Structural-Mineralogical Characteristic of a Dark Lithology Fragment of the Chelyabinsk (LL5) Chondrite

UDC 523.681

А.L. Girich, V.P. Semenenko, N.V. Kychan

M.P. Semenenko Institute of Geochemistry, Mineralogy and Ore Formation of the NAS of Ukraine

34, Acad. Palladina Pr., Kyiv-142, Ukraine, 03680


Structural-Mineralogical Characteristic of a Dark Lithology Fragment of the Chelyabinsk (LL5) Chondrite

Language: Ukrainian

Mineralogical journal 2015, 37 (4): 46-57

Abstract: The results of structural-mineralogical and chemical study of one of fragmentary samples of the Chelyabinsk (LL5) chondrite are given. Tetiana Shtan, correspondent of Ukrainian television studio ICTV, presented this sample to the Committee for Meteorites of the NAS of Ukraine for research. The sample is 1.1 g in weight, 1.1 × 0.8 cm in size and has a round shape and a fusion crust on two sides. According to the structure, mineral and chemical compositions the sample was diagnosed as a dark lithology of chondrite and is similar to other dark samples of the Chelyabinsk meteorite studied by previous researchers. The sample has a typical irregular-grained chondritic texture with chondrule relicts and rare Fe, Ni-iron and troilite assemblages and composes two black shock veins. The majority of silicates are penetrated by iron sulfide microveins. Main minerals are olivine (Fa28.4—29.8) and Ca-poor pyroxene (Fs23.7—25.8En74.1—74.7Wo1.11—1.57). Secon dary ones are Fe, Ni-iron (kamacite and taenite), troilite, Ca-rich pyroxene (Fs8.76—9.64En45.6—46.3Wo44.8—45.2), normative plagioclase (Ab83.4—86.9An9.28—12.4Or3.30—6.37), chromite, merrillite and chloroapatite. The black shock veins are composed by a fine-recrystallized silicate glass with coarse olivine and pyroxene grains and are enriched with small troilite and Fe, Ni-iron grains. The presence of a widespread shock metamorphism structures and the character of their display indicate the multistage shock-metamorphic history of the Chelyabinsk chondrite parent body. The most intensive impact in the cosmic history of the meteorite, accompanied by the melting of some part of the material at temperature ≥1450 °С, is probably connected with formation of a monomict breccia on the surface of its parent body. The stage of a shockmetamorphic transformation of the studied sample material was identified as S5, that corresponds to the shock pressure 45—55 GPa and shock temperature 600—850 °С.

Keywords: meteorite, breccia, chondrite, dark lithology, shock black veins, shock metamorphism, fusion crust.


1. Anphilogov, V.N., Belogub, E.V., Blinov, I.A., Eremyashev, V.E., Kabanova, L.Y., Lebedeva, S.M., Lonschakova, G.F. and Khvorov, P.V. (2013), Lithosphere, Yekaterinburg, No 3, pp. 118-129.
2. Berzin, S.V., Erokhin, Y.V., Ivanov, K.S. and Hiller, V.V. (2013), Lithosphere, Yekaterinburg, No 3, pp. 106-117.
3. Galimov, E.M., Kolotov, V.P., Nazarov, M.A., Kostitsin, Y.A., Kubrakova, I.V., Kononkova, N.N., Roshchina, I.A., Alekseev, V.A., Kashkarov, L.L., Badykov, D.D. and Sevastianov, V.S. (2013), Geokhimiya, Moskva, Vol. 51 No 7, pp. 580-598. 
4. Semenenko, V.P. and Perron, K. (1996), Mineral. Journ. (Ukraine), Kyiv, Vol. 18 No 4, pp. 26-37.
5. Sobotovich, E.V. and Semenenko, V.P. (1984), Veshchestvo meteoritov, Naukova dumka, Kiev, 192 p.
6. Chirvinskiy, P.N. (1967), Pallasity, ih mineralogo-himicheskiy sostav, polozhenie v ryadu drugih meteoritov i voprosy proishozhdeniya, Nedra, Moskva, 288 p.
7. Sharyhin, V.V., Karmanov, N.S., Podhornykh, N.M. and Tomilenko, A.A. (2014), Materialy Vseros. nauch. konf. "Mereorit Chelyabinsk - god na Zemle", Chelyabinsk, pp. 637-653.
8. Sharyhin, V.V., Timina, N.Yu., Karmanov, N.S., Tomilenko, A.A. and Podhornykh, N.M. (2014), Materialy Vseros. nauch. konf. "Mereorit Chelyabinsk - god na Zemle", Chelyabinsk, pp. 654-666.
9. Barnes, S.J., Fiorentini, M.L., Austin, P., Gessner, K., Hough, R.M. and Squelch, A.P. (2008), Geology, Vol. 36, pp. 655-658. 
10. Bischoff, A., Scott, E.R.D., Metzler, K. and Goodrich, C.A. (2006), Meteorites and the Early Solar System II, in Lauretta, D.S. and McSween Jr., H.Y. (eds), Univ. of Arizona Press, Tucson, pp. 679-712.
11. Bunch, T.E. and Rajan, R.S. (1988), Meteorites and the Early Solar System, in Kerridge, J.F. and Matthews, M.S. (eds), Univ. of Arizona Press, Tucson, pp. 144-164.
12. Gaetani, G.A. and Grove, T.L. (1999), Earth and Planet. Sci. Lett., Vol. 169, pp. 147-163. 
13. Krot, A.N., Keil, K., Goodrich, C.A. and Scott, E.R.D. (2004), Treatise on geochemistry, Vol. 1, Meteorites, comets and planets, in Davis, A.M. (ed.), Elsevier-Pergamon, Oxford, pp. 83-128.
14. Minarik, W.G., Ryerson, F.J. and Watson, B.E. (1996), Science, Vol. 272, pp. 530-533. 
15. Semenenko, V.P. and Golovko, N.V. (1994), Geochim. et cosmochim. acta, Vol. 58, pp. 1525-1535. 
16. Semenenko, V.P. and Perron, C. (2005), Meteoritics and Planet. Sci., Vol. 40, pp. 173-185. 
17. Stöffler, D., Keil, K. and Scott, E.R.D. (1991), Geochim. et cosmochim. acta, Vol. 55, pp. 3845-3867. 
18. Tomkins, A.G., Weinberg, R.F., Schaefer, B.F. and Langendam, A. (2013), Geochim. et cosmochim. acta, Vol. 100, pp. 41-59.