Proceedings of the Japan Academy, Series B
Online ISSN : 1349-2896
Print ISSN : 0386-2208
ISSN-L : 0386-2208
Original Article
Hypervelocity collision and water-rock interaction in space preserved in the Chelyabinsk ordinary chondrite
Eizo NAKAMURATak KUNIHIROTsutomu OTAChie SAKAGUCHIRyoji TANAKAHiroshi KITAGAWAKatsura KOBAYASHIMasahiro YAMANAKAYuri SHIMAKIGray E. BEBOUTHitoshi MIURATetsuo YAMAMOTOVladimir MALKOVETSVictor GROKHOVSKYOlga KOROLEVAKonstantin LITASOV
Author information
JOURNALS FREE ACCESS FULL-TEXT HTML
Supplementary material

2019 Volume 95 Issue 4 Pages 165-177

Details
Abstract

A comprehensive geochemical study of the Chelyabinsk meteorite reveals further details regarding its history of impact-related fragmentation and melting, and later aqueous alteration, during its transit toward Earth. We support an ∼30 Ma age obtained by Ar-Ar method (Beard et al., 2014) for the impact-related melting, based on Rb-Sr isotope analyses of a melt domain. An irregularly shaped olivine with a distinct O isotope composition in a melt domain appears to be a fragment of a silicate-rich impactor. Hydrogen and Li concentrations and isotopic compositions, textures of Fe oxyhydroxides, and the presence of organic materials located in fractures, are together consistent with aqueous alteration, and this alteration could have pre-dated interaction with the Earth’s atmosphere. As one model, we suggest that hypervelocity capture of the impact-related debris by a comet nucleus could have led to shock-wave-induced supercritical aqueous fluids dissolving the silicate, metallic, and organic matter, with later ice sublimation yielding a rocky rubble pile sampled by the meteorite.

Information related to the author
© 2019 The Japan Academy
Previous article
feedback
Top