Intracrater Terminal Dune Fields in Arabia Terra, Mars

Craters are the most prevalent basins and potential depo-centers of sediment on Mars. Within these craters and extending from them, terminal dune fields and wind streaks are abundant, indicating active sediment transport and providing a way to study how wind and sediment interact with crater topography. Here, we explore the role of craters as both sources and sinks in the modern martian sedimentary cycle. Our results show that craters with low albedo wind streaks (indicative of sediment transport out of a crater and downwind dust removal) have lower crater wall slopes (9.4° ±5.5°) compared to craters without wind streaks (17° ±5.8°). We interpret that crater wall slopes play a dominant role in whether sediment is transported out of a crater basin, and infer, from measurements of craters on Mars, that a crater transitions from being a net sediment sink to a net sediment source when crater wall slopes decrease to ~15°. This threshold value is consistent with limits of bedform climb observ...