宜宾乡镇级密集地震监测台网建设及地震信号分析

Dense Earthquake Monitoring Network in Town and Township of Yibin and Analysis of Earthquake Signals

在宜宾建设地震监测台网,布置在地震多发区域的八个台站形成乡镇级密集地震监测台网。与传统强震台阵不同,各台站均包含地面测点和邻近多层学校建筑楼层测点。共获取136次地震诱发的地面及楼层信号共约2000条,根据信号特点大致分为震中区、近区、远区和超远区四类信号。震中区和近区信号数据量最多,为强地面和楼层加速度数据,其中震中距小于10 km的震中区信号地面及建筑楼层信号共56条。选取了代表性的数据,分析了地面平均反应谱特征,给出了地面加速度峰值随震中距的衰减曲线。还对地面和/或楼层信号峰值相对较小的超远区信号、远区信号作了讨论。

Earthquake monitoring networks has been established in Yibin area.A dense earthquake monitoring network for town and township is formed by eight monitoring stations in the rural region prone to seismic activity.Different from traditional strong-motion arrays,each station contains ground point and floor point of adjacent school buildings.A total of 2000 records of ground and floor acceleration signals induced by 136 earthquakes were obtained,categorized into four types based on signal characteristics:epicenter zone,near zone,far zone,and very far zone signals.The data from the epicenter and near zone signals are valuable strong ground and floor acceleration signals and of large amount,with 56 records of ground and floor signals in region with epicenter distance less than 10 km.This paper selects representative data to analyze the characteristics of ground average response spectrum.The typical attenuation curve of peak ground acceleration with respect to epicenter distance is given.The very far zone and far zone signals with relatively lower peak values of ground and/or floor acceleration are also discussed.