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Ukrainian Asteroid Impact Craters could be part of explaining Dinosaur extinction around 65 millions of years ago

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Ukrainian Asteroid Impact Craters could be part of explaining Dinosaur extinction around 65 millions of years ago

Ukrainian Asteroid Impact Craters could be part of explaining Dinosaur extinction around 65 millions of years ago.

Several impact craters are found in Ukraine, however their age ranges from 350 to 65 million years old. So these craters are evidence of older asteroid impacts hitting the earth long time ago. However, these craters plays an important role in understanding the frequencies of asteroid impacts to earth, as well as understanding the critical K/T boundary and associated layers in our geological history.

At least two of the identified impact craters in Ukraine seem to be linked to the age of mass extinction on earth happened around 65 million years ago. This is the age of the K/T boundary found around the world as well.

We will now discuss some of the craters, and begins with the best described of them, the Boltysh Impact Crater.

The Boltysh Crater is an impact crater in the Kirovohrad Oblast province of Ukraine.

The crater is 24 km in diameter and its age of 65.17 ± 0.64 million years, based on argon dating techniques, is within error of that of Chicxulub Crater in Mexico, and the KT boundary. The Chicxulub impact is believed to have caused the mass extinction at the end of the Cretaceous era, which included the extinction of the dinosaurs.

As well as Boltysh, several other impact craters around the world have estimated ages of about 65 million years, leading to the suggestion that the Earth was struck by multiple asteroid impacts at that time. The collision of Comet Shoemaker-Levy 9 with Jupiter in 1994 showed that such multiple impacts over a few days are possible.

Boltysh Crater is located in central Ukraine, in the basin of the Tiasmyn River, a tributary of the Dnieper River. It is 24 km in diameter, and is surrounded by an eject blanket of breccia preserved over an area of 6500 km². It is estimated that immediately after the impact, ejecta covered an area of 25,000 km² to a depth of 1 m or greater, and was some 600 m deep at the crater rim. The crater is not visible on satellite pictures as it is part of agricultural land today and covered with sediments.

The crater contains a central uplift about 6 km in diameter, rising about 550 m above the base level of the crater. This uplift currently lies beneath about 500 m of sediment deposited since the impact, and was discovered in the 1960s during oil exploration.

When first identified, the age of the crater could only be roughly constrained between the age of the impacted rocks (the target) and the age of overlying sediments. The target rocks date from the Cenomanian (98.9 to 93.5 million years ago) and Turonian (93.5 to 89 million years ago) epochs. Bore samples of sediments overlying the crater contain fossils dating from the Paleocene epoch, 65 to 54.8 million years ago. The age of the crater was thus constrained to between 54.8 and 98.9 million years.

Subsequent radiometric dating reduced the uncertainty. The concentration of uranium-238 decay products in impact glasses from the crater were used to derive an age of 65.04 ± 1.10 million years. Analysis of argon radioactive decay products yielded an age of 65.17 ± 0.64 million years. These ages are similar to that of Chicxulub Crater.

Although the ages derived for Chicxulub and Boltysh are the same to within their statistical errors, it does not necessarily follow that they formed at exactly the same time. At the estimated rate of impacts on the Earth, it would not be extremely unusual for a Boltysh-sized crater to be formed within half a million years of Chicxulub. The dating of these impact craters is not yet accurate enough to establish whether the asteroids arrived thousands of years apart, perhaps as part of a generally elevated rate of impacts at that time, or were almost simultaneous, like the impacts of the fragments of Comet Shoemaker-Levy 9 on Jupiter in 1994.

The discovery of the unconfirmed Silverpit crater and the early report of its age as 65 – 60 million years initially gave greater weight to the hypothesis that the Earth was struck by multiple asteroids at this time, however, the age estimate has now been broadened to 74 – 45 million years.

The controversial Shiva crater is claimed to have formed around the same time, but its status as an impact crater is disputed.

CEPSAR One hundred and two core boxes containing over 400m of core from the Bolytsh impact crater in the Ukraine have arrived in Aberdeen as part of the NERC funded project into the environmental effects that resulted from this 65 million year old impact crater. CEPSAR scientists Dr Jon Watson, Prof. Simon Kelley and Dr Iain Gilmour joined their University of Aberdeen colleague Dave Jolley for an exciting day doing an initial sampling of the core. Core recovery is over 95% providing the team with a near complete geological record starting from the impact rocks of the crater floor through nearly 400m of sediments from the lake that filled the crater after the impact.

The initial sampling comprised some 200 samples that will form part of the detailed geochemical and palynological examination that the team will be undertaking in the coming months. The project is examining the possibility for several impacts at the 65 million year old Cretaceous-Tertiary boundary and their separate and combined consequences for life on Earth at the time.

Another impact crater north of the Bolytsh impact crater is the Rotmistrovka crater with a diameter of approximately 2.7 kilometers and is assumed to be of 120 +/- 10 million years old. So this crater is of a much older date and is not part of the potential mass extinction multiple impact scenario around 65 million years ago which Bolytsh impact crater seems to belong to.

Seleny Gai impact crater just south of the Bolytsh crater is of 80 million +/- 20 million years old, so it could be part of the multiple impact event where Bolytsh belongs.

Ilyinets impact crater with a diameter of 8.5 kilometers and an age of 378 +/- 5 million years is located some 230 kilometers west of Bolytsch crater. This crater is not exposed to surface today.

Around 70 kilometers north of Ilyinets crater we find the Zapadnaya Impact Crater with a diameter of 3.2 kilomters. The age of this crater is estimated to 165 +/- million years. Also this crater is not exposed to the surface today.

If you have further interest in knowing more about impact craters around the world, The Earth Impact Database could be a good place for you to start learning more about where these are.

Lots have been written about the Bolytsh impact crater and here is a reference list for you to dig into if you want.

1. Bass, Yu B., Galaka, A.I. and Grabovskiy,V.I., The Boltysh oil shales (in Russian). Razvadka i Okhrana Nedr, pp. 11-15. 1967.

2. Boiko, A. K., Val’ter, A.A. and Vishnyak,M.M., On the age of the Boltysh depression (in Russian). Geologicheskii Zhurnal, v. 45, pp. 86-90. 1985.

3. Cockell, C. S., Lee, P., The Biology of Impact Craters – a review. Biol. Rev., 77, P. 279 – 310. 2002.

4. Dabizha, A. I., Fedynsky, V. V., Features of the gravitational field of astroblemes (in Russian). Meteoritika, v. 36, pp. 113-120. 1977.

5. Dabizha, A. I., Krass, M. S., The evolution of explosive meteorite craters on Earth (in Russian). “Zemlya i Vselennaya”, v. 5, pp. 80-88. 1975.

6. Fel’dman, V. I., Rare-Earth elements in astrobleme impactites. Geochemistry International, v. 32, pp. 24-48. 1995.

7. Fel’dman, V. I., Sazonova, L.V. and Granovsky,L.B., A classification of impactites based on petrographic and geological features (in Russian). Ispytateley Prirody Byull., Otdel. Geol., v. 57, pp. 84-94. 1982.

8. Grieve, R. A. F., Masaitis, V. L., The economic potential of terrestrial impact craters. International Geology Review, v. 36, pp. 105-151. 1994.

9. Grieve, R. A. F., Reny, G., Gurov, E.P. and Ryabenko,V.A., The melt rocks of the Boltysh impact crater, Ukraine, USSR. Contributions to Mineralogy and Petrology, v. 96, pp. 56-62. 1987.

10. Grieve, R. A. F., The record of impact on Earth: Implications for a major Cretaceous/Tertiary impact event. Geological Society of America, Special Paper 190, pp. 25-37. 1982.

11. Gurov, E. P., Kelley, S. P. , Koeberl, C. and Dykan, N. I., Sediments and Impact Rocks Filling the Boltysh Impact Crater, Meteoritics & Planetary Science, Vol. 42, No. 3, P. 335 – 358. 2007.

12. Gurov, E. P., Kelley, S. P., Koeberl., Ejecta of the Boltysh Impact Crater in the Ukranian Shield, Impact Markers in the Stratigraphic Record p. 179 – 202. 2003.

13. Gurov, E. P., Khmelnitsky, A. F., The Boltysh impact crater ejecta: Preservation stage and estimation of initial parameters (abstract). 4th International Workshop of the ESF Scientific Network on “Impact Cratering and Evolution of Planet Earth”. The Role of Impacts on the Evolution of the Atmosphere and Biosphere with Regard to Short- and Long-Term Changes, p. 80-81. 1995.

14. Gurov, E. P., Gurova, E.P. and Metalidi,S.V., The structure of a meteorite crater with central uplift (as exemplified by the Boltysh astrobleme) (abstract). Meteoritics, v. 26, pp. 253. 1991.

15. Gurov, E. P., Gurova, E. P., Some features of the structure of the crater with the central uplift (abstract). Eighth Soviet-American Microsymposium, pp. 35-36. 1988.

16. Gurov, E. P., Gurova, E. P., Impact structures on the Earth’s surface (in Russian). Geologicheskii Zhurnal, v. 47, pp. 117-124. 1987.

17. Gurov, E. P., Gurova, E.P. and Kolesov,G.M., Impactite composition of the Boltysh astrobleme (in Russian). Meteoritika, v. 45, pp. 150-155. 1986.

18. Gurov, E. P., Gurova, E. P., Boltysh astrobleme: Impact crater pattern with a central uplift. Lunar and Planetary Science XVI, pp. 310-311. 1985.

19. Gurov, E. P., Ryabenko, V. A., Impact structures of the Ukrainian shield. International Geological Congress 27, Moscow, Field Guide Excursion 098, pp. 143-159. 1984.

20. Gurov, E. P., Val’ter, A.A. and Rakitskaya,R.B., Coesite in rocks of meteorite explosion craters on the Ukrainian shield (in Russian). Mineralogicheskoye Obshchestvo Zapiski, v. 107, pp. 362-365. 1978.

21. Gurov, E. P., Val’ter, A. A., Ejecta from Boltysh meteorite crater in the Ukrainian shield (in Russian). Geologicheskii Zhurnal, v. 37, pp. 79-84. 1977.

22. Holker, Th., Deutsch, A.,., Strontium and Nd Isotopic compositions of impact melt rocks from the Boltysh and Lappajarvi Impact Structures. 59th Annual Meteoritical Society Meeting, Impact Craters and Ejecta I, Oral, METSOC 96 p. A62-63. 1996.

23. Holker, Th., Deutsch, A., The Boltysh Impact Structure, Ukraine: Geochemistry of the Melt Sheet, 27th Lunar and Planetary Science Conference. 1996.

24. Hölker, Th., Deutsch, A., The Boltysh impact structure, Ukraine: Geochemistry of the melt sheet (abstract). Lunar and Planetary Science, v. XXVII, pp. 555-556. 1996.

25. Holubev, V. A., Karpov, H M. and Popovichenko,V A., The meteorite-explosion origin of the Boltysh depression in the Kirovohrad district (in Ukrainian). Dopovidi Akademii Nauk Ukrains’koi SSSR, v. 1, pp. 10-12. 1974.

26. Ivanov, B. A., Basilevsky, A. T., Meteorite craters (in Russian). Priroda, v. 10, pp. 23-35. 1985.

27. Kashkarov, L. L., Nazarov, M.A., Kalinina, G.V., Lorenz, K.A., Konokova,N.N., Fission Track Dating of the Bolytsh Crater, Ukraine, LPSC XXIX, Lunar and Planetary Institute, Houston, TX, (CD-ROM). 1998.

28. Kelley, S. P., Gurov, E., Boltysh, another end-Cretaceous impact. Meteoritics and Planetary Science, v.37, p.1031-1043. 2002.

29. Khryanina, L. P., Meteorite craters on Earth (in Russian), Moscow, Nedra, pp. 73-82. 1987.

30. Khryanina, L. P., Meteorite craters on Earth (in Russian). Moscow, Nerda, 112 p. 1987.

31. Komarov, A. M., Raykhlin, A. I., Comparison of fission-track and potassium-argon dating of impactites. Doklady Akademii Nauk SSSR, v. 228, pp. 673-676. 1976.

32. Lorenz, C. A., Trace Elements Geochemistry in Impact Melts of the Bolytsh Crater, Ukraine, LPSC XXX, Lunar and Planetary Institute, Houston, TX, Abstr. 1597 (CD-ROM). 1999.

33. Masaitis, V. L., Mashchak, M. S., Bilateral symmetry of circular impact structures of astroblemes (in Russian). Meteoritika, v. 41, pp. 150-156. 1982.

34. Masaitis, V. L., Inclusions in impactites (in Russian). Meteoritika, v. 40, pp. 107-112. 1982.

35. Masaitis, V. L., Mashchak, M. S., Distribution of impactites in some large astroblemes on the U.S.S.R. territory (abstract). Lunar and Planetary Science XI, pp. 674-676. 1980.

36. Masaitis, V. L., Danilin, A.N., Maschak, M.S., Raykhlin, A.I., Selivanovskaya, T.V. and Shadenkov,Ye.M., The Geology of Astroblemes (in Russian). Leningrad, Nedra, 231 p. 1980.

37. Masaitis, V. L., Mashchak, M. S., Distribution of impactites in some large astroblemes of the U.S.S.R. territory (abstract). Lunar and Planetary Science, v. XI, pp. 674-676. 1980.

38. Masaitis, V. L., The morphology and sub-surface structure of terrestrial meteorite craters and astroblemes (in Russian). Pis’ma v Astronomichesky Zhurnal, v. 3, pp. 36-40. 1979.

39. Masaitis, V. L., Danilin, A.N. and Bogomolnaya,L.S., Crystallization of impact melt in Boltysh crater (abstract). Lunar and Planetary Science IX, pp. 699-701. 1978.

40. Masaitis, V. L., Mashchak, M.S., Raikhlin, A.I., Selivanovskaya, T.V., & Danilin,A., Meteorite craters and astroblemes in the USSR (in Russian). Doklady Akademii Nauk SSSR, v. 240, pp. 1191-1193. 1978.

41. Masaitis, V. L., Astroblemes in the USSR. International Geology Review, v. 18, pp. 1249-1258. 1975.

42. Orlova, A. O., Sazonova, L.V. and Fel’dman,V.I., Correlation between plagioclase crystal morphology and cooling kinetic of Boltysh astrobleme impact melt (USSR) (abstract). Meteoritics, v. 24, p. 312. 1989.

43. Phinney, W. C., Simonds, C. H., Dynamical implications of the petrology and distribution of impact melt rocks. Roddy, D.J., Pepin, R.O. and Merrill, R.B., eds., Impact and Explosion Cratering, Pergamon Press, New York, pp. 771-790. 1977.

44. Raikhlin, A. I., Danilin, A.N., Gorshkov, E.S. and Starunov,V.A., Contrasting differences in tagamites from the Popigai and Boltysh astroblemes (in Russian). Meteoritika, v. 42, pp. 144-148. 1983.

45. Reimold, W. U., Dressler, B. O., The economic significance of impact processes (abstract). Abstracts for the International Workshop on Meteorite Impact on the Early Earth, Perth, Australia, pp. 36-37. 1990.

46. Ryabenko, V. A., Val’ter, A. A., Meteorite explosion craters as an object of study in modern geology (in Russian). Visnyk, v. 1-6, pp. 7-16. 1977.

47. Schmidt, G., Palme, H., Os, Re, Ir, Ru, Rh, Pd, Au in borehole samples from the Clearwater East crater (Canada) and the Boltysh impact crater (Ukraine) (abstract). Lunar and Planetary Science XXVIII, pp. 1255-1256. 1997.

48. Schmidt, G., Clues to the Nature of the Impacting Bodies from Platinum-group Elements (Rhenium and Gold) in Borehole Samples from the Clearwater East Crater (Canada) and the Bolytsh Impact Crater (Ukraine), Meteoritics; vol. 32, p. 761-7. 1997.

49. Shcherban, O. N., A study of meteorite crater formation by comparing results of geological observations and numerical modelling on the computer (in Russian). Visnyk Akademiyi Nauk Ukrayinskoyi RSR, v. 3, pp. 11-19. 1983.

50. Stanyukovich, A. K., Probable meteorite craters (in Russian). Priroda, v. March, pp. 119-121. 1972.

51. Val’ter, A. A., Kolesov, G.M., Fel’dman, V.I. and Kapustkina,I.G., Contamination of the Boltysh astrobleme impactites with meteoritic matter (in Russian). Doklady Akademii Nauk SSSR, v. 295, pp. 164-167. 1987.

52. Val’ter, A. A., Dobryanski, Yu.P., Lazarenko, Y.Y. and Tarasyuk,V.K., Shock metamorphism of quartz and estimation of masses motion in the bases of Boltysh and Ilyinets astroblemes of the Ukrainian shield (abstract). Lunar and Planetary Science XIII, pp. 819-820. 1982.

53. Val’ter, A. A., Ryabenko, V. A., Explosion craters of the Ukrainian shield (in Russian). Kiev, Naukova dumka Press, 154 p. 1977.

54. Vishevsky, S. A., Pospelova, L. N., Some petrological and geochemical features of the problem of impact interactions (in Russian). Nekotoryye Petrologo-Geokhimicheskiye Osobennosti Problemy Impaktnykh Vzaumodeistviy, pp. 156-191. 1984.

55. Westbroek, H., Stewart, R., The formation, morphology, and economic potential of meteorite impact craters, CREWES Research Report v. 8, p. 1-26. 1996.

56. Yakovlev, O. I., Parfenova, O.V. and Ignatenko,K.I., Nonequilibrium condensation and high potassium impactites (in Russian). Meteoritika, v. 41, pp. 141-149. 1982.

57. Yakovlev, O. I., Vernadsky, V.I. and Parfenova,O.V., The role of vaporization and condensation in the formation of the chemical composition of impactites. Lunar and Planetary Science XI, pp. 1285-1287. 1980.

58. Yurk, Yu Yu., Yeremenko, G.K. and Polkanov,Yu.A., The Boltysh depression-a fossil meteorite crater (in Russian). Sovetskaya Geologiya, v. 2, pp. 138-144. 1975.

59. Yurk, Yu Yu., Yeremenko, G.K. and Polkanov,Yu.A., The Boltysh depression-a fossil meteorite crater. Sovetskaya Geologiya, v. 18, pp. 196-202. 1975.

60. Yurk, Yu Yu., Er’omenko, G.K. and Polkanov,Y.A., New data concerning the genesis of the Boltysh basin (in Russian). Akademiya Nauk Ukrainskoy RSR, Dopovidi, Seriya, B, Geologiya, Geolizika, Khimiyo, ta Biologiya, Kiev, pp. 244-248. 1974.

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