Late Cenozoic geology and paleoenvironmental change on the eastern margin of the Qinghai-Tibet Plateau.

Abstract: A complete sequence of late Cenozoic lacustrine deposits, loess, red clay and glacial deposits is developed on the eastern margin of the Qinghai-Tibet Plateau. Deposits of different origins recorded rich information of paleoenvironmental change since the late Cenozoic. The Pliocene lacustrine deposits at Xigeda occurred at 4.2-2.6 Ma BP. There were nine stages of cold-warm climatic and environmental changes. Eolian deposition in western Sichuan began at 1.15 Ma BP recorded fourteen continuous paleomonsoonal cycles. Red clay in the Chengdu basin recorded five stages of paleoclimatic change since 1.13 Ma BP. There was a 4.3 Ma old glaciation on the eastern margin of the Qinghai-Tibet Plateau. During the Quaternary, there appeared five extreme paleoclimatic events, corresponding to five glaciations.