Soil-like deposits observed by Sojourner, the Pathfinder rover

Henry J. Moore; Donald B. Bickler; Joy A. Crisp; Howard J. Eisen; Jeffrey A. Gensler; Albert F.C. Haldemann; Jacob R. Matijevic; Lisa K. Reid; Ferenc Pavlics

doi:10.1029/1998je900005

USGS · 70021698

Soil-like deposits observed by Sojourner, the Pathfinder rover

Henry J. Moore·Donald B. Bickler·Joy A. Crisp·Howard J. Eisen·Jeffrey A. Gensler·Albert F.C. Haldemann·Jacob R. Matijevic·Lisa K. Reid·Ferenc Pavlics

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Abstract

Most of the soil-like materials at the Pathfinder landing site behave like moderately dense soils on Earth with friction angles near 34°-39° and are called cloddy deposits. Cloddy deposits appear to be poorly sorted with dust-sized to granule-sized mineral or rock grains; they may contain pebbles, small rock fragments, and clods. Thin deposits of porous, compressible drifts with friction angles near 26°-28° are also present. Drifts are fine grained. Cohesions of both types of deposits are small. There may be indurated soil-like deposits and/or coated or crusted rocks. Cloddy deposits may be fluvial sediments of the Ares-Tiu floods, but other origins, such as ejecta from nearby impact craters, should be considered. Drifts are probably dusts that settled from the Martian atmosphere. Remote-sensing signatures of the deposits inferred from rover observations are consistent with those observed from orbit and Earth.

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Journal of Geophysical Research E: Planets Article

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Henry J. Moore, Donald B. Bickler, Joy A. Crisp, Howard J. Eisen, Jeffrey A. Gensler, Albert F.C. Haldemann, Jacob R. Matijevic, Lisa K. Reid, Ferenc Pavlics. 1999. Soil-like deposits observed by Sojourner, the Pathfinder rover. https://doi.org/10.1029/1998je900005

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