COUPLING OF MIDDLE MIOCENE-PLIOCENE RAPID UPLIFT OF THE NORTHERN TIBET PLATEAU AND DRYING OF CENTRAL ASIA AND GLOBAL COOLING

The uplift of the Tibetan Plateau (TP) has long been hypothesized to be linked with the deccication of Central Asia and global cooling. However, its testifying has suffered from lacking convincing records. Here we synthesized records from recent progress of uplift of the northern TP and aridification of the Asian inland and our new deep drilling of the Linxia Cenozoic sediments in the northeastern TP. The results show that the northern TP underwent an accelerated stepwise rapid uplift at about 15Ma, 8-7Ma, 3.6Ma and 1.2-0.5Ma. This caused a synchronous accelerated erosion of the northern TP and drying of the Asian inland, manifesting as enhanced dust sedimentation, loess accumulation and desert expansion, as well as the ecological transformation from forest via forest-steppe to steppe and desert. Numerical modeling confirmed the linkage between the uplift of the northern TP and drying of the Asian inland. This linkage occurred also with global stepwise cooling since those times, which were accompanied by onsets of the southeastern Antarctic ice sheet and Arctic ice sheet.