Structural kinematics, metamorphic P-T profiles and zircon geochronology   across the Greater Himalayan Crystalline Complex in south-central Tibet:   implication for a revised channel flow

doi:10.1111/jmg.12036

CORC > 北京大学 > 地球与空间科学学院

	Structural kinematics, metamorphic P-T profiles and zircon geochronology across the Greater Himalayan Crystalline Complex in south-central Tibet: implication for a revised channel flow
	Wang, J. M. ; Zhang, J. J. ; Wang, X. X.
刊名	journal of metamorphic geology
	2013
关键词	channel flow critical taper Greater Himalayan Crystalline Complex P-T profiles zircon geochronology MAIN CENTRAL THRUST EASTERN NEPAL HIMALAYA DETACHMENT SYSTEM INVERTED METAMORPHISM EVEREST REGION PATH DISCONTINUITY TECTONIC EVOLUTION NUMERICAL-MODELS LANGTANG VALLEY LEADING-EDGE
DOI	10.1111/jmg.12036
英文摘要	A specific question about the Himalayas is whether the orogeny grew by distributed extrusion or discrete thrusting. To place firm constraints on tectonic models for the orogeny, kinematic, thermobarometric and geochronological investigations have been undertaken across the Greater Himalayan Crystalline Complex (GHC) in the Nyalam region, south-central Tibet. The GHC in this section is divided into the lower, upper and uppermost GHC, with kinematically top-to-the-south, alternating with top-to-the-north shear senses. A new thrust named the Nyalam thrust is recognized between the lower and upper GHC, with a 3 kbar pressure reversion, top-to-the-south thrust sense, and was active after the exhumation of the GHC. Peak temperature reached similar to 749 degrees C in the cordierite zone, and decreased southwards to 633-667 degrees C in the kyanite and sillimanite-muscovite zones, and northwards to greenschist facies at the top of the South Tibetan Detachment System (STDS). Pressure at peak temperature reached a maximum value in the kyanite zone of 9.0-12.6 kbar and decreased northwards to similar to 4.1 kbar in the cordierite zone. Zircon U-Pb ages of a sillimanite migmatite and an undeformed leucogranite dyke cutting the mylonitized rocks in the STDS reveal a long-lived partial melting of the GHC, which initiated at 39.7-34 Ma and ceased at 14.1 Ma. Synthesizing the obtained and collected results, a revised channel flow model is proposed by considering the effect of heat advection and convection by melt and magma migration. Our new model suggests that distributed processes like channel flow dominated during the growth of the Himalayan orogen, while discrete thrusting occurred in a later period as a secondary process.; Geology; SCI(E); EI; 9; ARTICLE; 6; 607-628; 31
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/155611]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Wang, J. M.,Zhang, J. J.,Wang, X. X.. Structural kinematics, metamorphic P-T profiles and zircon geochronology across the Greater Himalayan Crystalline Complex in south-central Tibet: implication for a revised channel flow[J]. journal of metamorphic geology,2013.
APA	Wang, J. M.,Zhang, J. J.,&Wang, X. X..(2013).Structural kinematics, metamorphic P-T profiles and zircon geochronology across the Greater Himalayan Crystalline Complex in south-central Tibet: implication for a revised channel flow.journal of metamorphic geology.
MLA	Wang, J. M.,et al."Structural kinematics, metamorphic P-T profiles and zircon geochronology across the Greater Himalayan Crystalline Complex in south-central Tibet: implication for a revised channel flow".journal of metamorphic geology (2013).