Thermoluminescence chronology of sand profiles in the Mu Us Desert, China

Abstract

Thermoluminescence (TL) is used to calculate the ages of two sand–loess profiles in the marginal zone of the Mu Us Desert, China. Alternating units of dune sand and loess with palaeosols in the two profiles imply episodes of dune formation separated by periods of loess accumulation and pedogenesis. Our results indicate that there are three layers of dune sand intercalated in sediments of the last full glacial cycle, suggesting the occurrence of three arid episodes during this time. The first arid episode within this period occurred between <75 and ∼55 ka, broadly corresponding to marine oxygen isotope Stage 4. The second arid episode, with a TL age around 48 ka, can be correlated with part of Stage 3. The latest arid episode occurred between <27 and ∼10 ka, broadly coincident with Stage 2. These periods of dune activity in northern China are compared with records of aeolian influx from deep-sea cores and the Vostok ice core, and with continental dune activity in other regions.