1,2Subhasmita Swain, 3Enrico Mugnaioli, 3Anna Musolino, 4Markus Patzek, 5,6Beda Hofmann, 1,2,7Surya Snata Rout
Meteoritics & Planetary Science (in Press) Link to Article [DOI: 10.1111/maps.70245]
1School of Earth and Planetary Sciences, National Institute of Science Education and Research (NISER), Jatni, Khurda, India
2Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, India
3Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy
4Institut für Planetologie, University of Münster, Münster, Germany
5Institute of Geology, University of Bern, Bern, Switzerland
6Natural History Museum Bern, Bern, Switzerland
7Centre for Interdisciplinary Sciences (CIS), National Institute of Science Education and Research (NISER), Jatni, Khurda, India
Published by arrangement with John Wiley & Sons
Volatile-rich xenolithic clasts in different meteoritic breccias represent primitivesolar system material. Here, we report the mineralogy and organic maturity of C1, C2, andCM-like clasts present within five polymict ureilites, two polymict eucrites, one howardite,and one CR chondrite. Of all the clasts, the C1s are the most abundant, and the majorityhave mineralogy and organic maturity similar to the CI chondrites. Two C1 clasts show theleast altered polyaromatic organic matter, similar to Bells, Essebi, and a CR chondrite.A few C1 clasts have unique mineralogy with abundant Fe-rich olivine surroundingmagnetite grains. Such clasts show a Raman signature of mild to moderate heating effectsrelated to impact-shock processing. The Fe-rich olivine within these clasts formed aroundmagnetite grains from an aqueous fluid at a water/rock ratio of 0.1–0.2, T > 150 °C, andhigh activity of SiO 2 and Fe. Additionally, the Fe-rich olivine could have also formedthrough the reduction of magnetite by H 2 gas and SiO 2 (aq). The CM-like clasts are foundonly in the studied HED meteorites and have mineralogy and organic maturity similar to theCM chondrites. Only one CM-like clast shows unique Raman signatures, either due tothermal effects or the presence of unique organic precursor material. The C2 clasts showsimilarities with other C2 clasts in CH/CB chondrites. None of the studied clasts showsignatures of high degrees of thermal metamorphism like the subtype ≥3.1 chondrites.
