永宁2次M_S4.5地震震源机制及深度
发布时间：2018-09-08 08:30
【摘要】：2010年6月22日和2012年11月20日在宁夏回族自治区银川市永宁县发生了2次M_s4.5地震,在银川市及周边地区引起了强烈震感。为了更好地认识这2次地震的发震构造,利用宁夏及邻近几个省份区域台网的近震波形资料,首先通过HyP2000绝对定位得到震中位置及余震震中分布;然后使用TDMT矩张量方法反演了震源机制解与震源深度。结果显示:2010年6月22日地震节面Ⅰ走向208°,倾角89°,滑动角-164°,节面Ⅱ走向117°,倾角74°,滑动角-2°;2012年11月20日地震节面Ⅰ走向284°,倾角79°,滑动角12°,节面Ⅱ走向192°,倾角78°,滑动角169°。综合Snoke法,得出这2次地震主控断层均为走向NNE、倾向NWW的右旋走滑断层;前者带有少量的拉张分量,后者带有少量逆冲分量,矩震级分别为M_w4.5和M_w4.3。根据HyP2000精定位、TDMT矩张量拟合误差和sPn深度震相等3种方法确定最佳震源深度分别为22km和8km,均属浅源地震。从定位震中和震源机制解来看,虽然2次地震震中仅差13km,但前者震源比后者深,分析其原因,可能为2012年11月20日地震由银川断裂的主断裂控制,而2010年6月22日地震由银川断裂的南支分断裂控制。
[Abstract]:Two M_s4.5 earthquakes occurred in Yongning County of Yinchuan City of Ningxia Hui Autonomous region on June 22, 2010 and November 20, 2012, which caused strong tremors in and around Yinchuan City. In order to better understand the seismogenic structure of the two earthquakes, the epicenter location and epicenter distribution of aftershocks are obtained by using the near seismic waveform data of the regional seismic network in Ningxia and several neighboring provinces. Then the focal mechanism solution and focal depth are inversed by TDMT moment Zhang Liang method. The results show that the seismic nodes I strike 208 掳, dip angle 89 掳, slip angle -164 掳, node 鈪，
本文编号：2229980
[Abstract]:Two M_s4.5 earthquakes occurred in Yongning County of Yinchuan City of Ningxia Hui Autonomous region on June 22, 2010 and November 20, 2012, which caused strong tremors in and around Yinchuan City. In order to better understand the seismogenic structure of the two earthquakes, the epicenter location and epicenter distribution of aftershocks are obtained by using the near seismic waveform data of the regional seismic network in Ningxia and several neighboring provinces. Then the focal mechanism solution and focal depth are inversed by TDMT moment Zhang Liang method. The results show that the seismic nodes I strike 208 掳, dip angle 89 掳, slip angle -164 掳, node 鈪，
本文编号：2229980
本文链接：https://www.wllwen.com/kejilunwen/diqiudizhi/2229980.html
