气候变化领域集成服务门户(CCPortal): A top-down control on upper crustal inheritance on the south-eastern Tibetan Plateau

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DOI	10.1016/j.tecto.2023.229992
	A top-down control on upper crustal inheritance on the south-eastern Tibetan Plateau
	Di, Qingyun; Zhang, Kun; Xue, Guoqiang; An, Zhiguo; Fu, Changmin; Guo, Wenbo; Zhang, Sanmin
发表日期	2023
ISSN	0040-1951
EISSN	1879-3266
卷号	863
英文摘要	Mantle tectonics, such as asthenospheric upwelling and lithospheric decoupling, usually controls subsequent fluid formation and migration from deep to shallow levels in the lower lithosphere and promotes rock failure and deformation. Based on the concept whereby the fluid migration location defines the structural inheritance, we aim to relate crustal processes to mantle tectonics using fluids revealed by a new magnetotelluric (MT) array across the Ailao Shan-Red River belt. As imaged via a 3D resistivity model, two lower-lithospheric conductive anomalies are determined as consistent with the Dian-Qiong (DQ) suture and Song Da (SD) belt and interpreted to contain interconnected melt. Because potassic magmatism was enabled by partial melting in the lower lithosphere, we could infer that the DQ and SD have reworked as the major fluid migration channels. Fluid migration is considered to drive lithospheric decoupling at a low-viscosity conductive layer, which is inferred feeding by aqueous and melt fluids originating from the two channels and diffusing at depths from 15 to 20 km. Constrained by the geochronology results, this weak layer could have provided convenience to induce the entirely upper crustal translation-rotation within the time interval between potassic magmatism and strike-slip of the Red River fault. This translation-rotation process is inherited from the underlying mantle processes and may further be remotely affected by the upper crustal movement of the Tibetan Plateau, conforming with the crustal rotation observed to the north of our study region. This work provides a compelling example of the tectonic control of the mantle on inherited responses in the crust. Plain Language Summary Crustal deformation is usually controlled by mantle tectonic processes, especially the southeastern Tibetan Plateau. Some models have proposed that lithospheric shearing and lower-crustal flow have controlled the crustal deformation in the Cenozoic. However, crustal rotation models show less possibility of a channel flow and relate the crustal deformation to the remote effect of India-Asia collision. Our study investigates above hypotheses by imaging the electrical resistivity of rocks beneath the major Red River Fault area in southeastern Tibet, using magnetotelluric data with high quality in a dense array. The lithosphere of the study area is interpreted to have been divided into two horizontal systems by a fluid diffusion layer at the bottom of upper crust. Resistivity low in the lower lithosphere is inferred due to partial melting of deep lithosphere and reworking of the paleo sutures in the Late Cenozoic, which have spread at the bottom of upper crust. Rather than the channel flow, this fluid migration process sensitively reflected in our model relates the mantle tectonics to crustal rotation by providing rheological conditions. We, hence, propose an inherited structure model featured by lithospheric decoupling and upper-crustal translation-rotation that may occur before the major strike-slip event.
关键词	Ailao Shan -Red River fault belt 3D geo-electrical model from magnetotelluric sounding Suture reworking Upper crustal translation -rotation process
英文关键词	RIVER SHEAR ZONE; INDO-CHINA; ELECTRICAL-CONDUCTIVITY; GEOELECTRIC STRUCTURE; BENEATH; DEFORMATION; YUNNAN; SUBDUCTION; COLLISION; MANTLE
WOS研究方向	Geochemistry & Geophysics
WOS记录号	WOS:001058641700001
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/283783
作者单位	Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS; Chinese Academy of Sciences; China Geological Survey; Chinese Academy of Geological Sciences; Ministry of Natural Resources of the People's Republic of China; Ministry of Natural Resources of the People's Republic of China; China Geological Survey; Institute of Geology, Chinese Academy of Geological Sciences; Chinese Academy of Geological Sciences
推荐引用方式 GB/T 7714	Di, Qingyun,Zhang, Kun,Xue, Guoqiang,et al. A top-down control on upper crustal inheritance on the south-eastern Tibetan Plateau[J],2023,863.
APA	Di, Qingyun.,Zhang, Kun.,Xue, Guoqiang.,An, Zhiguo.,Fu, Changmin.,...&Zhang, Sanmin.(2023).A top-down control on upper crustal inheritance on the south-eastern Tibetan Plateau.TECTONOPHYSICS,863.
MLA	Di, Qingyun,et al."A top-down control on upper crustal inheritance on the south-eastern Tibetan Plateau".TECTONOPHYSICS 863(2023).