Shear wave velocity structure of Reed Bank, southern continental margin of the South China Sea
Shear wave velocity structure of Reed Bank, southern continental margin of the South China Sea
复制标题
南海南部大陆边缘芦滩剪切波速度结构
DOI：
10.1016/j.tecto.2015.01.006
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发表时间：
2015-03
期刊：
影响因子：
2.9
通讯作者：
Niu, Xiongwei
中科院分区：
文献类型：
--
作者：
Zhao, Minghui;Qiu, Xuelin;Wu, Zhenli;Niu, Xiongwei
在前人p波模型的基础上，采用二维射线追踪方法模拟了南海南部大陆边缘礼乐滩广角地震剖面（OBS973-2）横波速度结构。该剖面长369公里，由15个三分量海底地震仪（OBS）组成。主要结果如下：(1)模型由7层组成，剪切波速从沉积层顶部的0.7 km/s增加到地壳下部的4.0 km/s。(2)莫霍线深度由礼乐滩的20 ~ 22 km减小到大洋盆地的9 ~ 11 km，莫霍线以下横波速度为4.2 km/s。(3) vp /Vs随沉积层深度的增加而减小，这是由于岩石压实和固结的增加。(4)大陆上地壳（模式距离90 ~ 170 km） s波速度相对较低（2.5 ~ 3.2 km/s）， vp /Vs比值相对较高（1.75 ~ 1.82），与前人p波模式中p波速度较低和MCS数据显示的正断层相对应，表明Reed Bank地区南海形成过程中发生了强烈的区域伸展运动。(5) s波构造表明芦苇滩地壳的岩石组成与北缘东段不同，否定了芦苇滩与东沙群岛的共轭关系。根据p波模型和其他数据，我们推断Reed Bank和Macclesfield是在裂陷和破碎过程中从同一大陆地壳分离出来的。
The shear wave velocity structure of a wide angle seismic profile (OBS973-2) across Reed Bank in the southern continental margin of the South China Sea (SCS) is simulated by 2-D ray-tracing method, based on its previous P-wave model. This profile is 369-km-long and consists of fifteen three-component ocean bottom seismometers (OBS). The main results are as follows.(1) The model consists of seven layers and the shear wave velocity increases from 0.7 km/s at the top of sediment layer to 4.0 km/s in the lower crust. (2) The Moho depth decreases from 20-22 km at the Reed Bank to 9-11 km at the deep oceanic basin with the shear wave velocity of 4.2 km/s below the Moho. (3) TheVp/Vs ratio decreases with depth through the sedimentary layers, attributed to increased compaction and consolidation of the rocks. (4) In the continental upper crust (at model distance 90-170 km), S-wave velocity (2.5–3.2 km/s) is relatively low andVp/Vs ratio (1.75–1.82) is relatively high compared with the other parts of the crust, corresponding to the lower P-wave velocity in the previous P-wave model and normal faults revealed by MCS data, indicating that a strong regional extensional movement had occurred during the formation process of the SCS at the Reed Bank area. (5) The S-wave structures indicate that Reed Bank crust has different rock compositions from that in the east section of the northern margin, denying the presence of conjugate relationship of Reed Bank with Dongsha islands. According to P-wave models and other data, we inferred that Reed Bank and Macclesfield were separated from the same continental crust during the rifting and break-up process.
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影响因子：
2.9
作者：
Y. Pin;Z. Di;Zhao-shu Liu
通讯作者：
Y. Pin;Z. Di;Zhao-shu Liu
DOI：
10.1007/s11430-011-4324-9
发表时间：
2011
期刊：
Science China Earth Sciences
影响因子：
--
作者：
Zhenli Wu;Jiabiao Li;A. Ruan;Hai Lou;W. Ding;X. Niu;Xibing Li
通讯作者：
Zhenli Wu;Jiabiao Li;A. Ruan;Hai Lou;W. Ding;X. Niu;Xibing Li
影响因子：
3.5
作者：
Ke Ru;J. Pigott
通讯作者：
Ke Ru;J. Pigott
影响因子：
2.9
作者：
P. Digranes;R. Mjelde;S. Kodaira;H. Shimamura;T. Kanazawa;H. Shiobara;E. Berg
通讯作者：
P. Digranes;R. Mjelde;S. Kodaira;H. Shimamura;T. Kanazawa;H. Shiobara;E. Berg
影响因子：
4.2
作者：
H. Kudrass;M. Wiedicke;P. Čepek;H. Kreuzer;P. Müller
通讯作者：
H. Kudrass;M. Wiedicke;P. Čepek;H. Kreuzer;P. Müller