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Ice Lens Formation and Frost Heave at the Phoenix Landing SiteSeveral lines of evidence indicate that the volume of shallow ground ice in the martian high latitudes exceeds the pore volume of the host regolith. Boynton et al. found an optimal fit to the Mars Odyssey Gamma Ray Spectrometer (GRS) data at the Phoenix landing site by modeling a buried layer of 50-75% ice by mass (up to 90% ice by volume). Thermal and optical observations of recent impact craters in the northern hemisphere have revealed nearly pure ice. Ice deposits containing only 1-2% soil by volume were excavated by Phoenix. The leading hypothesis for the origin of this excess ice is that it developed in situ by a mechanism analogous to the formation of terrestrial ice lenses and needle ice. Problematically, terrestrial soil-ice segregation is driven by freeze/thaw cycling and the movement of bulk water, neither of which are expected to have occurred in the geologically recent past on Mars. If however ice lens formation is possible at temperatures less than 273 K, there are possible implications for the habitability of Mars permafrost, since the same thin films of unfrozen water that lead to ice segregation are used by terrestrial psychrophiles to metabolize and grow down to temperatures of at least 258 K.
Document ID
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Zent, A. P.
(NASA Ames Research Center Moffett Field, CA, United States)
Sizemore, H. G.
(Oak Ridge Associated Universities, Inc. TN, United States)
Remple, A. W.
(Oregon Univ. Eugene, OR, United States)
Date Acquired
August 25, 2013
Publication Date
June 13, 2011
Subject Category
Report/Patent Number
Meeting Information
Meeting: 2011 International Conference: Exploring Mars Habitability
Location: Lisbon
Country: Portugal
Start Date: June 13, 2011
End Date: June 15, 2011
Sponsors: European Space Agency
Funding Number(s)
WBS: WBS 203959.
Distribution Limits
Public Use Permitted.
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