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Exopaleontology and the search for a fossil record on MarsAlthough present Martian surface conditions appear unfavorable for life as we know it, there is compelling geological evidence that the climate of early Mars was much more Earth-like, with a denser atmosphere and abundant surface water. The fact that life developed on the Earth within the first billion years of its history makes it quite plausible that life may have also developed on Mars. If life did develop on Mars, it is likely to have left behind a fossil record. This has led to the development of a new subdiscipline of paleontology, herein termed 'exopaleontology', which deals with the exploration for fossils on other planets. The most important factor enhancing microbial fossilization is the rapid entombment of microorganisms by fine-grained, stable mineral phases, such as silica, phosphate, or carbonate. The oldest body fossils on Earth are preserved in this way, occurring as permineralized cells in fine-grained siliceous sediments (cherts) associated with ancient volcanic terranes in Australia and South Africa. Modern terrestrial environments where minerals may precipitate in the presence of microorganisms include subaerial thermal springs and shallow hydrothermal systems, sub-lacustrine springs and evaporitic alkaline lakes, zones of mineralization within soils where 'hardpans' (e.g. calcretes, silcretes) form, and high latitude frozen soils or ground ice.
Document ID
19940030919
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Farmer, Jack D.
(NASA Ames Research Center Moffett Field, CA, United States)
Desmarais, D. J.
(NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1994
Publication Information
Publication: Lunar and Planetary Inst., The Twenty-Fifth Lunar and Planetary Science Conference. Part 1: A-G
Subject Category
Lunar And Planetary Exploration
Accession Number
94N35425
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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