TY - JOUR

T1 - Burial and Exhumation of Sedimentary Rocks Revealed by the Base Stimson Erosional Unconformity, Gale Crater, Mars

AU - Watkins, Jessica A.

AU - Grotzinger, John P.

AU - Stein, Nathan T.

AU - Banham, Steven G.

AU - Gupta, Sanjeev

AU - Rubin, David M.

AU - Morgan, Kathryn Stack

AU - Edgett, Kenneth S.

AU - Frydenvang, Jens

AU - Siebach, Kirsten L.

AU - Lamb, Michael P.

AU - Sumner, Dawn Y.

AU - Lewis, Kevin W.

PY - 2022

Y1 - 2022

N2 - Sedimentary rocks record the ancient climate of Mars through changes between subaqueous and eolian depositional environments, recognized by their stratal geometries and suites of sedimentary structures. Orbiter- and rover-image-based geologic mapping show a dynamic evolution of the 5-km-thick sedimentary sequence exposed along the flanks of Aeolis Mons (informally, Mt. Sharp) in Gale crater, Mars, by deposition of subaqueous strata followed by exhumation via eolian erosion and then deposition of overlying, onlapping strata of inferred eolian origin. This interpretation suggests that a significant unconformity should occur at the base of the onlapping strata, thus predicting lateral variations in elevation along the contact between the underlying Mt. Sharp group and overlying Stimson formation. Curiosity rover and high-resolution orbital image data quantify paleotopographic variability associated with the contact; similar to 140 m of net elevation change and a slope closely aligned with the modern topography is expressed along the regional contact. These results support the interpretation of an erosional unconformity between these strata and that it was likely formed as a result of eolian erosion within the crater, indicative of a transition from wet to dry climate and providing insight into the stratigraphic context, geologic history, and habitability within Gale crater.

AB - Sedimentary rocks record the ancient climate of Mars through changes between subaqueous and eolian depositional environments, recognized by their stratal geometries and suites of sedimentary structures. Orbiter- and rover-image-based geologic mapping show a dynamic evolution of the 5-km-thick sedimentary sequence exposed along the flanks of Aeolis Mons (informally, Mt. Sharp) in Gale crater, Mars, by deposition of subaqueous strata followed by exhumation via eolian erosion and then deposition of overlying, onlapping strata of inferred eolian origin. This interpretation suggests that a significant unconformity should occur at the base of the onlapping strata, thus predicting lateral variations in elevation along the contact between the underlying Mt. Sharp group and overlying Stimson formation. Curiosity rover and high-resolution orbital image data quantify paleotopographic variability associated with the contact; similar to 140 m of net elevation change and a slope closely aligned with the modern topography is expressed along the regional contact. These results support the interpretation of an erosional unconformity between these strata and that it was likely formed as a result of eolian erosion within the crater, indicative of a transition from wet to dry climate and providing insight into the stratigraphic context, geologic history, and habitability within Gale crater.

KW - Mars

KW - sedimentary

KW - unconformity

KW - erosion

KW - gale

KW - STRATIGRAPHY

KW - EVOLUTION

KW - MUDSTONE

KW - ANCIENT

KW - RECORD

U2 - 10.1029/2022JE007293

DO - 10.1029/2022JE007293

M3 - Journal article

VL - 127

JO - Journal of Geophysical Research: Solid Earth

JF - Journal of Geophysical Research: Solid Earth

SN - 0148-0227

IS - 7

M1 - e2022JE007293

ER -