Geochemical characteristics of insoluble dust as a tracer in an ice core from Miaoergou Glacier, east Tien Shan

• Extracting the insoluble dust in Miaoergou ice core, the geochemical characteristics of REEs and Sr–Nd isotopic compositions were discussed in this ice core.
• The aeolian dust in Miaoergou Glacier primarily originates from the deserts of central Asian, Taklimakan and Gobi.
• Ice core records imply that the long range transport of Asian dust contributes much dust to the Greenland regions.

An ice core was extracted from Miaoergou Glacier, east Tien Shan, China. Concentrations of the rare earth elements (REEs) and Sr–Nd isotopic ratios were measured in insoluble dust sampled from the core. The ratios of REEs in insoluble dust were found to have characteristics typical of aeolian deposition, similar to those of sand and loess from Taklamakan. This suggests that the Taklamakan Desert might be an important source of dust reaching the Miaoergou Glacier. Sr (87Sr/86Sr average 0.718014 and range 0.717025 to 0.718958) and Nd (εNd(0) average − 9.1 and range − 9.5 to − 8.5) isotopic compositions in insoluble dust are similar to those of desert sand from Taklamakan and Gobi, suggesting that the Gobi Desert may be another major aeolian source for Miaoergou Glacier. Our results can be compared with Sr–Nd isotopic ratios from Greenland snow and ice, further demonstrating how the dust from Asian deserts contributes a high proportion of aeolian dust in the Greenland region.

In this study, we drilled a shallow ice core in Miaoergou Glacier, which is close to Chinese western deserts. By extracting the insoluble dust with PTFE filter in ice core under clean room conditions, and measuring the concentration of REEs and Sr–Nd isotopic compositions, then, based on the characteristics of REEs and the isotopic ratios of Sr–Nd in insoluble dust, and compared this study with desert sand and loess, the dust provenances were identified. Finally, we discuss the long range transport relationship between Asian dust and Greenland snow and ice cores.Figure optionsDownload as PowerPoint slide