Tracing the Provenance of Long-Range Transported Dust Deposition in Cryospheric Basins of the Northeast Tibetan Plateau: REEs and Trace Element Evidences

Based on cryoconite and snow dust samples collected from various glaciers and snowpacks in northeast Tibetan Plateau (NETP) margin and surrounding areas, this study investigated the rare earth element (REE) and trace element composition of long-range transported (LRT) dust in glacier surfaces at the NETP locations, in order to trace its source areas and the transport over the region. Results showed that the deposited dust in NETP mainly originated from the adjacent Qaidam Basin, Badain Jaran and Taklimakan Deserts based on the similarity in (La/Sm)(N), Th/Yb-N and Nb/Yb-N ratios. However, most samples collected at Miaoergou Glacier (MG) located in the Tianshan Mountains showed very different rare earth elements (REEs) ratios from the above locations attributed to the dominant contribution of LRT dust emitted by the southern Gobi Deserts. We found that large central Asian deserts rarely contributed LRT dust to Yuzhufeng (YG) in the hinterland Tibetan Plateau (TP). Taking the region as a whole, it was found that most of the glacier and snowpacks showed mixed dust sources and inputs from different parts of surrounding central Asian deserts that are characterized by different mineralogical settings. Geochemical data indicated that the NETP region acts as an important channel for aeolian transport from large Asian deserts into Loess Plateau and eastern regions, with atmospheric circulations bringing plenty of dust particles deposition to the high-altitude glacier surface in NETP margin. This work is of great importance in providing a new complete view of LRT aeolian emission and transport over the NETP region