Spectroscopic analysis of bedrock exposures in the Martian highlands
Abstract
The THEMIS instrument aboard the 2001 Mars Odyssey spacecraft has provided a new view of the martian surface with 100 m/pixel daytime and nighttime multispectral infrared imaging. Numerous exposures of bedrock have been identified using THEMIS data. These exposures are found in a variety of southern highlands terrains, including crater floors and intercrater plains. We are characterizing the composition, thermophysical properties, and morphology of extensive, largely sediment-free bedrock surfaces in the intercrater plains of Mars. More than 30 spatially-contiguous, extensive, non-crater related bedrock surfaces with low albedo values (<0.16) have been identified to date. These bedrock exposures are investigated using THEMIS daytime and nighttime IR mosaics, MOC wide angle 256 ppd mosaic, MOLA elevation data binned at 128 ppd, and TES detector field-of-view overlays (full spatial resolution) of albedo and spectral emissivity. THEMIS and TES data are used for derivation of surface emissivity and estimation of mineral abundance allowing classification into units based on composition, morphology, texture and other noted characteristics. Building on previous global studies, we use infrared and VIS/NIR spectral data to determine surface mineralogy and examine how representative the martian surface layer is of near-surface underlying bedrock units. This study, for the first time, systematically probes a window into the stratigraphy and composition of globally distributed ancient terrains on Mars.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2005
- Bibcode:
- 2005AGUFM.P21C0168R
- Keywords:
-
- 5410 Composition (1060;
- 3672);
- 5415 Erosion and weathering;
- 5464 Remote sensing;
- 5470 Surface materials and properties;
- 6225 Mars