Source-To-Sink Aeolian Fluxes From Arid Landscape Dynamics in the Lut Desert

Abstract

We analyze major landforms of the Lut Desert in Iran to provide a comprehensive source-to-sink picture of aeolian systems on time scales from decades to millions of years. We map the modern sandflows, along which we evaluate the volume and chronology associated with the excavation of mega-yardangs upwind and the formation of giant dunes downwind. Sediment discharges deduced from long-term erosion and deposition are of the same order of magnitude (105–106 m3 yr−1) as short-term and medium-term sand discharges derived from wind data and dune morphodynamics. At the scale of the internal aeolian sediment-routing system of the Lut, we establish an overall sediment budget constrained by the joint development of the erosional and depositional landforms. Our findings thus quantify the geomorphic controls of aeolian processes on arid landscapes at multiple length and time scales, while providing information on mass exchanges between continents and atmosphere.