利用体应变观测资料检测地球自由振荡  

Detection of earth’s free oscillation using volume strain observation data

作　　者：胡澜缤 李继业 张彦吉 王海涛 岳力 贾秀玲 HU Lanbin;LI Jiye;ZHANG Yanji;WANG Haitao;YUE Li;JIA Xiuling(Harbin Emergency Rescue Support Center,Harbin 150900,China;Heilingjiang Earthquake Agency,Harbin 150090,China)

机构地区：[1]哈尔滨市应急救援保障中心,中国黑龙江150900 [2]黑龙江省地震局,中国哈尔滨150090

出　　处：《地震地磁观测与研究》2021年第3期194-199,共6页Seismological and Geomagnetic Observation and Research

基　　金：中国地震局地震科技星火计划(项目编号:XH19011)。

摘　　要：选用通河地震台体应变观测数据,采用功率谱密度估计方法,获得2015年5月30日日本小笠原群岛地区8.0级大地震和2017年9月8日墨西哥沿岸近海8.2级大地震激发的0S4—0S35基频球型自由振荡频率,并与地球初步参考模型(PREM)的理论自由振荡频率进行对比,结果发现:前者共被检测到11个基频信号,有7个信号与理论值存在偏差,1个存在频谱分裂现象;后者共被检测到17个基频信号,有9个信号与理论值存在偏差,1个存在频谱分裂现象。Using body strain observation data at Tonghe Seismic Station and the power spectral density estimation method,the fundamental frequency spherical free oscillation frequencies of 0S4-0S35 excited by the magnitude 8.0 earthquake in the Ogasawara Islands area of Japan on May 30,2015,and the magnitude 8.2 earthquake off the coast of Mexico on September 8,2017,are obtained and compared with the theoretical free oscillation frequencies of the preliminary earth reference model(PREM).The results show that 11 fundamental frequency signals are detected for the former event with 7 signals deviate from the theoretical value and 1 signal has spectrum splitting;17 fundamental frequency signals were detected for the latter event with 9 signals deviated from the theoretical value and 1 signal has spectrum splitting.

关 键 词：体应变 大地震 地球自由振荡 球型振荡 

分 类 号：P315.7[天文地球—地震学]