2012/05/30 by Edwin S. Kite, K. W. Lewis, Kite, Edwin S. +3
Earth and Planetary Sciences · Physics and Astronomy · #Aeolian processes and effects #Astro and Planetary Science #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Geology and Paleoclimatology Research #Geophysics (physics.geo-ph) #Planetary Science and Exploration
paper · pdf · doi:10.48550/arxiv.1205.6840
openalex publication_date 2012/05/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Ancient sediments provide archives of climate and habitability on Mars. Gale\nCrater, the landing site for the Mars Science Laboratory (MSL), hosts a 5 km\nhigh sedimentary mound. Hypotheses for mound formation include evaporitic,\nlacustrine, fluviodeltaic, and aeolian processes, but the origin and original\nextent of Gale's mound is unknown. Here we show new measurements of sedimentary\nstrata within the mound that indicate ~3 degree outward dips oriented radially\naway from the mound center, inconsistent with the first three hypotheses.\nMoreover, although mounds are widely considered to be erosional remnants of a\nonce crater-filling unit, we find that the Gale mound's current form is close\nto its maximal extent. Instead we propose that the mound's structure,\nstratigraphy, and current shape can be explained by growth in place near the\ncenter of the crater mediated by wind-topography feedbacks. Our model shows how\nsediment can initially accrete near the crater center far from crater-wall\nkatabatic winds, until the increasing relief of the resulting mound generates\nmound-flank slope-winds strong enough to erode the mound. Our results indicate\nmound formation by airfall-dominated deposition with a limited role for\nlacustrine and fluvial activity, and potentially limited organic carbon\npreservation. Morphodynamic feedbacks between wind and topography are widely\napplicable to a range of sedimentary mounds and ice mounds across the Martian\nsurface, and possibly other planets.\n