In Situ Study of the Sulphur Isotopic Compositions of Fe-ni Sulphides in Ci1, Cm1, and Tagish Lake Carbonaceous Chondrites: Preliminary Results

Fe-ni Sulphides in Tagish Lake and Ci1 and Cm2 Carbonaceous

Different degrees of aqueous alteration in sulphides within the CI1 chondrites

Introduction: It has been well documented that all of the CI1 chondrites have undergone extensive aqueous alteration, [1] which has modified the texture and composition of the minerals present. In this study, we look at the effect of aqueous alteration on Fe-Ni sulphides in four different CI1 chondrites, with a view to identifying variable degrees of aqueous alteration within CI1 chondrites. Me...

Continued Investigation of the Light Element Geochemistry of Tagish Lake

Introduction: Preliminary analysis of the light element stable isotope geochemistry of the Tagish Lake primitive carbonaceous chondrite showed that it was a carbonate-rich meteorite containing abundant presolar grains [1, 2]. Tagish Lake seemed to be more carbon-rich than CI chondrites, with over 5 wt. % carbon distributed almost equally between organic and inorganic (mostly carbonate) componen...

Tagish Lake: Bulk Chemistry and Terrestrial Alteration

Introduction: The Tagish Lake carbonaceous chondrite has been the focus of much attention since its isotopic, trace element, and mineralogic properties demonstrate a unique history [1-5]. We have analyzed both pristine and disturbed Tagish Lake samples for 12 major and minor elements by ICPMS and ICPOES. When combined with data collected earlier [1], this brings the total number of elements qua...

Organic Constituents in Carbonaceous Chondrites; Evidence for Preservation of Pristine Particles of Mixed Origins

Introduction: Carbonaceous chondrites are primitive meteorites that have sampled the oldest conden-sates of the solar system. They have accreted components of various origins: CAIs (also known as refrac-tory inclusions), chondrules, ice, noble gases and or-ganics. Radioactive decay of short lived radionucleides quickly heated these parent bodies and drove thermal metamorphism and aqueous altera...