Sedimentology Record And Geomorphology Response For The Uplift Of Eastern Margin Of Tibet Plateau In The Late Cenozoic

The uplift in upper Cenozoic along the eastern margin of the Tibetan Plateau gives important evidences on sediment and geomorphology,and this article is to recover some of the qualities and characters of the uplift through analyzing the sediment record in Chengdu Basin and the present geomorphology along the eastern margin of the Tibetan Plateau.The distribution of Dayi formation is mainly along between the Longmenshan mountains and Chengdu Basin which sorting is very bad and the biggest size of the conglomerate is bigger than lm.Dayi formation is thought to be the result of uplift in late Cenozoic of the eastern margin of Tibetan Plateau and record the process of the uplift faithfully .Therefore, In the deposition record research, we take the Dayi formation as the key point and mainly launch the research from following several methods; â‘ sedimentology methods with ingredient statistics and contrast of conglomerates, appraisal and contrast of sandstone thin section, sizing test contrast, heavy mineral analysis, clay mineral X diffraction analysis and spore powder analysis; â‘¡Geochemistry analysis method; â‘¢mathematics method with Principal component analysis and sediment flux computation; â‘£Chronology method. Through the research techniques and verify mutually ,We obtain following understanding.â‘ Minjiang River changed course to pour into the Chengdu basin which is after the initial period of Dayi conglomerate deposition .â‘¡Miaopo and eastern Xiongpo exposures of conglomerates are controlled by paleo Qingyi jiang and Qingyi jiang drainage area is stable .â‘¢In the Dayi conglomerate deposition period,the erosion rateof southern Longmen shan...