The Sedimentary Record in Northern Qaidam Basin and its Response to the Uplift of the South Qilian Mountain at around 30 Ma

• Published in: Acta geologica Sinica (Beijing) Vol. 87; no. 2; pp. 528 - 539
• Main Authors: Bowen, SONG, Kexin, ZHANG, Ruiming, CHEN, Chaowen, WANG, Mansheng, LUO, Jianyu, ZHANG, Shangsong, JIANG
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.2013; Wiley Subscription Services, Inc; Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China%Institute of Geology and Mineral Resources, China Geological Survey, Xi 'an 710054, China%Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China%State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences,Wuhan 430074, China%Institute of Geology and Mineral Resources, China Geological Survey, Wuhan 430205, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences,Wuhan 430074, China
• Edition: English ed.
• Subjects: Basins; CIW; Early Oligocene; heavy mineral; Mountains; Plate tectonics; Qaidam Basin; uplift of Tibetan Plateau; ZTR指数; 新生代盆地; 柴达木盆地北缘; 沉积记录; 祁连山; 隆升剥蚀; 隆起; 青藏高原东北部; CIW; heavy mineral; Qaidam Basin; uplift of Tibetan Plateau; Early Oligocene
• ISSN: 1000-9515; 1755-6724
• DOI: 10.1111/1755-6724.12066

The thick, Eocene to Pliocene, sedimentary sequence in Qaidam Basin at the northern margin of the Tibetan Plateau records the surface uplift history of the northeastern Tibetan plateau. In this study, we present detailed geochemistry, heavy mineral, and clay mineralogy data of the well preserved sedimentary record in the Dahongou section in the northeast of the Qaidam Basin. The results suggest that the sedimentary sequence recorded a 30 Ma young uplift/unroofing event in the northern edge of the Qaidam Basin, which is characterized by high ZTR index value and chlorite content, and low CIW＇. The results are consistent with previous sedimentological studies of the Qaidam Basin, which indicated rapid increase of the accumulation rates around 30 Ma. Based on past thermochronological data from the mountains around the Qaidam Basin and the accumulation rates of the Cenozoic basins in the northeastern Tibetan Plateau, we infer a regional uplift and denudation event along the northeastern Tibetan Plateau during early Oligocene （-30 Ma）, indicating that the Tibetan Plateau had expanded north-eastward of the study area at that time.