Geochemical studies on the source region of Asian dust

Abstract

The North China and the neighbouring Mongolia in Asian Interior is characterized by extremely dry climate, resulted in one of the world's major dust emission centres. Deciphering the source region of Asian dust is critical for revealing the mechanism of the dust production, interpreting the paleo-environmental records of eolian deposits, predicting the overall environmental effects of dust, and setting the strategies for the control of contemporary dust storms. This paper summarizes the geochemical methods applied to the source tracing of Asian dust. Nd-Sr isotopes were the most extensively studied source tracer of Asian dust and have been successfully applied in many cases. Geochemistry of detrital monomineral shows great theoretical advantages in source tracing and deserves further studies. The short-range transportation of Chinese loess with direction similar to that of the prevailing near surface wind is revealed. Source tracing also shows that the Asian dust has two ultimate material sources from the northern margin of the Tibetan Plateau and the Central Asian Orogen, which confirms the importance of mountain processes in the production of silt eolian particles. Based on the recent progresses on the source tracing of Asian dust, discussions are expanded on the natural background of Asian dust storms and potential anthropogenic influence, the materials evolution of the source regions of Asian dust and its relationships with climate changes and Tibetan uplift, and the role of Tibetan uplift in the Asian dust system. desert, loess, Asian dust, dust storm, Tibetan Plateau Citation:Chen J, Li G J. Geochemical studies on the source region of Asian dust.

Long-term Pleistocene aridification and possible linkage to high-latitude forcing: New evidence from grain size and magnetic susceptibility proxies from loess-paleosol record in northeastern China

“…Because the NYZG section is located close to the sandy deserts in NE China (Fig. 2a), and has been demonstrated to be sourced from these areas (Xie et al, 2012;Chen and Li, 2011), the loess samples are enriched in sand-sized particles associated with short-distance transport, which accords with their proximal provenance. Therefore, we infer that variations in the content of the sand-fraction (N 63 μm) in the NYZG section should be sensitive to migration of the desert margin and to wet-dry climate oscillations within the dust sources areas, as is the case for the loess deposits in the northern CLP.…”

“…Provenance studies using both using Nd-Sr isotopic composition (Chen and Li, 2011;Zhao et al, 2014) and detrital zircon U-Pb age analyses (Xie et al, 2012) have demonstrated that the major source areas of the loess deposits in NE China are likely to be the upwind Horqin and Otindag sandy deserts. Therefore, the loess and adjacent sandy deserts Catena 154 (2017) [21][22][23][24][25][26][27][28][29][30][31][32] in NE China can be regarded as a coupled system, with dust source and sink formed under a semi-arid climate, which is quite distinct from the loess deposits of the CLP and their corresponding sources areas in northwestern and central China.…”

A high-resolution multi-proxy record of late Cenozoic environment change from central Taklimakan Desert, China

“…Washington et al, 2003;Zhang et al, 2003;Chen and Li, 2011). In the central Taklimakan Desert, continuous late Cenozoic sequences with intercalated in-situ aeolian dune sand preserve direct evidence for the Asian desertification.…”

Influence of the Tibetan Plateau uplift on the Asian monsoon-arid environment evolution

“…The terrain of Tianshan and Mongolia also uplifted considerably during this period [5,69], and even in the late Pliocene tectonic uplift still occurred in the northern TP [6,73]. Some scholars believed that the uplift of northern TP could produce the denudation at the northern edge of the plateau, and thus provide dust material for the Asian dust source region, contributing to promoting Asian dust cycle and increasing the downstream dust flux [5,86]. Existing eolian records from oceans and continents showed that since the middle Pliocene the aridification of inland Asia was intensified and the ancient dust flux followed a significantly increasing trend at the tectonic time scale.…”