气候变化领域集成服务门户(CCPortal): Strong Variability in the Thermal Structure of Tibetan Lithosphere

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DOI	10.1029/2022JB026213
	Strong Variability in the Thermal Structure of Tibetan Lithosphere
	Xia, B.; Artemieva, I. M.; Thybo, H.; Klemperer, S. L.
发表日期	2023
ISSN	2169-9313
EISSN	2169-9356
卷号	128 期号:3
英文摘要	We present a model of thermal lithospheric thickness (the depth where the geotherm reaches a temperature of 1300 & DEG;C) and surface heat flow in Tibet and adjacent regions based on a new thermal-isostasy method. The method accounts for crustal density heterogeneity, is free from any assumption of a steady-state lithosphere thermal regime, and assumes that deviations from crustal Airy-type isostasy are caused by lithosphere thermal heterogeneity. We observe a highly variable lithospheric thermal structure which we interpret as representing longitudinal variations in the northern extent of the subducting Indian plate, southward subduction of the Asian plate beneath central Tibet, and possible preservation of fragmented Tethyan paleo-slabs. Cratonic-type cold and thick lithosphere (200-240 km) with a predicted surface heat flow of 40-50 mW/m(2) typifies the Tarim Craton, the northwest Yangtze Craton, and most of the Lhasa Block that is likely refrigerated by underthrusting Indian lithosphere. We identify a North Tibet anomaly with thin (< 80 km) lithosphere and high surface heat flow (> 80-100 mW/m(2)). We interpret this anomaly as the result of removal of lithospheric mantle and asthenospheric upwelling at the junction of the Indian and Asian slabs with opposite subduction polarities. Other parts of Tibet typically have intermediate lithosphere thickness of 120-160 km and a surface heat flow of 45-60 mW/m(2), with patchy anomalies in eastern Tibet. While different uplift mechanisms for Tibet predict different lithospheric thermal regimes, our results in terms of a highly variable thermal structure beneath Tibet suggest that topographic uplift is caused by an interplay of several mechanisms.
英文关键词	CRUSTAL STRUCTURE BENEATH; WAVE VELOCITY STRUCTURE; ANGLE SEISMIC PROFILE; UPPER-MANTLE; HEAT-FLOW; SOUTHERN TIBET; NORTHEASTERN MARGIN; TECTONIC EVOLUTION; CONTINENTAL CHINA; ADJACENT AREAS
WOS研究方向	Geochemistry & Geophysics
WOS记录号	WOS:000952812000001
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283448
作者单位	Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS; Stanford University; Helmholtz Association; GEOMAR Helmholtz Center for Ocean Research Kiel; China Geological Survey; Chinese Academy of Geological Sciences; China University of Geosciences - Wuhan; Istanbul Technical University
推荐引用方式 GB/T 7714	Xia, B.,Artemieva, I. M.,Thybo, H.,et al. Strong Variability in the Thermal Structure of Tibetan Lithosphere[J],2023,128(3).
APA	Xia, B.,Artemieva, I. M.,Thybo, H.,&Klemperer, S. L..(2023).Strong Variability in the Thermal Structure of Tibetan Lithosphere.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,128(3).
MLA	Xia, B.,et al."Strong Variability in the Thermal Structure of Tibetan Lithosphere".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 128.3(2023).