文献类型：期刊文献

英文题名：Low-Viscosity Crustal Layer Controls the Crustal Architecture and Thermal Distribution at Hyperextended Margins: Modeling Insight and Application to the Northern South China Sea Margin

作者：Li, Fucheng[1];Sun, Zhen[1];Pang, Xiong[2];Liao, Jie[3];Yang, Hongfeng[4];Xie, Hui[5];Zhuo, Haiteng[1];Zhao, Zhongxian[1]

机构：[1]South China Sea Inst Oceanol, CAS Key Lab Ocean & Marginal Sea Geol, Guangzhou, Guangdong, Peoples R China;[2]China Natl Offshore Oil Corp Ltd Deepwater, China Natl Offshore Oil Corp Ltd Shenzhen, Shenzhen, Peoples R China;[3]Sun Yat Sen Univ, Sch Earth Sci & Engn, Guangzhou, Guangdong, Peoples R China;[4]Chinese Univ Hong Kong, Earth Syst Sci Programme, Fac Sci, Hong Kong, Peoples R China;[5]Guangdong Ocean Univ, Guangdong Prov Key Lab Coastal Ocean Variat & Dis, Zhanjiang, Peoples R China

年份：2019

卷号：20

期号：7

起止页码：3248

外文期刊名：GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS

收录：SCI-EXPANDED(收录号：WOS:000480282600009)、、EI(收录号：20192807178000)、Scopus(收录号：2-s2.0-85068717289)、WOS

基金：We thank Yang Yu from the Guangzhou Institute of Geochemistry, CAS, for leading a fruitful field trip in South China. The China National Offshore Oil Corporation is also much appreciated for providing the reflection seismic profile. Jiangyang Zhang and Ning Qiu are appreciated for the discussion on gravity modeling. The authors also would like to show great gratitude to Laetitia Le Pourhiet, an anonymous reviewer, and Editor Thorsten Becker for their constructive suggestions and comments on the manuscript. This work is supported by the Guangdong NSF research team project (2017A030312002), the K. C. Wong Education Foundation (GJTD-2018-13), the National Natural Science Foundation of China (41606073, 41576070, and 41606065), the Strategic Priority Research Program of the Chinese Academy of Science (XDA13010303), the Guangdong Natural Science Foundation of China (No. 2016A030310331), the OMG Visiting Fellowship (OMG18-15), and the National Science and Technology Major Project of the Ministry of Science and Technology of China (2016ZX05026-003). Hongfeng Yang thanks Faculty of Science, CUHK. The numerical raw data that are used to visualize in this manuscript are available at https://pan.baidu.com/s/1oblDgO8xwLjgZFXX9yDglg by entering the extraction code "xkmv." The heat flow and gravity data have been published before in several publications indicated in the text. The reflection seismic profile used in this study is proprietary data from the CNOOC, which is JPG format file and has been presented in Figure 11.

语种：英文

外文关键词：low-viscosity crustal layer; rifted margin; hyperextended crust; high heat flow; South China Sea margin

外文摘要：A low-viscosity crustal layer (LVCL) due to partial melt and/or hydration has been detected within the continental crust (e.g., in South China block), but its role in the development of hyperextended margins is still not entirely understood. Using 2-D thermomechanical modeling, we simulate the lithospheric extension with a LVCL embedded within the continental crust. Results show that the ductile layer determines the width of highly thinned crust and the crustal thermal distribution. Detailed effects are found by varying the initial effective viscosity and thickness of the layer: (1) a rheologically weaker and/or thicker LVCL accommodates more deformation and thus results in a slow and distributed crustal thinning and (2) preferential removal of the lithospheric mantle places the crust in direct contact with the hot upwelling asthenosphere, promoting the development of highly thinned and hot continental crust. Both the widths of highly thinned crust and the thermal values increase when the rheology of the ductile layer decreases or the thickness increases. Furthermore, we obtain the crustal thickness and geothermal characteristics of the northern South China Sea (SCS) margin using reprocessed geophysical data and newly complied heat flow data. A detailed comparison of our modeling results with the northern SCS margin suggests that variation in the LVCL thickness may be a possible mechanism for the differential width of highly thinned crust and high heat flow zone along strike of the northern SCS margin.