吉林松原MS5.7、MS5.1地震强震动记录特征分析*

(1.甘肃兰州地球物理国家野外科学观测研究站,甘肃 兰州 730000; 2.吉林省地震局,吉林 长春 130000)

松原地震; 强震动记录; 反应谱; 衰减关系; 强震动观测

The Characteristics of Strong Motion Records of the Songyuan MS5.7 and MS5.1 Earthquakes,Jilin Province
XU Qin1,CHEN Linrong2,ZHANG Yu2,WANG Wencai1,SHI Wenbing1

(1. Lanzhou National Geophysical Observation and Research Station,Lanzhou 730000,Gansu,China)(2. Jilin Earthquake Agency,Changchun1 30022,Jilin,China)

Songyuan earthquake; strong motion records; acceleration response spectrum; attenuation relationships; strong motion observation

备注

2018年5月28日和2019年5月18日在吉林省松原市先后发生MS5.7和MS5.1地震,对吉林省和黑龙江省强震动台网收集的24组地表强震动记录进行整理、基线校正和滤波等常规处理,分析2次地震记录的幅值、加速度反应谱特征,结果表明:①2次地震记录多为中远场(100 km以外),近场记录较少; ②MS5.7地震事件中获得的强震动记录PGA范围为2.25~192.30 gal,MS5.1地震事件中获得的强震动记录PGA范围为1.08~176.92 gal,最大PGA均由风华台获取; ③将PGA观测值与第五代《中国地震动参数区划图》(中强地震区)地震动衰减关系进行了对比发现垂直向和预测值吻合度较高; ④比较获取记录仪器烈度和地震调查烈度,达里巴台与调查烈度值完全吻合; 最后对典型台站2次地震反应谱和设计谱进行了分析发现,MS5.7长周期分量大于MS5.1; ⑤同一台站不同震级反应谱形状接近,且高频优于低频。

On May 28,2018 and May 18,2019,two MS5.7 and MS5.1 earthquakes occurred successively in Ningjiang district,Songyuan city,Jilin province.The 24 groups of strong ground motion records collected by the strong motion networks in Jilin province and Heilongjiang province were routinely processed,including classification,baseline correction and filtering.The amplitude and acceleration response spectrum characteristics of the two seismic records were analyzed.Most of the two seismic records were from the far and medium field(100km away),while few were from the near field.The MS5.7 PGA ranges from 2.25 to 192.30 gal,the MS5.1 PGA ranges from 1.08 to 176.92 gal,and the maximum PGA value was obtained by 22FHT.The observed PGA values were compared with the attenuation relationship of the fifth generation seismic zoning map(medium and strong seismic zones)in China,and the vertical direction(UD)was consistent with the predicted values.The instrumental intensity obtained was compared with the seismic investigation intensity,and the 22DLB station was completely consistent with the investigation intensity value.Finally,the response spectrum and design spectrum of two typical stations are analyzed,among which the long-period component of the MS5.7 event is larger than that of the MS5.1 event.The response spectra of different magnitudes of the same station are similar in morphology,and the high frequency response is better than the low frequency response.