Puncturing Mars: How impact craters interact with the Martian cryosphere

摘要: Abstract Geologic evidence suggests that the Martian surface and atmospheric conditions underwent major changes in late Noachian, with a decline observable water-related features, suggestive of transition to dryer colder climate. Based on assumption, we have modeled consequences impacts into ∼2–6 km-thick cryosphere. We calculate medium-sized (few 10 s km diameter) impact craters can physically and/or thermally penetrate through this cryosphere, creating liquid water melting subsurface ice an otherwise dry frozen environment. The interaction target rock produces alteration phases thermochemical modeling predicts will include hydrous silicates (e.g., nontronite, chlorite, serpentine). Thus, even small are environments combine presence minerals make them potential sites for life proliferate. Expanding well-known effects large sites, conclude as ∼5–20 km (depending latitude) excavate volumes material from while delivering sufficient heat create (through ground ice) drive hydrothermal activity. This connection between made by formation these small, thus more frequent, may also represent most favorable test hypothesis early Mars.