ABIOGENIC LAYERED CARBONATES ASSOCIATED WITH SERPENTINIZATION: WHY MARTIAN 'STROMATOLITES' MIGHT NOT BE FOSSILS

摘要

Deciphering the complex interactions between biological and geological parameters has required increasingly interdisciplinary study and collaboration as our appreciation for the significance of biota in the interpretation of these and other geological processes has grown. We have brought together a geochemist, a geologist and geomicrobiologists to examine whether life has played a key role in creating this potential modern analogue to Archean environments on Earth and their relationship to the prospect of finding life on Mars. The absence of any biological signal in the ultrastructure of these modern structures suggests that they represent a non-biological end-member in the ongoing debate regarding the origin of ancient stromatolites. If layered carbonates are found on Mars, they may well have been formed by a similar abiogenic process, rather than a biological one. Therefore, stromatolites or layered carbonated sediments cannot be used as unequivocal evidence for life, if found on Mars.