Combined tectonics and climate forcing for the widespread aeolian dust accumulation in the Chinese Loess Plateau since the early late Miocene

Abstract

Currently mechanisms for the onset of the widespread aeolian dust accumulation in the Chinese Loess Plateau since 8–7 Ma remain elusive. In this study, we compile 11 records of climate (14–7 Ma) and tectonic activity of the Tibetan Plateau and its adjacent areas (15–6 Ma). The results suggest that strong tectonic activity in the northeastern Tibetan Plateau has produced massive debris and dust, which was deposited in the piedmont basins and reworked by weathering and fluviolacustrine erosion. At the same time, global cooling and uplift of the Tibetan Plateau over the period of 14–7 Ma intensified the East Asian winter monsoon and westerly winds (westerlies) while weakening the Asian summer monsoon, which led to the spread of dry land vegetation and aridification in interior China. Sediments in the piedmont basins were then exposed in the aridity and transported by the westerlies to the Chinese Loess Plateau and the North Pacific. We suggest that tectonic activity in the northeastern Tibetan Plateau and shifting global climate together triggered the widespread aeolian dust accumulation in the Chinese Loess Plateau and the North Pacific since 8–7 Ma.

Keywords:

• global cooling
• Chinese Loess Plateau
• dust accumulation
• aridification
• Tibetan Plateau
• early late Miocene

Acknowledgements

We are grateful to Jun Tian, Enqing Huang, Weijia Fan, Haowen Dang and Sui Wan for fruitful discussion. We are grateful to the Editor-in-Chief and two anonymous reviewers for their constructive comments.

Additional information

Funding

Funding for this research was provided by the NSFC [grant number 91128208], Shanghai Shu Guang Programme [11SG24], Shanghai Human Development Fund [201336] and State Key Laboratory of Marine Geology [MG20130201].