Loess‐Like Dust Appearance at 40 Ma in Central China

Asian mineral dust has been studied extensively for its role in affecting regional-to global-scale climate and deposits, which enable reconstructing atmospheric circulation the past. However, timing origin of deposits remain debated. Numerous loess records have reported across continent with ages varying from Miocene to Eocene linked various mechanisms including global cooling, Tibetan Plateau uplift retreat inland proto-Paratethys Sea. Here, we study terrestrial mudrocks Xining Basin central China use nonparametric end-member analysis grain-size distributions identify a loess-like component appearing record at 40 Ma. This is coeval onset high-latitude orbital cycles shift predominant steppe-desert vegetation as recognized by previous studies same record. Furthermore, derive wind directions eolian dune suggest northwesterly winds, similar modern-day winter monsoon driven high pressure system developing over Siberia. We propose that observed shifts Ma reflect Siberian High interacting westerly derived moisture obliquity timescales promoting storms aridification China. The suggests may triggered increased continentality due retreating Sea