Noble gases, nitrogen and cosmic ray exposure age of the Sulagiri chondrite

The Sulagiri meteorite fell in India on 12 September 2008, LL6 chondrite class is the largest among all the Indian meteorites. Isotopic compositions of noble gases (He, Ne, Ar, Kr and Xe) and nitrogen in the Sulagiri meteorite and cosmic ray exposure history are discussed. Low cosmogenic (Ne-22/Ne-21) c ratio is consistent with irradiation in a large body. Cosmogenic noble gases indicate that Sulagiri has a 4 pi cosmic- ray exposure (CRE) age of 27.9 +/- 3.4 Ma and is a member of the peak of CRE age distribution of LL chondrites. Radiogenic He-4 and Ar-40 concentrations in Sulagiri yields the radiogenic ages as 2.29 and 4.56 Ga, indicating the loss of He from the meteorite. Xenon and krypton are mixture of Q and spallogenic components. (C) 2016, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B. V.