利用同址比测法估计在线地震仪灵敏度  

Calculation of the sensitivity of the in-situ seismograph using the collocation test

作　　者：许卫卫[1] 杨大克[1] 袁松湧[1] 马洁美[1] 谢剑波[2] 李小军[3] XU WeiWei;YANG DaKe;YUAN SongYong;MA JieMei;XIE JianBo;LI XiaoJun(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Earthquake Administration of Guangdong Province,Guangzhou 510070,China;Earthquake Administration ofHebei Province,Shijiazhuang 050021,China)

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]广东省地震局,广州510070 [3]河北省地震局,石家庄050021

出　　处：《地球物理学报》2021年第12期4572-4581,共10页Chinese Journal of Geophysics

基　　金：国家自然科学基金(42074050);国家重点研发计划(2017YFC1500201)联合资助.

摘　　要：地震仪灵敏度参数的精度直接决定了地动量记录恢复的准确度.在中国国家地震台网的四个台站布设了多套参考地震仪,分别用地震事件和地脉动噪声作为信号源,用相关分析方法计算了在线地震仪相对于参考地震仪的灵敏度.结果表明:地震事件和地脉动噪声在垂直、南北、东西三个分量均可稳定获取在线地震仪灵敏度的可靠估计,并且两种方法表现出良好的一致性.对于无法中断观测的在线地震仪而言,本文提出的利用地脉动噪声相关分析估计仪器灵敏度是一个有效方法.在测试的四个台站中,蒙城台和九江台两个台站部分分量灵敏度误差超过3%,其中蒙城台的垂直向和南北向误差将近10%.分析结果表明,对中国国家地震台网地震仪的灵敏度进行普查非常有必要,这项工作对提高我国地震台站的观测数据质量具有重要意义.The accuracy of ground motion restored from seismic records is directly determined by the accuracy of seismograph sensitivity.To further address this issue,we deployed multiple sets of reference seismographs at four Chinese National Digital Seismographic Network stations and estimated the relative sensitivities of the in-situ seismographs at these stations by the correlation technique using earthquake events and micro-seism noise,respectively.Results show that both earthquake events and micro-seism can be used as stable signal sources to estimate the relative sensitivity of the in-situ seismograph reliably for all three components including vertical,north-south and east-west and both the two methods exhibit a high consistency.For the in-situ seismograph which cannot be interrupted,the method proposed in this paper is an effective way to estimate the sensitivity of the seismograph in service.At four seismic stations tested,there are multiple components showing sensitivity errors larger than 3%at the Mengcheng and Jiujiang stations,and the sensitivity errors of the vertical and north-south components at the Mengcheng station are even close to 10%.Analysis suggests that the further work focused on the sensitivity investigation of stations from Chinese National Digital Seismographic Network is necessary and urgent,which would be significant for the improvement of seismic data quality in Chinese seismic observations.

关 键 词：同址比测 相关分析 灵敏度 在线地震仪 国家地震台网 

分 类 号：P315[天文地球—地震学]