2017年8月9日新疆博尔塔拉州精河县发生M_S6.6地震，震中44.3°N、82.9°E，震源深度11km，精河地震发生在库松木契克山前断裂附近，基于远震波形记录反演的震源机制为逆冲型，地质调查结果显示主震破裂未出露地表。利用地震精定位研究余震的空间分布，结果显示，余震展布与库松木契克山前断裂的走向基本吻合，且余震主要分布在主震西侧，单侧破裂特征明显，余震的深度集中在5～15km。基于M-t图分析序列的衰减特征发现，截至2017年8月20日，序列中M_L2.0、M_L3.0余震相对丰富，衰减基本正常。G-R关系给出的b值为0.54，外推最大余震震级为M_S5.6，h值为2.17，均显示该序列为主-余型。M_S≥4.0余震的等待时间与发生时间较好地满足双对数线性关系，同样为主-余型地震的特征。断层面上静态滑动量分布相对单一且集中，最大滑动位于沿倾向10km处附近，与地质调查主震断层未出露地表的结果一致，同时也表明主震破裂较充分。基于数字波形资料计算出的余震视应力与震级间很好地符合指数关系，扣除震级变化影响后的序列视应力未出现显著高值，也表明此次破裂的能量释放比较充分。

On August 9, 2017, the earthquake with M_S6.6 occurred in Jinghe County, Xinjiang, China, with epicenter at 44.3°N, 82.9°E. Its focal depth was 11km. The Jinghe M_S6.6 earthquake occurred near Kusongmuqike piedmont fault. Its focal mechanism inversed from teleseismic waveforms is reverse faulting. Geological investigation shows that the rupture in the earthquake didn't reach to the earth surface. According to the results of high-resolution event relocation, the aftershocks distribute nearly along the strike of the Kusongmuqike piedmont fault. As most of the aftershocks locate in the west of the mainshock, the rupture is likely to propagate in single direction. The focal depths of the aftershocks concentrate between 5km to 15km. In order to study the feature of the earthquake sequence, we graph their magnitudes against time up to August 20, 2017. The earthquakes with M_L2.0 and M_L3.0 are abundant and the sequence attenuates near regularly. The b-value from the G-R law is 0.54, and the extrapolated maximum aftershock magnitude is M_S5.6. The h-value from Omori's law is 2.17. The relation between the ‘wait time’ of an aftershock with magnitude over M_S4.0 and its ‘occurrence time’ is studied. We find the logarithmic of the ‘wait time’ is linear with the logarithmic of the ‘occurrence time’. So the Jinghe earthquake sequence should be a mainshock-aftershock type. Inversion from the teleseismic data shows that slips distribute simply on the fault. The maximum slip concentrates on 10km along the dip. This result is consistent with the geological investigation which proposed the rupture didn't extend to the earth surface. The fault slips also indicate that the rupture in the mainshock is sufficient. Apparent stress of aftershocks calculated from digital waveforms increases exponentially with magnitude. Relative apparent stress which removed the change with magnitude doesn't have significantly high value. That also indicates energy was released sufficiently in the rupture process.

P315

川滇国家地震监测预报实验场项目（2016CESE0101）、国家自然科学基金（41504047、41404045）共同资助