2020年1月19日新疆伽师M_S 6.4地震总结

系统总结2020年1月19日新疆伽师M_S6.4地震发生前出现的地震活动和地球物理观测等异常，结果如下：(1)地震活动：震前存在地震平静、高频、带状分布等中期和短期异常；(2)地球物理观测：震中300 km范围内存在水位、水温、基岩温度、断层氢、地倾斜、重力、地磁等测项，其中7个异常测项均为趋势异常，短临变化特征不突出；(3)综合方法主要为年尺度趋势异常。梳理并总结此次地震序列的动态跟踪过程，发现：该地震序列主要分布在柯坪塔格推覆构造附近，主震震源机制为逆冲型破裂为主，余震丰富，序列b值、h值于震后15天左右逐渐趋于稳定。综合分析认为，在伽师M_S6.4地震发生前，地震活动异常具有中期逐渐向短期逼近的过程，以趋势类为主的地球物理观测，震前未出现或未发现具有短期意义的异常，而是主要提供了后续强震的发生地点和震级的判定依据。

About Jiashi MS 6.4 earthquake in Xinjiang on Jan. 19, 2020

Systematically summarized the observed seismicity and geophysical anomalies before Jiashi M_S 6.4 earthquake in Xinjiang Uygur Autonomous Region on January 19, 2020. In terms of seismicity, some medium-term and short-term anomalies such as seismic quiescence, high seismic frequency, and belt-like seismic distribution emerged before the occurrence of Jiashi earthquake. In terms of geophysical observations, measurements such as water level, water temperature, bedrock temperature, fault hydrogen, earth tilt, gravity, geomagnetism, etc. are available within 300 km of the epicenter of the Jiashi earthquake and all of the 7 measurements which show abnormal before the mainshock are long-term anomalies, and short-term information is not obvious before the Jiashi earthquake. The anomalies identified by the comprehensive method are one-year-term. The dynamic tracking process of the Jiashi M_S 6.4 earthquake sequence is analyzed and summarized. The Jiashi earthquake sequence is mainly distributed in the vicinity of Kalpintag tectonic, the mainshock source mechanism is thrust fracture and the aftershocks of the sequence are abundant. The b value and h value of the sequence gradually tend to be stable around 15 days after the occurrence of the mainshock. In summary, the process that seismic anomalies are changing gradually from long-term to short-term before Jiashi M_S 6.4 earthquake can be observed, and short-term geophysical anomalies are not emerged or not found before the earthquake. The long-term anomalies found before the Jiashi earthquake mainly provided the location and magnitude information of the imminent event.