Previous Articles     Next Articles

Research on Focal Mechanism Solutions of Wenchuan Earthquake Sequence

CUI Xiaofeng1, HU Xingping1, YU Chunquan2, TAO Kai2, WANG Yanhua1, NING Jieyuan2   

  1. 1. Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085; 2. School of Earth and Space Sciences, Peking University, Beijing 100871;
  • Received:2010-12-21 Online:2011-11-20 Published:2011-11-20



  1. 1. 中国地震局地壳应力研究所, 北京 100085; 2. 北京大学地球与空间科学学院, 北京 100871;

Abstract: Based on the initial P wave polarity of digital wave form data given by Chinese National Seismic Network, regional seismic network, temporary seismic networks as well as some IRIS stations, employing the improved grid point test method, 121 reliable focal mechanism solutions of Wenchuan earthquake sequence (M 4.0) are determined. The results show that the initial rupture of mainshock is purely thrust. The aftershocks of Wenchuan earthquake sequence are mostly thrust or strike-slip, and there is a characteristic of subsection distribution. The P axes shows a dominant distribution in the directions of NWW-SEE and NEE-SWW.

Key words: Wenchuan earthquake sequence, initial P wave polarity, focal mechanism solution

摘要: 利用2008年5月12日至8月7日包括国家地震台网、 地方区域地震台网和流动地震台网在内的1023个地震台站及IRIS台站的数字地震波形记录资料, 读取P波初动极性, 并采用改进的格点尝试法对汶川地震序列震源机制解进行求解, 给出121个4.0级以上质量可靠的震源机制解。根据求解结果发现: 汶川Ms 8.0级主震P波初动解为纯逆冲型; 汶川余震序列震源机制解绝大部分是逆冲型或走滑型地震, 并具有分段分布特征; 其P轴方位有两个优势分布方向: 北西西?南东东向和北东东?南西西向。

关键词: 汶川地震序列, P波初动, 震源机制解

CLC Number: