Analyses have been carried out on the lacustrine setting of the Wudaoliang Formation in the Tuotuohe Basin of QinghaiTibet Plateau. The study focuses on information of climate changes reflected by the sedimentary stratigraphic records and investigates the palaeoenvironmemt changes in the plateau in the Miocene. Rock types and sedimentary characteristics of the Wudaoliang Formation were analyzed and flood plain, shallow lacustrine, shore lacustrine and salt lake sedimentary facies were recognized. With reference to the present lacustrine features and the study examples of ancient lakes, the sedimentary origins of the lacustrine carbonates in the study area were discussed. The facies markers in the section and the stratigraphic stacking patterns indicate that the palaeolake experienced three cycles of low lake level to high lake level changes during the deposition of the Wudaoliang Formation. The minimum lake level is marked by the occurrence of the gypsum interval, while the high lake level period is characterized by the deposition of flooding mudstones. The results indicate that the depositional setting of the Wudaoliang Formation was dominated by a drywet climate alternation, lake level change and the fluctuation is mainly influenced by climate with structural subsidence and fault block uplifting as the secondary controlling factors.
QinghaiTibet Plateau, Wudaoliang Formation, sedimentary facies, palaeoevironment
About author: Sun Xia was born in 1983. She is a master candidate of Institute of Sedimentary Geology,Chengdu University of TechnologyAddress:Institute of Sedimentary Geology,Chengdu University of Technology, Chengdu,Sichuan; Postcode:610059; Tel:13693400645。
Cite this article:
. Institute of Sedimentary Geology, Chengdu University of Technology, Chengdu610059, Sichuan[J]. JOURNAL OF PALAEOGEOGRAPHY, 2009, 11(1): 58-68.
. Institute of Sedimentary Geology, Chengdu University of Technology, Chengdu610059, Sichuan[J]. JOPC, 2009, 11(1): 58-68.