地震与核爆识别的小波包分量比方法  

Application of method of spectral component ratio of wavelet-packets to discrimination between earthquakes and nuclear explosions

作　　者：杨选辉[1] 沈萍[2] 刘希强[3] 郑治真[4] 

机构地区：[1]中国地震局地壳应力研究所,北京100085 [2]中国地震局地球物理研究所,北京100081 [3]山东省地震局,济南250014 [4]中国地震局地震信息中心,北京100045

出　　处：《地球物理学报》2005年第1期148-156,共9页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目 (4 9744 0 0 6)资助

摘　　要：频谱分析法在核爆与地震识别中具有广泛的应用 .但是频谱分析方法是稳态方法 ,即使采用Gabor变换 ,也因时_频窗口形状不变而分辨率较低 .为提高时_频分辨率 ,本文将小波变换理论用于乌鲁木齐台记录的地震与核爆事件的分析 ,并提出了识别核爆和天然地震的小波包分量比判据 .通过对加拿大黄刀地震台记录的印度地下核爆的分析 ,进一步验证了小波包分量比判据对核爆和地震的识别具有较高的识别效率 .结果表明 :对于地震信号 ,其小波包分量比U03 U13一般都大于 1 0 ,而对于核爆信号 ,比值U03 U13一般都小于 1 0 .The spectral analysis method is widely used in discrimination between nuclear explosions and earthquakes. As a stationary method, it has low resolution due to its invariable time_frequency window, even if the Gabor transform is adopted. To improve its resolution, a wavelet transform is applied to the analysis of earthquakes and nuclear explosions, which were recorded at the rümqi seismic station in the Xinjiang Autonomous region. And a criterion of spectral component ratio of wavelet_packets (SCRWP), which is used to identify the earthquakes and nuclear explosions, is proposed. Analysis of data of the India nuclear test recorded by the Yellow Knife Seismic Array in Canada has also confirmed that the SCRWP method is rather effective in discrimination between nuclear explosions and earthquakes. The result shows that the SCRWP value U\+0\-3/U\+1\-3 is generally higher than 1 0 for earthquakes, but usually less than 1 0 for nuclear explosions.

关 键 词：小波变换 小波包分量比 识别 地震 核爆 

分 类 号：P315[天文地球—地震学]