A Field Guide to Finding Fossils on Mars
Name
McMahon_et_al-2018-Journal_of_Geophysical_Research%3A_Planets.pdf
Size
2.32 MB
Format
Adobe PDF
Checksum (MD5)
4563fe56ed595355d2e027b035692a18
Author(s)
McMahon, S.
Grotzinger, J. P.
Milliken, R. E.
Fraeman, A.
Williford, K. H.
Briggs, D. E. G.
Bosak, Tanja
Summons, Roger E
El Daye, Mirna
Newman, Sharon
Date Issued
May 2018
Journal
Journal of Geophysical Research: Planets
Publisher
American Geophysical Union (AGU)
Citation
McMahon, S., et al. “A Field Guide to Finding Fossils on Mars.” Journal of Geophysical Research: Planets 123, 5 (May 2018): 1012–1040 ©2018 The Authors
Version
Final published version
Abstract
The Martian surface is cold, dry, exposed to biologically harmful radiation and apparently barren today. Nevertheless, there is clear geological evidence for warmer, wetter intervals in the past that could have supported life at or near the surface. This evidence has motivated National Aeronautics and Space Administration and European Space Agency to prioritize the search for any remains or traces of organisms from early Mars in forthcoming missions. Informed by (1) stratigraphic, mineralogical and geochemical data collected by previous and current missions, (2) Earth's fossil record, and (3) experimental studies of organic decay and preservation, we here consider whether, how, and where fossils and isotopic biosignatures could have been preserved in the depositional environments and mineralizing media thought to have been present in habitable settings on early Mars. We conclude that Noachian-Hesperian Fe-bearing clay-rich fluvio-lacustrine siliciclastic deposits, especially where enriched in silica, currently represent the most promising and best understood astropaleontological targets. Siliceous sinters would also be an excellent target, but their presence on Mars awaits confirmation. More work is needed to improve our understanding of fossil preservation in the context of other environments specific to Mars, particularly within evaporative salts and pore/fracture-filling subsurface minerals.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1029/2017JE005478
