Dust storms and Chinese loess sources over the last 22 million years

Atmospheric dust is one of the most crucial and poorly understood components of the climate system. Loess deposits on the Chinese Loess Plateau represent one of the longest and most continuous atmospheric dust sinks on the planet, punctuated by rapid changes in dust source and accumulation. However, despite decades of research, the sources of the Quaternary/Neogene loess in China are poorly constrained. This project is the first to utilise single-grains of various heavy minerals in an attempt to constrain the sediment sources of Chinese loess and deserts and so gauge the controls on dust emission over the last 22 million years and over short sub-millennial timescales. The project utilises detrital zircon U-Pb age spectra, fission-track and Hf, as well as geochemical and age data from other minerals These are also compared to age and petrological data from source rocks in north China in an attempt to pin point the sources of the vast quantities of aeolian sediment in China. The project has already highlighted that multiple sources are likely feeding the loess deposits, with abrupt shifts in source over short timescales. There is no direct evidence of one particular single desert source for the dust, but recent findings suggest the Yellow River and erosion of NE Tibet may be critical in dust availability. The project will attempt to upick these sources through time.