Erosion around a large-scale topographic high in a semi-arid sedimentary basin: Interactions between fluvial erosion, aeolian erosion and aeolian transport

Large-scale aeolian erosion features such as pans usually develop upon a relatively homogeneous erodible sedimentary rock substratum and show simple concave morphologies. However, some erosional depressions in semi-arid to arid settings more complex geological contexts, associating basins outcrops of non-erodible basement. In basins, the geomorphic evolution is controlled by interplay between processes fluvial deposition (especially finer sediment fraction ephemeral lakes) deflation. The occurrence basement within region overall deflation complicates drainage systems wind-flow patterns. Both are liable evolve rapidly through time their interactions remain poorly understood. this study, we use detailed geomorphological analysis, including mapping sand-motion direction 16,300 km2 Tsagaan Els depression (Gobi Desert, Mongolia) well situ-produced cosmogenic 10Be 26Al based quantitative constraints, propose conceptual model for morphologic geologically basins. Based on theoretical studies patterns around obstacles, demonstrate that erosion-resistant highs inside basin induces localization preferential zones carving large-scale relief. enhanced form sub-depocenters controlling local mobilize clastic material transport it zone. These river frequently captured neighboring streams, which creates unstable conditions deposition. Such rapid modifications topography affect hydrogeologic structure may impact potential sediment-hosted mineral deposits.