地震背景噪声中Lg波的提取  

Extraction of Lg-Wave from Seismic Background Noise

作　　者：丁文秀[1,2] 廖武林 李媛[1,2] DING Wenxiu;LIAO Wulin;LI Yuan(Institute of Seismology,CEA,40 Hongshance Road,Wuhan 430071,China;Hubei Key Laboratory of Earthquake Early Warning,48 Hongshance Road,Wuhan 430071,China)

机构地区：[1]中国地震局地震研究所,武汉市430071 [2]地震预警湖北省重点实验室,武汉市430071

出　　处：《大地测量与地球动力学》2021年第6期650-654,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震科技星火计划(XH19029YSX);中国长江三峡集团有限公司科研专项(0799216)。

摘　　要：以鄂、湘、粤地区27个宽频带测震台站2 a的连续波形数据为例,对单台每日的连续波形数据进行去除仪器响应、去趋势、去均值、剔除地震事件和干扰及滤波(2.5~8 s)处理后,在互相关叠加数据中识别出了清晰的Lg波。另外,尝试通过叠加时间长度校正及用双台双震源法对几何扩散、噪声源强度的方位角变化和场地效应进行校正,并计算Q值。研究结果表明,对传统的地震背景噪声数据处理方法作适当修改后,噪声互相关叠加数据中可以提取出Lg波。In this study,taking the seismic waveform data of 27 broadband seismic stations in Hubei,Hunan and Guangdong as examples,we improve the traditional background noise data processing,replacing the time domain and spectral whitening by eliminating seismic events and interference.After we remove instrument response,mean,trend,seismic events and interference,and band-pass filter(2.5-8 s)from the daily waveform data of a single station,the clear Lg-wave is identified from the cross-correlation and temporal stack data.We try to recover the relative amplitude of the Lg-wave by cross-correlation and stack time length correction,azimuth and geometrical spreading correction and site responses by reverse two-station method/two-event method.The research of this paper shows that the Lg-wave can be extracted from seismic background noise.

关 键 词：地震背景噪声 互相关叠加 LG波 振幅 信息提取 

分 类 号：P315[天文地球—地震学]