The Rheological boundary layer and its implications for the difference between the thermal and seismic lithospheric bases of the North China Craton

doi:10.6038/cjg20140106

	The Rheological boundary layer and its implications for the difference between the thermal and seismic lithospheric bases of the North China Craton
	He Li-Juan
刊名	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
	2014
卷号	57 期号:1 页码:53-61
关键词	Rheological boundary layer Thermal lithosphere Seismic lithosphere Asthenospheric viscosity North China Craton
ISSN号	0001-5733
DOI	10.6038/cjg20140106
英文摘要	The 2D thermal conductive/convective model indicates that a transition layer exists between the conductive solid lithosphere and the convective fluid asthenosphere, which is named as the rheological boundary layer (RBL). Conduction and convection both transfer heat within this region. The thickness of the RBL is mainly controlled by the asthenospheric viscosity (eta), but not or slightly influenced by the thickness and thermal regime of the solid lithosphere. RBL thins in direct proportion to lowering of lg(eta) when eta decreases from 1 x 10(21) Pa . s to 1 x 10(19) Pa . s. The existence of RBL results in the difference between the thermal and seismic lithospheric bases. A difference of 70 similar to 90 km is indicated by comparison between the thermal and seismic lithospheric thicknesses of global typical cratons, which verifies the existence of RBL. Such difference also occurs in the North China Craton, but decreases from similar to 80 km in the Ordos to similar to 20 km in the Bohai Bay basin. This phenomenon implies an eastward thinning trend of RBL thickness, suggesting the asthenospheric viscosity decreases from west to east. It is probably related to the low-viscosity big mantle wedge formed by the stagnant Pacific slab at the transition zone, and confirms from one side the influence of Pacific subduction on destruction of the North China Craton.
语种	英语
出版者	SCIENCE PRESS
WOS记录号	WOS:000330601900006
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/85497]
专题	中国科学院地质与地球物理研究所
通讯作者	He Li-Juan
作者单位	Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	He Li-Juan. The Rheological boundary layer and its implications for the difference between the thermal and seismic lithospheric bases of the North China Craton[J]. CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,2014,57(1):53-61.
APA	He Li-Juan.(2014).The Rheological boundary layer and its implications for the difference between the thermal and seismic lithospheric bases of the North China Craton.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,57(1),53-61.
MLA	He Li-Juan."The Rheological boundary layer and its implications for the difference between the thermal and seismic lithospheric bases of the North China Craton".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 57.1(2014):53-61.