Large-number detrital zircon U-Pb ages reveal global cooling caused formation of Chinese Loess Plateau during Late Miocene

<p>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.</p>