Expanding Processes of the Qinghai-Tibet Plateau during Cenozoic: An Insight from Spatio-Temporal Difference of Uplift

• 责任者：Wang Guocan (State Key Laboratory of Geological Processes and Mineral Resources ; China University of Geosciences ; Wuhan 430074 ; China) ; Zhang Kexin
• 刊名：Earth Science
• 出版年：2010
• 卷期：35(5)
• 关键词：隆起 ; uplifts ; 高原 ; plateaus ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.713-727
• 图表：1 illus., 89 refs.
• 分类号：0300
• issnNo：ISSN1000-2383
• isbnNo：CN42-1233/P

In this paper the authors deduce the expanding and forming processes of the Qinghai-Tibet Plateau by summarizing the spatio-temporal difference of uplift during Cenozoic. The uplift in the Paleocene-Eocene (65~35 Ma) mainly showed rock uplift driven by thrusting in different crust levels. The major denudation areas included the Tianshuihai, the Qilian Shan, Songpan-Ganzi-Bayan Har and Gangdise, etc. There appeared alluvial-pluvial plain with low elevation in the Qiangtang-Hoh Xil-Qaidam and Xining-Linxia areas, and maritime space in the western Kunlun and Himalaya areas. In the Late Oligocene-Early Miocene (25~17 Ma), intensive thrusting induced increased crust thickness in the southern Tibet (including the Gangdese and the northern Himalayan belt). Then in about 17~12 Ma, crust isostatic compensation drove the southern Tibet to reach the current high elevation. Foreland basin developed in the Qiangtang-Hoh Xil area, and basin-range lelief emerged in the northern margin of the Qinghai-Tibetan Plateau during the late Oligocene-early Miocene. In the middle-late Miocene (13-7 Ma), centering in the southern Tibet (the Gangdise-northern Himalayan belt), the plateau grew and expanded northwardly. The basin in the Qiangtang-Hoh Xil area uplifted regionally and reached quite high altitude. In the northern margin of the Qinghai-Tibetan Plateau, a series of mountains popped up to the basin. The modern basin-range relief formed by and large but still kept lower average attitude. Since Pliocene, the plateau has been expanding northward rapidly.