Large-number detrital zircon U-Pb ages reveal global cooling caused formation of Chinese Loess Plateau during Late Miocene
- 1Frontiers Science Center for Critical Earth Material Cycling, School of Geography and Ocean Science, Nanjing University, Nanjing, China.
- 2Department of Geological Sciences, University of Texas at Austin, Austin, USA
- 3Department of Geography, Geology and Environment, University of Hull, Hull, UK.
- 4Department of Earth Sciences, Uppsala University, Uppsala, Sweden
- 5MOE Key Laboratory of Western China’s Environmental Systems, Lanzhou University, Lanzhou, China
- 6Frontiers Science Center for Critical Earth Material Cycling, School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
The formation of the unique landscape of Chinese Loess Plateau (CLP) is debated because of uncertainties on dust provenance and transport pathways. We present a detailed quantitative estimation of dust source contributions of the CLP, based on more than 37,100 detrital zircon U-Pb ages, combined with mineral assemblages and isotope analyses. Our results reveal that the CLP was stepwise formed by ~8 Ma, and is mainly composed of material from Northeastern Qinghai-Tibet Plateau (NQTP), with increased dust contributions from NQTP occurring at ~2.5 Ma and ~1.2 Ma, and the CLP was formally established. We infer that these changes were driven by stepwise global cooling, which induced aridification and enhanced silt production in glaciated high mountains, the NQTP, as well as dust ablation in the expanded arid regions. We propose that the global cooling, rather than regional tectonic deformation, was the main driver of the formation and evolution of the CLP.
How to cite: Zhang, H., Lu, H., He, J., Xie, W., Wang, H., Zhang, H., Breecker, D., Bird, A., Stevens, T., Nie, J., and Li, G.: Large-number detrital zircon U-Pb ages reveal global cooling caused formation of Chinese Loess Plateau during Late Miocene, The warm Pliocene: Bridging the geological data and modelling communities, Leeds, United Kingdom, 23–26 Aug 2022, GC10-Pliocene-11, https://doi.org/10.5194/egusphere-gc10-pliocene-11, 2022.
