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针对云南景谷地震序列的特征研究尚浅.为讨论2014年10月7日云南景谷Ms6.6地震的发震构造及序列分布,利用云南测震台网提供的波形数据及观测报告,采用MSDP软件中的Loc3dSB(川滇)模型对主震进行了精确定位,然后利用双差定位法对2014年10月7日至31日期间的余震序列进行了重新定位;并使用P波初动与振幅比联合反演方法计算了震源机制解.结果显示:序列以走滑型地震为主,主压应力具有北北东及北东两个优势方向,序列分布呈北西向线性展布,主体分布在西北端较浅而东南端较深的线性区域内,说明地震的初始破裂面可能为北西向节面,为一次右旋走滑地震;余震分布还具有清晰的端点及转换区域,存在显著的分段差异.另外,东南端的余震在晚期逐渐转移到几何形态明显不同的段落上,近期地震危险性值得关注.
In order to discuss the seismogenic structure and sequence distribution of the Jinggu Ms6.6 earthquake in Yunnan Province on October 7, 2014, the waveform data and observation reports provided by Yunnan Seismograph Station are used to discuss the characteristics of the earthquake sequence in Yunnan Valley. MSDP software The Loc3dSB (Chuan-Dian) model was used to locate the main shock accurately. Then the double-difference method was used to reposition the aftershock sequence from October 7 to October 31, 2014. P-wave initial and amplitude ratios The joint inversion method is used to calculate focal mechanism solutions. The results show that the sequence is dominated by a strike-slip type of earthquake, and the principal compressive stress has two predominant orientations, north and east, and northeast. The sequence distribution shows a NW distribution linearly with the main distribution in the northwest It is shown that the initial rupture plane of the earthquake may be a NW strike plane and a right-lateral strike-slip earthquake. The aftershock distribution also has a clear endpoint and transition region with significant subdivision In addition, aftershocks at the southeast end gradually migrated to segments with significantly different geometries in the late period, and the recent earthquake risk deserves attention.