Red planet, ancient reservoirs: Martian basin architecture and in situ resource systems

Martian habitats will require reliable sources of energy, water, and minerals that can be developed on the planet itself. Thousands of basins on Mars are impact craters filled with sediment that are favorable settings for resource exploration because they contain heat, water, and pore space within thick stratigraphic successions. Lack of subduction on Mars has preserved these basins which may host water, geothermal energy derived from remnant heat and radioactive elements, hydrogen generated by reactions between water and ultramafic rocks, mineral-rich brines, methane sourced from deep crustal processes, and large volumes of pore space for subsurface storage under low Martian gravity. We present a method for reconstructing the thickness, lithology, and internal structure of sedimentary fill within basins using digital elevation data, geologic maps, a database of measurements from ~400,000 craters, and a new depositional model. Martian basin fill is divided into four depositional phases: (1) ejecta from crater-forming impact, (2) intra basin sourced alluvium from oversteepened and low stability crater rim and walls, (3) extra basin sourced fluvial, deltaic, and lacustrine sediment delivered by integrated drainage networks, and (4) post Noachian eolian deposition. Sediment volume in each basin is calculated by estimating pristine crater depth from crater diameter and using present day orbital elevation measurements. Drainage networks derived from Mars digital elevation models are combined with global geologic maps to determine sediment sources and transport pathways for each basin. Lithologic proportions for the fill of each crater are estimated using the lithology of the host rock beneath each crater and the lithology in the drainage feeding into the crater. These data are being used to build three-dimensional, finite element numerical models of prospective Martian basins that predict porosity, temperature, and pressure, providing a quantitative framework for evaluating resources and subsurface storage.