气候变化领域集成服务门户(CCPortal): Structural evolution of the Neogene Gar Basin, western Tibet: Implications for releasing bend development and drainage patterns

CCPortal

DOI	10.1130/B26566.1
	Structural evolution of the Neogene Gar Basin, western Tibet: Implications for releasing bend development and drainage patterns
	Sanchez, Veronica I.; Murphy, Michael A.; Dupre, William R.; Ding, Lin; Zhang, Ran
通讯作者	Sanchez, VI (通讯作者)
发表日期	2010
ISSN	0016-7606
EISSN	1943-2674
起始页码	926
结束页码	945
卷号	122 期号:5-6
英文摘要	We investigated the interaction among basin-bounding faults, basin fill, and geomorphic features of the southern Gar Basin, one of only two known releasing double-bend basins along the Karakoram fault, to better understand their structural evolution and role in basin development. The southern Gar Basin is bounded by an similar to 44-km-long, N20 degrees W-striking central fault segment flanked by two N40 degrees W-striking segments that parallel the regional strike of the Karakoram fault system. The central fault segment is composed of a system of strike-slip and normal faults that young basinward and incorporate basin fill in their uplifted footwalls. The oldest faults along the extensional portion of the bend are dominantly strike-slip, and they strike similar to 15 degrees W from the main strike of the Karakoram fault. Basin fill is broadly folded about a NNW-trending axis and can be explained by E-SE-directed slip along a listric normal fault. Cross sections across the basin and associated faults suggest the geometry is best described as an extensional flower structure. Forward structural modeling of the intrabasinal faults shows that the system has accommodated similar to 8 km of east-west extension. We interpret the bend to have formed from linking of R and P shears into a through-going principal displacement zone. At shallow levels in the crust (low confining pressures), R shears are exploited; at deeper levels, these faults merge with the principal displacement zone, forming the extensional flower structure geometry. We estimate that the shear zone is 50-35 km wide based on the aerial distribution of P and R shears. Restoration of R shears on the west and east sides of the Gar Valley indicates similar to 55 km of right-lateral separation along the Karakoram fault, which is a minimum slip estimate for the Karakoram fault system.
关键词	KARAKORAM FAULT SYSTEM STRIKE-SLIP FAULTS PULL-APART BASINS ALTYN TAGH FAULT ACTIVE DEFORMATION SOUTHWEST TIBET ALLUVIAL-FAN SHEAR ZONES SOUTHERN INDIA
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000278350800020
来源期刊	GEOLOGICAL SOCIETY OF AMERICA BULLETIN
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/257780
推荐引用方式 GB/T 7714	Sanchez, Veronica I.,Murphy, Michael A.,Dupre, William R.,et al. Structural evolution of the Neogene Gar Basin, western Tibet: Implications for releasing bend development and drainage patterns[J]. 中国科学院青藏高原研究所,2010,122(5-6).
APA	Sanchez, Veronica I.,Murphy, Michael A.,Dupre, William R.,Ding, Lin,&Zhang, Ran.(2010).Structural evolution of the Neogene Gar Basin, western Tibet: Implications for releasing bend development and drainage patterns.GEOLOGICAL SOCIETY OF AMERICA BULLETIN,122(5-6).
MLA	Sanchez, Veronica I.,et al."Structural evolution of the Neogene Gar Basin, western Tibet: Implications for releasing bend development and drainage patterns".GEOLOGICAL SOCIETY OF AMERICA BULLETIN 122.5-6(2010).