摘要
选用福建数字地震台网宽频带记录,利用CAP方法反演福建漳浦海域2016年6月18日ML4.0级地震震源机制解。反演得到震级M_W为3.7,节面Ⅰ走向85°、倾角82°、滑动角-167°;节面Ⅱ走向353°、倾角77°、滑动角-8°;最佳深度分布于11 km附近。分析认为此次地震的发震断层为走滑型断层,东西向节面为断层面,节面走向与震中附近的滨海断裂走向存在差异,滨海断裂是发震构造的可能性较小,漳浦海域地震可能是横向构造断层活动的结果。
Using the broadband records of Fujian Regional Seismic Network, the paper inverts the focal mechanisms of the M_L 4.0 earthquake in Zhangpu sea area on June 18 th, 2016 by CAP method. The results show that the best pair of couple solution is 85°, 82° and-167° for strike, dip and rake angles respectively; the strike, dip and rake angles of the other nodal plane are 353°, 77°and-8° respectively; the moment magnitude was MW3.7, and the optimum focal depth is on 11 km nearby. The results show that the earthquake mechanism was a strike-slip faulting. East-West nodal plane is the seismogenic fault. The both strikes of the two nodal plane are significantly different with the strike of the Binhai zone fault, the earthquake may not occur on the Binhai zone fault, the Zhangpu Sea earthquake may be the result of lateral tectonic faulting.
引文
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