Wind-blown sandstones cemented by sulfate and clay minerals in Gale Crater, Mars

Gale Crater contains Mount Sharp, a similar to 5km thick stratigraphic record of Mars' early environmental history. The strata comprising Mount Sharp are believed to be sedimentary in origin, but the specific depositional environments recorded by the rocks remain speculative. We present orbital evidence for the occurrence of eolian sandstones within Gale Crater and the lower reaches of Mount Sharp, including preservation of wind-blown sand dune topography in sedimentary strataa phenomenon that is rare on Earth and typically associated with stabilization, rapid sedimentation, transgression, and submergence of the land surface. The preserved bedforms in Gale are associated with clay minerals and elsewhere accompanied by typical dune cross stratification marked by bounding surfaces whose lateral equivalents contain sulfate salts. These observations extend the range of possible habitable environments that may be recorded within Gale Crater and provide hypotheses that can be tested in situ by the Curiosity rover payload. Key Points Lower Mt. Sharp in Gale Crater exhibits evidence for wind-blown sandstones Preserved dune topography is indicative of specific environmental conditions Some preserved dunes contain clays, possibly as authigenic cements