GEOLOGIC MAP OF THE MSL CURIOSITY ROVER EXTENDED MISSION TRAVERSE OF AEOLIS MONS, GALE CRATER, MARS

An orbital image-derived geologic map of the Mars Science Laboratory (MSL) Curiosity rover landing ellipse created by the MSL science team prior to landing [1] played an important role in planning hypothesis-driven surface science operations during the first 3 years of the MSL mission. However, upon arriving at the base of Aeolis Mons, the rover reached the edge of the landing ellipse and the corresponding MSL team geologic map. This study presents a mapping effort of orbital images from the High Resolution Imaging Science Experiment (HiRISE) camera that extends the coverage of the landing ellipse geologic map to include the lower strata of Aeolis Mons to be traversed by the Curiosity rover during its extended mission. Mapping was done at a scale of 1:500, resulting in the most detailed map to-date of this interval of Aeolis Mons and a significant improvement upon previous orbital geologic maps of Gale crater. The map area covers a 3 by 5 km swath of lower Aeolis Mons and includes the southernmost edge of Aeolis Palus, exposures of the Murray and Stimson formations, the hematite-bearing ridge, clay trough, and the transition between the clay trough and overlying sulfate-bearing strata. Orbital geologic units were defined in gray-scale and color HiRISE images primarily by differences in tone, brightness, and surface texture. Where possible, geomorphic units, such as the hematite-bearing ridge or the ridged fan, were distinguished from stratigraphic units, such as the Murray or Stimson formations. The mapping effort presented here provides the geologic context and stratigraphic framework for science operations planned by the Curiosity rover team during its extended mission phase and is used to identify the location of meter-scale well-exposed outcrops, geologic contacts, and other geologic features of interest as targets for exploration by the rover. Cross-sections through the hematite-bearing ridge, clay trough, and sulfate-bearing strata enable a comparison of the stratigraphic relationship of meter-scale geologic and geomorphic unit exposures mapped as part of this effort with previous mineralogical unit mapping based on CRISM and THEMIS spectral data.

[1] Grotzinger et al. (2014), Science, 343, 6169, doi: 10.1126/science.1242777.