Abstract
The exposure of a carbonaceous siltstone sample to atmospheric entry, as part of the STONE 6 artificial meteorite experiment, has allowed a controlled investigation of the effect of heat shock during atmospheric entry on organic matter in carbonaceous meteorites and, potentially, sedimentary martian meteorites containing carbonaceous biomolecules. Thermal alteration is evident in an increase in structural order of the carbon (i.e. degree of graphitisation), preferential loss of thermally unstable compounds and substantial loss of extractable organic matter. There is a gradient of increasing alteration towards the outer, exposed margin of the rock, and also an increase in hydrocarbons that suggests outward migration following thermally-induced generation. The carbon has not been completely graphitised, and sufficient biomarker compounds survive to prove the biological origin of the organic matter. The experiment implies that meteorites of appropriate size could preserve evidence of biological activity on their parent body. © 2010 Elsevier Inc.
Original language | English |
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Pages (from-to) | 390-402 |
Number of pages | 13 |
Journal | Icarus |
Volume | 212 |
Issue number | 1 |
Early online date | 26 Nov 2010 |
DOIs | |
Publication status | Published - Mar 2011 |
Keywords
- meteorites
- thermal histories
- astrobiology
- Mars
- organic chemistry
- Tagish Lake Meteorite
- carbonaceous chondrites
- atmospheric entry
- structural-characterization
- Northern-Scotland
- Orcadian basin
- parent body
- Earth
- life