Using an empirical Green’s function (EGF) approach and data from local to regional distances we analyzed rupture propagation directivity in the three mainshocks (ML 6.0–6.1) and in six of the largest aftershocks (ML 5.0 – 5.5) of the 2017 Kerman, Iran, seismic sequence. The EGF procedure was based on data from smaller events (ML 4.0 – 4.8). Deconvolution was applied separately to P and S phases. Using the P-wave data, we calculated relative source-time functions and examined azimuthal variations in rupture duration. In the S-wave analysis, we investigated along strike rupture directivity of the mainshocks and the largest aftershocks by evaluating azimuthal variation of the amplitude spectra. Two of the mainshocks and four of the aftershocks clearly showed rupture propagation from the south-east toward the north-west. The third mainshock and one of the aftershocks suggested almost bilateral rupture propagation, and one aftershock showed rupture directivity to the southeast. It seems that the rupture propagation direction in the area is generally to the north-west and the events which have different propagation directions are located within the NW and SE ends of the faulting area. We suggest that the general rupture propagation direction in the area is steered by regional tectonic stress field regarding the faulting orientations which have been affected by stress redistribution around a restraining bend.

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伊朗东部2017年12月克尔曼地震的方向性分析

使用经验格林函数（EGF）方法和从本地到区域距离的数据，我们分析了伊朗2017年克尔曼的三个主震（ML 6.0–6.1）和六个最大余震（ML 5.0 – 5.5）中的破裂传播方向性。 ，地震序列。EGF程序基于较小事件的数据（ML 4.0 – 4.8）。去卷积分别应用于P和S相。利用P波数据，我们计算了相对震源时间函数，并研究了破裂持续时间的方位角变化。在S波分析中，我们通过评估振幅谱的方位角变化，研究了主震和最大余震的破裂走向。两个主震和四个余震清楚地表明，破裂是从东南向西北传播的。第三次主震和余震之一表明几乎双侧破裂传播，而一次余震向东南方向显示破裂方向。似乎该区域的破裂传播方向通常是西北方向，传播方向不同的事件位于断层区域的西北端和东南端。我们认为，该区域的总体破裂传播方向受区域构造应力场控制，该区域受断裂弯折方向的断裂方向影响，该断裂方向受约束弯头周围应力重新分布的影响。似乎该地区的破裂传播方向一般是西北方向，传播方向不同的事件位于断层区域的西北端和东南端。我们认为，该区域的总体破裂传播方向受区域构造应力场控制，该区域受断裂弯折方向的断裂方向影响，该断裂方向受约束弯头周围应力重新分布的影响。似乎该区域的破裂传播方向通常是西北方向，传播方向不同的事件位于断层区域的西北端和东南端。我们认为，该区域的总体破裂传播方向受区域构造应力场控制，该区域受断裂弯折方向的断裂方向影响，该断裂方向受约束弯头周围应力重新分布的影响。