162-7 Geologic Map of Aram Chaos, Mars

Session: Planetary Geologic Mapping Across the Solar System

Presenting Author:

Authors:

Abstract:

We are producing a standardized USGS Scientific Investigation Map (SIM) series geologic map of Mars Transverse Mercator (MTM) quadrangles 05022, 05017, -00022, and -00017 that will link existing map coverage to the south and east, thereby enabling researchers to understand the role of water, either on the surface or subsurface, that formed the chaos terrain, channel and valley development, and origin of sulfate- and hematite-bearing units in an area on Mars where they are preserved at a local and regional scale. Importantly, the map will encompass initial and medial portions of the Ares Vallis channel from the chaotic terrain at Aram Chaos, Iani Chaos, and Hydaspis Chaos (-2.5 to 7.5°N latitude, 335 to 345°E longitude). The map will provide continuity along the path of the Uzboi-Ladon-Morava (ULM) system that extends from Argyre basin to the northern plains, providing a regional scale framework in which to interpret previous mapping to the south that extends from Uzboi to Morava Valles, and to further evaluate the role of this water in the formation of sulfate- and hematite-bearing deposits. 

All mapping is being done at 1:1,000,000 (1:1M) in ArcPro using a CTX mosaic as the basemap, supplemented with THEMIS Daytime and Nighttime IR mosaics, HRSC-MOLA DEM topography, HiRISE images, and CRISM spectral parameters. After two years of mapping, we have completed almost all of the line work for the map. Many linear features have been identified and mapped, such as fluvial valleys, crater rims, ridges, normal faults, grabens, and troughs. Geologic units identified and mapped thus far include craters and their ejecta, smooth crater floors, several different types of chaos terrain, light-toned sulfate-bearing deposits, and terrain dissected by channel outflows. As an example, we divided channel units in Ares Vallis into three types depending upon the extent of fluvial dissection and elevation. The Channel 1 unit is shallow with grooved terrain that formed from broad flows at the highest elevations. The Channel 2 unit is the steepest portion of the channel where the strongest flows carved down into the subsurface. The Channel 3 unit is the deepest and very flat with a high thermal inertia so it could be exposed older bedrock or debris from the final flow in the channel.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-6522

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