气候变化领域集成服务门户(CCPortal): Deep electrical resistivity structure across the Gyaring Co Fault in Central Tibet revealed by magnetotelluric data and its implication

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DOI	10.1016/j.tecto.2021.228835
	Deep electrical resistivity structure across the Gyaring Co Fault in Central Tibet revealed by magnetotelluric data and its implication
	Xue S.; Chen Y.; Liang H.; Li X.; Liang X.; Ma X.; Lu Z.; Bai D.; Yan Y.
发表日期	2021
ISSN	00401951
卷号	809
英文摘要	As one of the most prominent deformation features on Tibetan plateau, a series of N-S systematic rifts and V-shaped conjugate strike-slip faults are well developed in central-southern Tibet. However the mechanism for the formation of the rifts and conjugate strike-slip faults is still controversial. An east-west trending magnetotelluric (MT) array has been operated across the Gyaring Co Fault (GCF) at the northern end of the Xainza-Dingjye Rift (XDR) in Lhasa block. Three-dimensional (3-D) inversions are employed to image lithospheric resistivity structure. Combined with the previous north-south MT 3-D inversion result, electrical resistivity models reveal obvious conductive layer in the mid-to-lower crust beneath the XDR and apparent resistivity change in the vicinity of the GCF. The calculated depth-integrated conductivity shows that the weak mid-to-lower crust (~30 km- ~ 60 km) characterized by high conductance (≥ ~10,000 S) and melt fraction of ~5–13%, is mainly distributed between the Indus-Yarlung suture (IYS) and the GCF, whereas the relatively rigid crust characterized by low conductance (≤ ~2000 S) and melt fraction of ~2–4% appears to the northeast of the GCF. The weak mid-to-lower crust in southern Tibet and the abrupt difference in the resistivity characteristics of the mid-to-lower crust in the vicinity of the GCF, suggest the formation of the rifts in Lhasa block is closely associated with the weak mid-to-lower crust. Taken together with the upper mantle seismic features, the weak mid-to-lower crust is believed to be attributed to the underplated Indian plate. An alternative geodynamic model is presented to respond to the eastward extrusion during the ongoing N-S convergence between the Indian and Eurasian plates, that the rigid crust in central Tibet is sandwiched by the weak mid-to-lower crust in southern and northern Tibet, and the rifts form above the weak mid-to-lower crust, whereas the conjugate strike-slip faults develop on the rigid crust in central Tibet. © 2021 Elsevier B.V.
关键词	Conjugate strike-slip fault E-W extension Magnetotellurics (MT)Rift Tibet
英文关键词	Cobalt; Electric conductivity; Geodynamics; Magnetotellurics; Plates (structural components); Strike-slip faults; Apparent resistivity; Conductive layer; Deformation feature; Electrical resistivity structures; Geodynamic modeling; Magnetotelluric data; Resistivity structure; Threedimensional (3-d); Fault slips; deformation; electrical resistivity; Eurasian plate; extensional tectonics; fault zone; formation mechanism; geodynamics; Indian plate; lithospheric structure; lower crust; magnetotelluric method; rift zone; strike-slip fault; upper mantle; China; Qinghai-Xizang Plateau
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/208100
作者单位	Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources, Institute of Geology, Chinese Academy of Geological Sciences, Beijing, 100037, China; State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China; Innovation Academy for Earth Science, Chinese Academy of Sciences, Beijing, 100029, China; School of Earth Science and Geological Engineering, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
推荐引用方式 GB/T 7714	Xue S.,Chen Y.,Liang H.,et al. Deep electrical resistivity structure across the Gyaring Co Fault in Central Tibet revealed by magnetotelluric data and its implication[J],2021,809.
APA	Xue S..,Chen Y..,Liang H..,Li X..,Liang X..,...&Yan Y..(2021).Deep electrical resistivity structure across the Gyaring Co Fault in Central Tibet revealed by magnetotelluric data and its implication.Tectonophysics,809.
MLA	Xue S.,et al."Deep electrical resistivity structure across the Gyaring Co Fault in Central Tibet revealed by magnetotelluric data and its implication".Tectonophysics 809(2021).