Oceanic mantle gravimetric response to the seafloor spreading of the Southwest Sub-basin, South China Sea
Oceanic mantle gravimetric response to the seafloor spreading of the Southwest Sub-basin, South China Sea
复制标题
大洋地幔重力对南海西南次盆地海底扩张的响应
DOI：
10.1002/gj.2799
复制
发表时间：
2016
影响因子：
1.8
通讯作者：
Qiu Xuelin
中科院分区：
文献类型：
--
作者：
Lü Chuanchuan;Hao Tianyao;Yao Yongjian;Xing Jian;Qiu Xuelin
剩余地幔重力异常是岩石圈深部地幔结构的直接响应。我们利用国际大洋钻探计划第349次考察、10条地震剖面的解释和南海西南次海盆（SWSB）的测深数据等丰富的地球物理证据，从最新更新的自由空间重力异常中获取RMA。通过应用地壳均衡挠曲分析方法反演地壳厚度，并与海底地震层析成像结果进行对比，确定研究区地壳的详细厚度，从而计算出西南南大洋盆地的RMA值。讨论了RMA的主要特征及其与古扩张模式的关系，并提出了熔体提取变化引起的岩石圈非对称变形的含义。根据南洋杉化石扩散中心南北两侧的不对称RMA，我们倾向于南海大洋岩石圈形成过程中熔体保留深度和提取速率的不对称变化。版权所有© 2016约翰威利父子有限公司.
The residual mantle gravity anomaly (RMA) is a straightforward response of the deep mantle structure of the lithosphere. We acquired RMA from newly updated free‐air gravity anomaly by incorporating abundant geophysical evidences, such as the International Ocean Drilling Program expedition 349, the interpretation of 10 seismic profiles and the bathymetric data in the Southwest Sub‐basin (SWSB) of the South China Sea. By inverting the crustal thickness by the application of the isostatic flexure analysis, comparing with ocean bottom seismic tomography result, then determining a detail crustal thickness of the study region, we calculated the RMA of the oceanic basin in the SWSB. The main features of the RMA and their relation to the palaeo‐spreading pattern are discussed, and the implications of the asymmetric lithospheric deformation due to variations in melt extraction are proposed. In the light of the asymmetric RMA at the north and south sides of the fossil spreading centre in the SWSB, we preferred asymmetric melt retention depth and extraction rate changes during the oceanic lithosphere creation of the South China Sea. Copyright © 2016 John Wiley & Sons, Ltd.