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DOI	10.1007/s11430-012-4391-6
	Channel flow of the lower crust and its relation to large-scale tectonic geomorphology of the eastern Tibetan Plateau
	Wang XiaoFang; He JianKun
通讯作者	He, JK (通讯作者)
发表日期	2012
ISSN	1674-7313
EISSN	1869-1897
起始页码	1383
结束页码	1390
卷号	55 期号:8
英文摘要	The Tibetan Plateau is a large-scale tectonic geomorphologic unit formed by the interactions of plates. It has been commonly believed that convective removal of the thickened Tibetan lithosphere, or lateral flow of the lower crust beneath the Tibetan plateau plays a crucial role in the formation of the large-scale tectonic geomorphologic features. Recent geological and geophysical observations have provided important evidence in support of the lower crustal channel flow model. However, it remains unclear as how the geometry of lower crustal channel and the lateral variation of crustal rheology within the lower crust channel may have affected spatio-temporal evolution of the tectonic geomorphologic unit of the Tibetan Plateau. Here, we use numerical methods to explore the mechanical relations between the lower crustal channel flow and the tectonic geomorphologic formation around the eastern Tibetan plateau, by deriving a series of governing equations from fluid mechanics theory. From numerous tests, our results show that the viscosity of the channeled lower crust is about (1-5)x10(18) to (1-4)x10(20) Pa s (Pa center dot s) beneath the margin of the eastern Tibetan Plateau, and increases to about 10(22) Pa s beneath the Sichuan Basin and the southern region of Yunnan Province. Numerical tests also indicate that if channel flows of the lower crust exist, the horizontal propagation and the vertical uplifting rate of the eastern Tibetan Plateau margin could be accelerated with the time. Thus, the present results could be useful to constrain the rheological structure of the crust beneath the eastern Tibetan plateau, and to understand the possible mechanics of rapid uplift of the eastern Tibetan Plateau margin, especially since its occurrence at 8Ma as revealed by numerous geological observations.
关键词	SLIP RATES DEFORMATION FAULT EXTENSION EXTRUSION STRENGTH SYSTEM KUNLUN CHINA
英文关键词	channel flow; rheology of the lower crust; tectonic geomorphology; eastern margin of the Tibetan Plateau
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000307255500019
来源期刊	SCIENCE CHINA-EARTH SCIENCES
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/257966
推荐引用方式 GB/T 7714	Wang XiaoFang,He JianKun. Channel flow of the lower crust and its relation to large-scale tectonic geomorphology of the eastern Tibetan Plateau[J]. 中国科学院青藏高原研究所,2012,55(8).
APA	Wang XiaoFang,&He JianKun.(2012).Channel flow of the lower crust and its relation to large-scale tectonic geomorphology of the eastern Tibetan Plateau.SCIENCE CHINA-EARTH SCIENCES,55(8).
MLA	Wang XiaoFang,et al."Channel flow of the lower crust and its relation to large-scale tectonic geomorphology of the eastern Tibetan Plateau".SCIENCE CHINA-EARTH SCIENCES 55.8(2012).