Seismic anisotropy surrounding South China Sea and its geodynamic implications
Seismic anisotropy surrounding South China Sea and its geodynamic implications
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南海周边地震各向异性及其地球动力学意义
DOI：
10.1007/s11001-013-9194-4
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发表时间：
2013-09
期刊：
影响因子：
--
通讯作者：
杨挺
中科院分区：
文献类型：
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作者：
杨挺
关于南海的开放，已经提出了几种机制。在这里，我们使用SKS分裂分析来研究中国南海周围的地幔流。我们总共使用了23个地震台站和87个事件。我们应用频谱分析和聚类分析，找到一个稳定的分裂解决方案，为每个事件。主要结论如下：（1）在越南北方，NW-SE方向的快速运动与绝对板块运动平行，与分裂时间大于1 s的GPS观测结果平行，表明岩石圈和地幔是耦合的。相反，在越南南部，NE-SW快速方向表明岩石圈和软流圈是解耦的。(2)华南块体和台湾中部的快速方向分别为NE-SW和NS，均平行于地表形变，分裂时间均大于1 s，表明地幔流动与地表形变有关。(3)海南岛下观测到的NW-SE快速方向反映了印度-欧亚大陆的碰撞，并没有显示海南岛正下方的上涌地幔柱的迹象。这意味着海南岛与红河断裂的构造密切相关，而不是与华南地块的构造密切相关。(4)在婆罗洲，观测到的东北-西南方向平行于巴拉望海沟，与不活跃的原南海俯冲系统相关的流动一致。围绕南海的SKS分裂观测结果不能用单一的地质过程来解释，碰撞驱动挤出模型或板片拉伸模型都适合这里提供的数据。
Several mechanisms have been proposed for the opening of the South China Sea. Here, we use SKS splitting analysis to investigate the mantle flow surrounding the South China Sea. We use a total of 23 seismic stations and 87 events. We applied spectral analysis and cluster analysis to find a stable splitting solution for each event. The main conclusions are: (1) In northern Vietnam, the NW–SE fast direction is parallel to the absolute plate motion as well as GPS observations with splitting times larger than 1 s, indicating a coupled lithosphere and mantle. In contrast, in southern Vietnam, the NE–SW fast direction suggests that the lithosphere and asthenosphere are decoupled. (2) The fast directions beneath the South China Block and central Taiwan are NE–SW and NS respectively, both parallel to surface deformations with splitting times greater than 1 s, indicating that mantle flow and surface deformation are related. (3) The observed NW–SE fast directions beneath Hainan Island reflect the India–Eurasia collision, and show no signatures of an upwelling mantle plume directly underneath Hainan Island. This implies that Hainan Island is tectonically closely related to the Red River Fault, not the South China Block. (4) In Borneo, the observed NE-SW direction is parallel to the Palawan Trench, consistent with flow associated with the inactive proto-South China Sea subduction system. The SKS splitting observations surrounding South China Sea cannot be explained by a single geologic process, with either the collision-driven extrusion model or the slab pull model fitting the data presented here.
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DOI：
10.1201/9781420057492.ch10
发表时间：
2001-12
期刊：
--
影响因子：
--
作者：
B. Everitt
通讯作者：
B. Everitt
影响因子：
2.9
作者：
A. Miyashiro
通讯作者：
A. Miyashiro
影响因子：
5.8
作者：
R. Larson
通讯作者：
R. Larson
影响因子：
2.8
作者：
P. Silver;M. Savage
通讯作者：
P. Silver;M. Savage
影响因子：
--
作者：
S. Lebedev;G. Nolet
通讯作者：
S. Lebedev;G. Nolet