  Most of Mars' ancient sedimentary rocks by volume are in wind-eroded
sedimentary mounds, but the connections between mound form and wind erosion are
unclear. We perform mesoscale simulations of different crater and mound
morphologies to understand the formation of sedimentary mounds. As crater depth
increases, slope winds produce increased erosion near the base of the crater
wall, forming mounds. Peak erosion rates occur when the crater depth is ~2 km.
Mound evolution depends on the size of the host crater. In smaller craters
mounds preferentially erode at the top, becoming more squat, while in larger
craters mounds become steeper-sided. This agrees with observations where
smaller craters tend to have proportionally shorter mounds, and larger craters
have mounds encircled by moats. If a large-scale sedimentary layer blankets a
crater, then as the layer recedes across the crater it will erode more towards
the edges of the crater, resulting in a crescent-shaped moat. When a 160 km
diameter mound-hosting crater is subject to a prevailing wind, the surface wind
stress is stronger on the leeward side than on the windward side. This results
in the center of the mound appearing to `march upwind' over time, and forming a
`bat-wing' shape, as is observed for Mt. Sharp in Gale crater.
