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DOI	10.1016/j.earscirev.2019.02.010
	The importance of a weak mid-lithospheric layer on the evolution of the cratonic lithosphere
	Wang Z.; Kusky T.M.
发表日期	2019
ISSN	00128252
起始页码	557
结束页码	569
卷号	190
英文摘要	Seismically detectable discontinuities at mid-depths of some cratonic lithospheric mantle define mid-lithosphere discontinuities (MLD), demonstrating that the lithospheric mantle is layered. The genesis and strength of the MLD are still in debate, most proposed models suggest the MLD is likely not weaker than the normal lithosphere, whereas other proposed models suggest that some metasomatised MLD rocks are weaker than the normal lithospheric mantle rocks. Thus, the weak MLD is likely a weakly-coupled layer at mid-depths in some cratonic lithosphere blocks, possibly influencing their stabilities. We assess the geodynamic significance of the MLD using geodynamic modeling. We propose that a weak MLD, with lower effective viscosity, can be connected to thinned cratonic margins during the evolution of some cratons and form continuously connected weak zones from cratonic margins to craton interiors, which can lead to lithospheric thinning or removal by extension, basal drag, delamination, thermochemical erosion, and other actions. Through analyzing different scenarios, we propose that some samples of weak MLDs can be found in a composite ophiolite profile formed on the Precambrian Karelian continental margin, with both continental and oceanic lithosphere, which is supported by chronological, petrological, and structural architectures of the profile. This creates new opportunities to directly study the properties of the MLD, which could help understand and settle the controversies on the origin of the MLD and its physical, chemical, and geophysical properties. © 2019 Elsevier B.V.
关键词	Basal drag Composite ophiolite profile Delamination Extension Mid-lithosphere discontinuity Oceanic plateau
英文关键词	craton; delamination; discontinuity; extension; geodynamics; lithosphere; ophiolite; plateau
语种	英语
来源期刊	Earth Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203585
作者单位	State Key Lab of Geological Processes and Mineral Resources, Center for Global Tectonics, School of Earth Sciences, China University of Geosciences, Wuhan, China; Three Gorges Research Center for Geohazards, China University of Geosciences, Wuhan, China; Department of Geological Engineering, Middle East Technical University, Ankara, Turkey
推荐引用方式 GB/T 7714	Wang Z.,Kusky T.M.. The importance of a weak mid-lithospheric layer on the evolution of the cratonic lithosphere[J],2019,190.
APA	Wang Z.,&Kusky T.M..(2019).The importance of a weak mid-lithospheric layer on the evolution of the cratonic lithosphere.Earth Science Reviews,190.
MLA	Wang Z.,et al."The importance of a weak mid-lithospheric layer on the evolution of the cratonic lithosphere".Earth Science Reviews 190(2019).