使用河北省测震台网7个宽频带地震台记录,采用CAP方法反演2006年7月4日文安MW5.1地震震源机制解,并结合区域地质背景讨论发震构造。结果显示,文安5.1级地震的最佳双力偶解为:节面Ⅰ走向215°,倾角87°,滑动角-115°;节面Ⅱ走向118°,倾角25°,滑动角-8°,震源深度为15 km,联合地质构造确定地震断层面为隐伏的NE向断裂带,为正断层兼走滑断层,与其他研究结果基本一致。
Based on the records of 7 stations in Hebei seismic network, we inverted the focal mechanism of Wen'an MW5.1 earthquake on July 4 2006 with the "Cut and Paste"(CAP) method, and analyzed the seismogenic structure combining with the geological background. Our result shows that the best double couple solution of the MW 5.1 earthquake is 215°, 87 ° and -115 ° for strike, dip and rake angles, respectively. Another nodal plane solution is 118°, 25 ° and -8 °. The geologic structure shows that the seismic fault in the north east concealed fault, properties with fault and strike-slip faults. This result is consistent with other research findings.
2017,38(2): 17-21 收稿日期:2016-06-17
DOI:10.3969/j.issn.1003-3246.2017.02.004
基金项目:河北省地震局地震科技星火计划项目(项目编号:DZ2014122507)
作者简介:张小涛(1978-),男,主要从事地震学与电磁学研究工作。E-mail:zxt.12@163.com
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