GEOMORPHOLOGICAL EXPRESSIONS OF LAYERED ROCKS IN THE WESTERN USA. REASONABLE EARTH-MARS ANALOGS?

Layered surface rocks on Earth and Mars show comparable morphological characteristics in response to weathering and erosion, and these characteristics can be used to differentiate between rock types. Although there is some uncertainty with regard to the exact nature of rocks that show Earth-analog features on Mars; a large number of geomorphic traits are visible in high resolution imagery of Mars and can be compared with their Earth counterparts.

Numerous sites in the western U.S. show geomorphic features, such as pediments, mesa, canyons, mass movements, dunes, slope drainage patterns, and numerous others that are also observed in orbital images from Mars. By combining ground-truth from basaltic flows in Idaho, flood deposits and glacial lake deposits in Montana, as well as a combination of sedimentary and volcanic deposits in Utah and Arizona, with satellite imagery, we are refining interpretations of geologic histories for comparable features on the surface of Mars. By also focusing on erosional inconsistencies between otherwise similar features from Earth and Mars, we can identify Martian geomorphic features that in spite of outward similarity, record a history that does not parallel its Earth analog.

Through systematic exploration and comparison of erosional landscapes from Earth and Mars we intend to arrive at proxies for the determination of unit composition via erosional characteristics. This approach should facilitate a better understanding of geomorphic features visible on orbital images from Mars. Results from this summer's field study will be presented at conference.