Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications

CORC > 南海海洋研究所 > 中国科学院南海海洋研究所 > 中科院边缘海地质重点实验室

	Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications
	Li, CF ; Shi, XB ; Zhou, ZY ; Li, JB ; Geng, JH ; Chen, B
刊名	GEOPHYSICAL JOURNAL INTERNATIONAL
	2010
卷号	182 期号:3 页码:1229-1247
关键词	Fourier analysis Inverse theory Magnetic anomalies: modelling and interpretation Marine magnetics and palaeomagnetics Heat flow Continental margins: divergent
ISSN号	0956-540X
通讯作者	cfl@tongji.edu.cn
中文摘要	P>The depths to the magnetic layer bottom (Z(b)) in the South China Sea (SCS) area are estimated by computing radially averaged amplitude spectra of total field magnetic anomalies. We test different sizes of moving windows in which the spectra are calculated to better understand how window sizes affect the depth estimations. Apart from lowering the resolutions of estimated Z(b), larger windows do not necessarily incur presumable increases in Z(b) in the SCS area. Although the centroid method is taken as our primary technique for estimating Z(b), for cross check, the spectral peak and the non-linear inversion methods are also applied to those windows where spectral peaks do appear. In a single window we may find discrepancy in Z(b) estimated from different techniques, but for all windows showing spectral peaks, the estimated Z(b) from one technique are grossly correlated with those from another. Our results show that most parts of the central SCS ocean basin and the northern continent-ocean transition (COT) zone have significantly smaller Z(b) than the surrounding continental blocks. In the surrounding continental regions Z(b) are averaged at about 34 km, a depth close to the Moho depth. The average Z(b) is about 22 km in the central basin, but this value is much larger than the Moho depth, signifying that the uppermost 10 km or so of the mantle beneath the central basin is also magnetized. The strong faulting and recent magmatism within the COT zone can account for the small Z(b) near the northern continental margin. The estimated Z(b) are also found very correlative to surface heat flow. This observation verifies dominant contributions to surface heat flow from incoming mantle heat flow due to thermal conduction. The positive correlations observed among Z(b) from different techniques as well as the good correlation between surface heat flow and Z(b) support the reasoning that our estimated Z(b) are within an acceptable range of accuracy.
学科主题	Geochemistry & Geophysics
收录类别	SCI
原文出处	WILEY-BLACKWELL PUBLISHING, INC
WOS记录号	WOS:000280997700010
公开日期	2011-07-03
内容类型	期刊论文
源URL	[http://ir.scsio.ac.cn/handle/344004/4314]
专题	南海海洋研究所_中科院边缘海地质重点实验室
推荐引用方式 GB/T 7714	Li, CF,Shi, XB,Zhou, ZY,et al. Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications[J]. GEOPHYSICAL JOURNAL INTERNATIONAL,2010,182(3):1229-1247.
APA	Li, CF,Shi, XB,Zhou, ZY,Li, JB,Geng, JH,&Chen, B.(2010).Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications.GEOPHYSICAL JOURNAL INTERNATIONAL,182(3),1229-1247.
MLA	Li, CF,et al."Depths to the magnetic layer bottom in the South China Sea area and their tectonic implications".GEOPHYSICAL JOURNAL INTERNATIONAL 182.3(2010):1229-1247.