Eastward migration of the Qaidam basin and its implications for Cenozoic evolution of the Altyn Tagh fault and associated river systems

doi:10.1130/B25778.1

	Eastward migration of the Qaidam basin and its implications for Cenozoic evolution of the Altyn Tagh fault and associated river systems
	Wang, E ; Xu, FY ; Zhou, JX ; Wan, JL ; Burchfiel, BC
刊名	GEOLOGICAL SOCIETY OF AMERICA BULLETIN
	2006-03-01
卷号	118 期号:3-4 页码:349-365
关键词	Tibetan plateau Qaidam basin depocenter eastward migration longitudinal river
ISSN号	0016-7606
DOI	10.1130/B25778.1
文献子类	Article
英文摘要	The Qaidam basin is the largest Cenozoic intermontane basin within the Tibetan plateau, bounded by the Qilian Shan range to the north, the East Kunlun range to the south, the Altyn Tagh range to the west, and the Ela Shan range to the east. Its deposits consist of nonmarine sedimentary rocks, with a maximum thickness exceeding 43,400 in. Modern sedimentation mainly takes place along the marginal areas of the basin, where alluvial fans are formed along a series of rivers that originate from the surrounding mountains. Nevertheless, drilling, sedimentary, and seismic data reveal that the depocenter of the basin during much of Cenozoic time was not developed as foreland basins of the Qilian Shan belt to the north and the East Kunlun belt to the south, but instead the depocenter was in the center of the western part of the basin and had a northwest-southeast trend that shifted eastward similar to 380 km during Oligocene to Quaternary time. This indicates that most of the basin sediments were not derived from the surrounding mountain ranges. The results of the fission-track age dating reveal that the rapid uplift of the Yousha Shan anticline bounding the depocenter to the southwest initiated at ca. 31 Ma, indicating that the southeastward shift of the depocenter began at that time, yielding a migration rate for the depocenter of 10.2 min/yr. The northwestern margin of the depocenter of the Qaidam basin lies to the east of the westward prolongation of the Qaidam basin, the Tula trough, a 300-km-long narrow trough flanked by the Altyn Tagh range along the Altyn Tagh strike-slip fault on the north and the East Kunlun thrust belt on the south. The sedimentary and deformational evidence from this region indicates that the Tula trough was formed as a syncline, along which a paleoriver flowed to the east into the Qaidam basin. To the southwest, this river valley merges with the trace of the Altyn Tagh fault. The latter and its westward continuation are interpreted to have extended to the northern margin or the Pamir folded belt north of the western syntaxis of the Himalaya. We propose that most of the sediments within the depocenter of the Qaidam basin were transported from the northern margin of the Pamir folded belt along a progressively lengthening 2000-km-long longitudinal river that developed along the left-lateral Altyn Tagh fault and its western continuation, as the eastward extrusion of the Tibetan plateau took place in Oligocene time. Both the crustal uplift and continuous southeastward aggradations of the sediments carried by the paleo-Kunlun River are interpreted to be the cause for southeastward migration of the depocenter of the Qaidam basin. The longitudinal river disappeared in late Cenozoic time (2-4 Ma) due to stream capture and climate change.
WOS关键词	INDIA-ASIA COLLISION ; TIBETAN PLATEAU ; TECTONIC EVOLUTION ; KINEMATIC MODEL ; KARAKORAM FAULT ; NORTHERN TIBET ; CLIMATE-CHANGE ; CHINA ; DEFORMATION ; SHAN
WOS研究方向	Geology
语种	英语
出版者	GEOLOGICAL SOC AMER, INC
WOS记录号	WOS:000235962700007
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/66414]
专题	中国科学院地质与地球物理研究所
通讯作者	Wang, E
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 2.Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100029, Peoples R China 3.Qinghai Petr Subcorp Petrochina Co Ltd, Dunhuang 736202, Peoples R China 4.Univ Petr, Dept Earth Sci, Beijing 102249, Peoples R China 5.China Seismol Bur, Lab Neotect Chronol, Inst Geol, Beijing 100029, Peoples R China 6.MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA
推荐引用方式 GB/T 7714	Wang, E,Xu, FY,Zhou, JX,et al. Eastward migration of the Qaidam basin and its implications for Cenozoic evolution of the Altyn Tagh fault and associated river systems[J]. GEOLOGICAL SOCIETY OF AMERICA BULLETIN,2006,118(3-4):349-365.
APA	Wang, E,Xu, FY,Zhou, JX,Wan, JL,&Burchfiel, BC.(2006).Eastward migration of the Qaidam basin and its implications for Cenozoic evolution of the Altyn Tagh fault and associated river systems.GEOLOGICAL SOCIETY OF AMERICA BULLETIN,118(3-4),349-365.
MLA	Wang, E,et al."Eastward migration of the Qaidam basin and its implications for Cenozoic evolution of the Altyn Tagh fault and associated river systems".GEOLOGICAL SOCIETY OF AMERICA BULLETIN 118.3-4(2006):349-365.