All mixed up: Using single-grain equivalent dose distributions to identify phases of pedogenic mixing on a dryland alluvial fan

Abstract

The optically stimulated luminescence (OSL) signal from quartz grains is most often used to estimate the depositional age of sediments that were fully bleached during transport and have not been mixed after deposition. However, sediment that is transported fluvially may not have been exposed to sufficient sunlight to bleach the latent OSL signal, while stable land surfaces on which soils are developing will likely be subject to mixing processes such as pedoturbation. In these cases, large equivalent dose (De) datasets derived from individual sand-sized quartz grains can shed light on the depositional and post-depositional histories of sedimentary deposits. Here, we report the results of geoc..