JMDMT #2014 Microfossils of Cyanobacteria in Carbonaceous Meteorites

The James M. DuPont Meteorite Collection - with terrestrial CO2, then the isotopic composition of carbon and oxygen can provide important information about Martian H2O and CO2 and about weathering processes on Mars. We have used cosmogenic 14C as a label to identify the carbonate as a terrestrial or extraterrestrial alteration product. We will discuss the delta13C, delta18O and 14C compositions of CO2 released from acid-etching experiments of Allan Hills 84001, Nakhla and Zagami. Carbonates irradiated in space as small bodies will contain about 74 dpm/kg (3.2 x 108 atom 14C/g) [4]. This activity corresponds to a 14C/12C ratio (atom/atom) of 5.0 x 10-14 or 4.3% of the ratio found in modern (~1950AD) carbon [4]. Twentieth-century, terrestrial carbonates formed prior to atmospheric nuclear tests will have a 14C

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YouTube | November 24, 2008

Tags:. .meteorites. .dupont. .twentiethcentury. .martian. .terrestrial