Thermal and rheological structures of the Xisha Trough, South China Sea
文献类型：期刊论文
| 作者 | Shi, XB ; Zhou, D ; Qiu, XL ; Zhang, YX |
| 刊名 | TECTONOPHYSICS
 |
| 出版日期 | 2002 |
| 卷号 | 351期号:4页码:285-300 |
| 关键词 | Xisha Trough failed rift gravity modeling thermal structure rheological structure |
| ISSN号 | 0040-1951 |
| 通讯作者 | xbshi@scsio.ac.cn |
| 中文摘要 | The Xisha Trough, located in the northwest of the South China Sea (SCS) mainly rifted 30 Ma ago, has been a failed rift since the cessation of the seafloor spreading of the NW subbasin. Based on the velocity-depth model along Profile OBH-4 across the Xisha Trough, a seven-layer density-depth model is used to estimate density structure for the profile. The relationship between seismic velocity and radiogenic heat production is used to estimate the vertical distribution of heat sources in the lower crust. The 2-D temperature field is calculated by applying a 2-D numerical solution of the heat conduction equation and the thermal lithosphere thickness is obtained from the basalt dry solidus (BDS). The rheology of the profile is estimated on the basis of frictional failure in the brittle regime and power-law steady-state creep in the ductile regime. Rheological model is constructed for a three-layer model involving a granitic upper crust, a quartz diorite lower crust and an olivine upper mantle. Gravity modeling supports basically the velocity-depth model. The Moho along Profile OBH-4 is of relatively high heat flow ranging from 46 to 60 mW/m(2) and the Moho beat flow is higher in the trough than on the flanks, The depth of the "thermal" lithospheric lower boundary is about 54 km in the center, deepens toward two sides, and is about 75 km at the northern slope area and about 70 kin at the southern Xisha-Zhongsha Block. Rheological calculation indicates that the two thinnest ductile layers in the crust and the thickest brittle layer in the uppermost mantle lie in the central region, showing that the Xisha Trough has been rheologically strengthened, which are mainly due to later thermal relaxation. In addition, the strengthening in rheology during rifting was not the main factor in hampering the breakup of the Xisha Trough. (C) 2002 Elsevier Science B.V. All rights reserved. |
| 学科主题 | Geochemistry & Geophysics |
| 收录类别 | SCI |
| 原文出处 | ELSEVIER SCIENCE BV |
| WOS记录号 | WOS:000177029800002 |
| 公开日期 | 2011-07-03 |
| 源URL | [http://ir.scsio.ac.cn/handle/344004/4716]  |
| 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 | Shi, XB,Zhou, D,Qiu, XL,et al. Thermal and rheological structures of the Xisha Trough, South China Sea[J]. TECTONOPHYSICS,2002,351(4):285-300. |
| APA | Shi, XB,Zhou, D,Qiu, XL,&Zhang, YX.(2002).Thermal and rheological structures of the Xisha Trough, South China Sea.TECTONOPHYSICS,351(4),285-300. |
| MLA | Shi, XB,et al."Thermal and rheological structures of the Xisha Trough, South China Sea".TECTONOPHYSICS 351.4(2002):285-300. |
入库方式： OAI收割
来源：南海海洋研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。