Paper No. 12
Presentation Time: 4:05 PM


DOHM, James M., Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Meguro, Tokyo, 152-8551, Japan, MARUYAMA, Shigenori, Earth-Life Science Institute, Tokyo Institute of Techology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8551, Japan, EL-MAARRY, Ramy, Physikalisches Institut, Bern Universität, Bern, 3012, Switzerland, SOARE, Richard J., Geography, Dawson College, 3040 Sherbrooke Street West, Montreal, QC H3Z 1A4, Canada, WILLIAMS, J.-Pierre, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, CONWAY, Susan J., Department of Physical Sciences, Walton Hall, Open University, Milton Keynes, MK7 6AA, United Kingdom and MIYAMOTO, Hirdy, The Museum, The University of Tokyo, Tokyo, 113-003, Japan,

The Argyre impact created a giant catchment for water and rock materials since roughly 3.93 Ga based on detailed stratigraphy and crater statistics unfolded through a NASA PG&G mapping project. A giant lake formed in the aftermath of the event (likely related to impact-generated meltwater from an ice sheet and associated rainfall and migration of subsurface and surface water into the basin), feeding the far-reaching Uzboi Vallis system, with a volume nearing that of the Mediterranean Sea; other lakes filled the impact-derived local basins as well. The lakes would soon freeze and the once lacustrine environment would transition into glacial and periglacial environments. Through time, liquid water/water-ice would wane, though not totally being depleted, as there would be subsequent Tharsis-driven, transient hydrological cycling (including enhanced geological and climatic activities). Water enrichment in the Argyre basin (including valleys and local basins among the rim materials) continues until present-day. Examples of geologically-recent and/or present-day activity includes the formation of small-sized polygonal-patterned ground, gullies and possible open-system pingos, flow-like features of the valley-fill materials, which includes glacier-like features, and activity along graben-like features.

Mars is the prime target to search for life beyond Earth, as it once had Habitable-Trinity conditions (i.e., interaction among landmass, ocean, and atmosphere; see Dohm and Maruyama, this conference) prior to the Argyre impact event. The long-term water enrichment, heat generation from the Argyre impact, basement structures which piped water into the basin from far-reaching geologic provinces, potential nutrient-enriched primordial crustal materials, extant ice, potential near-surface groundwater in places, and potential venting of magma and volatiles collectively point to the Argyre basin region as a prime candidate for future exploration of possible life.