Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume

doi:10.1007/s11430-021-9894-7

CORC > 深海科学与工程研究所 > 中国科学院深海科学与工程研究所 > 深海科学研究部 > 深海地球物理与资源研究室

	Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume
	Xia, Shaohong 2,3; Fan, Chaoyan 2,3; Wang, Dawei 1; Cao, Jinghe 3; Zhao, Fang 3
刊名	SCIENCE CHINA-EARTH SCIENCES
	2022-03-10
页码	18
关键词	Crustal structure Hyperextension Magmatism Hainan mantle plume Qiongdongnan Basin
ISSN号	1674-7313
DOI	10.1007/s11430-021-9894-7
通讯作者	Xia, Shaohong
英文摘要	The Qiongdongnan Basin (QDNB) is a rift basin located in the extension direction of the oceanic ridge of the Northwest Subbasin of the South China Sea. This basin is surrounded by Late Cenozoic Ocean Island Basalts (OIBs) magmatism associated with the putative Hainan mantle plume. However, how the Hainan mantle plume has affected the QDNB has not been studied in detail. To reveal the crustal structure of the QDNB and the possible influence of the Hainan mantle plume, we conducted a wide-angle seismic exploration from Hainan Island across the QDNB to the Xisha Block, and obtained the crustal structure by travel-time tomography. The results show that the crustal stretching factors of the Northern and Southern Rises of the QDNB are estimated to be 1.3-2.0, indicating slight or moderate crustal thinning. Whereas, the crustal stretching factor in the Central Depression of the QDNB is estimated to be more than 3.0, which means that the crust has been hyperextended. Controlled by two detachment faults (F2 and F11), the upper and lower crust show brittle and ductile thinning, respectively. Three anomalous low-velocity conduits penetrating the crystalline crust are developed in the Songnan Uplift and the Southern Rise of the QDNB. Their P-wave velocities are 5.5-6.0 km s(-1), which are significantly lower than those of the surrounding crust (6.0-6.8 km s(-1)). The Late Cenozoic magmatic intrusions (e.g., sills and dikes) and hydrothermal activities can be observed in the sedimentary strata above these low-velocity conduits. We interpret that the low-velocity conduits might be the crustal magmatic footprints of the Hainan mantle plume, due to the correlated distributions of OIB-type magmatism, the magmatic intrusion patterns, the deep structure of the Hainan mantle plume and the high heat flow of 95 mW m(-2). Thus, we propose that the crustal structure of the QDNB is the product of crustal hyperextension in the rifting stage and subsequently affected by the Hainan mantle plume magmatism. This study provides a typical case for understanding the influence of a mantle plume on the continental crust with pre-existing rift structures.
资助项目	National Natural Science Foundation of China[42076071] ; National Natural Science Foundation of China[42006071] ; National Natural Science Foundation of China[41576041] ; Key Research and Development Plan of Hainan Province[ZDYF2020198] ; Rising Star Foundation of the South China Sea Institute of Oceanology[NHXX2017DZ0101] ; Rising Star Foundation of the South China Sea Institute of Oceanology[NHXX2019DZ0201] ; Special Research Assistant Project of Chinese Academy of Sciences
WOS关键词	SOUTH CHINA SEA ; NORTHERN CONTINENTAL-MARGIN ; SEISMIC VELOCITY STRUCTURE ; LATE CENOZOIC BASALTS ; NORTHWESTERN MARGIN ; POSTRIFT MAGMATISM ; OCEANIC-CRUST ; XISHA TROUGH ; FLUID-FLOW ; BENEATH
WOS研究方向	Geology
语种	英语
出版者	SCIENCE PRESS
WOS记录号	WOS:000769377800001
资助机构	National Natural Science Foundation of China ; Key Research and Development Plan of Hainan Province ; Rising Star Foundation of the South China Sea Institute of Oceanology ; Special Research Assistant Project of Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://ir.idsse.ac.cn/handle/183446/9256]
专题	深海科学研究部_深海地球物理与资源研究室
通讯作者	Xia, Shaohong
作者单位	1.Chinese Acad Sci, Inst Deep Sea Sci & Engn, Sanya 572000, Peoples R China 2.SCSIO, Sanya Inst Oceanol, Sanya 572100, Peoples R China 3.Chinese Acad Sci, South China Sea Inst Oceanol, Key Lab Ocean & Marginal Sea Geol, Guangzhou 510301, Peoples R China
推荐引用方式 GB/T 7714	Xia, Shaohong,Fan, Chaoyan,Wang, Dawei,et al. Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume[J]. SCIENCE CHINA-EARTH SCIENCES,2022:18.
APA	Xia, Shaohong,Fan, Chaoyan,Wang, Dawei,Cao, Jinghe,&Zhao, Fang.(2022).Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume.SCIENCE CHINA-EARTH SCIENCES,18.
MLA	Xia, Shaohong,et al."Hyperextended crustal structure of the Qiongdongnan Basin and subsequent magmatic influence from the Hainan mantle plume".SCIENCE CHINA-EARTH SCIENCES (2022):18.