboniferous particles from the host sedimentary rocks, described in detail in [5]. The diamonds have crystallites size about 20-50 nm, differ from the after-graphitic variety by presence of ideal octahedral crystallite shapes and dislocation-free (lonsdaleite-free) structure [2]. By present the after-coal diamonds are known only at the Kara astrobleme and near-set Ust`-Kara impactites. After-Organic Diamonds (Diamond Fossils): The diamond fossils have been just discovered. The first find has been found out within melt fragment within suevitic breccia at the Kara astrobleme (Fig. 1). The diamonds are presented with well preserved relict cell micromorphology and have very specific structure, composition and spectroscopic features studied and described in detail in [1].
DS202104-0607
2021
Shumilova, T.Diamond fossils as an important new key for astrobiology.Researchgate conference paper, 2p. PdfRussiaimpact craters Kara, Popigai

Abstract: Astrobiology is one of the actively studied fields aimed to answer the question about the Earth life origin. The detail studies of the organic matter could give a key for understanding about possible conditions for preservation of the biological material at the extreme conditions of the giant impact events and meteorite fallings. In the context of the astrobiological problem the recent discovery of diamond fossils is very informative and impressive [1, 2]. Here we describe in short the features of the impact-preserved organic relicts in the diamond state having relict fragments of cellulose and lignin, pointing to possibility to save organics even under the conditions of diamond formation. Impact Diamonds: Almost 50 years have passed since the discovery of impact diamonds. Currently, several varieties of impact diamonds are known in natural geological objects, determined by the type of carbon precursor, that define their formation mechanisms and structural features. Actually, aftergraphite, after-coal and after-organic diamonds are known [1-5]. The latter usually present in the form of diamond fossils after plant fragments. After-Graphitic Impact Diamonds: The aftergraphitic diamonds were discovered in the 70s of the XX century in the largest Popigai astrobleme with a diameter of about 100 km, bearing giant reserves of valuable technical diamond raw materials [3, 4]. This type of impact diamonds is formed by solid-state transformation of the graphite precursor structure to diamond with a diffusion-free mechanism forming micropolycrystalline aggregates with submicrometersized crystals [1]. This variety is characterized by polyphase aggregates with possible substantial amount of hexagonal packaging defects (named “lonsdaleite”) within the cubic diamond structure [6]. It may also include an admixture of relict graphite, amorphous and onion-like carbon [7, 8]. Currently, apographic diamonds have been discovered in several deposits, for example diamond-rich Popigai and Puchezh-Katunki in Russia, Ries (Germany), Sudbury (Canada). After-Coal Impact Diamonds: After-coal impact diamonds were discovered a bit later, they were found in the giant Kara astrobleme in 80s of the XX century [3, 4]. This diamond type was formed by short-distance diffusion mechanism from coalificated carboniferous particles from the host sedimentary rocks, described in detail in [5]. The diamonds have crystallites size about 20-50 nm, differ from the after-graphitic variety by presence of ideal octahedral crystallite shapes and dislocation-free (lonsdaleite-free) structure [2]. By present the after-coal diamonds are known only at the Kara astrobleme and near-set Ust`-Kara impactites. After-Organic Diamonds (Diamond Fossils): The diamond fossils have been just discovered. The first find has been found out within melt fragment within suevitic breccia at the Kara astrobleme (Fig. 1). The diamonds are presented with well preserved relict cell micromorphology and have very specific structure, composition and spectroscopic features studied and described in detail in [1].

 
 

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