Date of Award
5-17-2005
Document Type
Thesis
Abstract
Analysis of a surface's crater population provides information to reconstruct the geologic history of a regional surface. Therefore, the population of sub-kilometer impact craters within Meridiani Planum, Mars has been assessed to constrain the nature and origin of unique hematite-rich deposits that occur in this region. Crater size-frequency distributions were compiled for 16,540 small craters in eleven images with varying hematite concentration. Results show that a complex crater obliteration process, probably aeolian activity, has operated continuously on the Meridiani region between 10 My and 3 Gy. More recently the surface process seems to have halted, possibly due to dune stabilization associated with a major climate shift. There is no evidence in the cratering record of an extensive, long-lived body of water that could have created the region's hematite deposits. While not required by the size-frequency distribution, some regional stripping and removal is permitted. In this case, the maximum erosional depth incurred in the last 3 Gy is limited to less than 50 meters. This is insufficient to have metamorphosed hematite as Lane et al. (2002) previously suggested. The size-frequency distributions suggest the hematite would have had to be emplaced very early in the history of Mars.
Recommended Citation
Pitiss, Sharon Ellen, "Constraints upon the history of Meridiani Planum, Mars using sub-kilometer crater counting" (2005). Geosciences . 125.
https://ualaska.researchcommons.org/uaf_grad_geosci/125
Handle
http://hdl.handle.net/11122/6945