Separation of Q-Noble gas carrier from bulk carbon in enstatite chondrites by stepped combustion

Detailed stepped combustion of HF-HCl residues from carbonaceous and enstatite chondrites suggest Q-noble gas carrier is different from bulk carbon in the meteorites

Cryptoendolith communities in Antarctic dry valley region sandstones: Potential analogues of Martian life-forms

We are studying cryptoendolith-bearing Antarctic sandstones, to determine if the microbes alter the elemental composition of the rocks. If there is an effect, then it might be a tracer for the presence of micro-organisms in martian surface materials

Xenon isotopes in nanodiamonds and other presolar grains

pdf freely available cb 18/07/0

Noble gases in Tagish Lake

From the introduction: Tagish Lake has been classified as a CI2 chondrite [1] with an interstellar grain abundance enhanced over that of CI1 and CM2 chondrites [2]. Noble gases have been used as markers for the presence of exotic, presolar grains in chondritic meteorites: Xe-HL (nanodiamonds) and Xe-s/Ne-E (SiC). We have measured 4He, Ne, Ar and Xe in whole-rock Tagish Lake, and an orthophosphoric acid-resistant residue, in an effort to define more precisely the relative abundances of the different presolar components present, and to verify whether or not the meteorite has an enhanced complement of presolar diamonds. For comparison, whole-rock samples of Orgueil and Murchison have also been analysed using the same experimental procedure

Carbon and nitrogen isotope ratios in meteoritic organic matter: indicators of alteration processes on the parent asteroid

Macromolecular organic materials in chondrites display significant variations in carbon and nitrogen stable isotopes. In recent years, these variations have been interpreted as a record of aqueous and thermal processing on asteroids shortly after the birth of the Solar System. In this paper we review and summarize the key data and main interpretative approaches related to this study area. Armed with these methods we attempt to reinterpret the whole rock chondrite data set in the literature

An integrated mineralogical, petrographic, light stable isotope and noble gas investigation of Sahara 99201 ureilite

New ureilite Sahara 99201 has been investigated to determine mineralogy, petrography, light stable isotopes and noble gases. The sample is a typical olivine pigeonite ureilite (Fo 78, Wo 10, En 72). C, N, O and Ar are consistent with other ureilites