2018年9月伽师地区发生震群事件,连续发生18次M > 3.0地震,最大震级M 5.5,获取大量强震动记录,初步分析此次震群强震动记录特征、记录峰值比、场地地震反应,结果发现:加速度记录峰值在震中距30 km范围内衰减较快,震中距30-100 km范围内衰减平缓;强震动加速度记录峰值水平向与垂直向比值为1-3,均值约1.5;场地共振频率为0.48-1.56 Hz,平均放大倍数为8.4-9.5。
Earthquake swarm event occurred in Jiashi area in September 2018, occurred continuously 18 M > 3.0 earthquakes, with the maximum magnitude of M 5.5, a large number of strong motion records. The characteristics of strong motion records, peak value ratio and site seismic response were preliminary analyzed. The results show that the peak value of acceleration records decays rapidly in the range of 30 km around the epicenter and the attenuation is gentle in epicenter moment 30-100 km. The ratio of peak horizontal to vertical acceleration is 1-3, the average value is about 1.5, the site resonance frequency is 0.48-1.56, the average magnification is 8.4-9.5.
2019,40(6): 22-27 收稿日期:2019-05-24
DOI:10.3969/j.issn.1003-3246.2019.06.004
基金项目:新疆维吾尔自治区地震局对外协作项目(项目编号:300130201);新疆维吾尔自治区地震局青年科学基金(项目编号:201710)
作者简介:张振斌(1975-),男,主要从事强震动观测与研究工作。E-mail:zhang7806118@126.com
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