地震波动力学特征变化指标在短期地震预报中的应用  

APPLICATION OF VARIATION INDEX OF SEISMIC WAVE CHARACTERISTICS TO SHORT-TERM EARTHQUAKE PREDICTION

作　　者：冯德益[1] 吴国有[1] 陈化然[1] 郭瑞芝[1] 虞雪君 丁伟国[3] 

机构地区：[1]天津市地震局,中国天津300201 [2]浙江省地震局,中国杭州310007 [3]上海市地震局,中国上海200062

出　　处：《地震》1994年第1期12-22,共11页Earthquake

摘　　要：本文研究大地震前地震波动力学特征的变化,主要是波形和频谱的变化,并从中提取出可望在短期(半年以内)地震预报中应用的一些预报指标。这些指标包括:P波初始部分波形的时间线性度和空间线性度,初始段平均半周期,S、P波频谱的峰值频率、拐角频率、相对频带宽度、相对频谱峰值、高频段的谱线斜率绝对值等。同时还研究了短周期地脉动的波形线性度及频谱特征量(峰值频率等)在大震前出现的短期(半年以内)和临震(9天以内)的前兆异常变化,发现其波形时间线性度与空间线性度、平均半周期及频谱的最大频率、峰值频率、拐角频率等的前兆异常变化明显,因而可作为短临地震预报指标。 本文所提出的地震波动力学特征变化指标已经过1990年青海共和6.9级地震、1989年10月山西大同6.1级地震、1990年常熟5.1级地震、近年来唐山老震区的几次4.5级左右地震以及1975年海城7.3级地震和(1976年唐山7.8级地震的震例分析检验。The variations of dynamic characteristics, mainly the form and spectrum pf seismic waves before large earthquakes have been studied, and some prediction indices among which, some may be prospective in application to short-term(within half year) earthquake prediction, are found. These indices include: temporal and spatial linearity of wave form of initial part of S,P wave, its average half-period, the peak frequency, corner frequency, relative width of frequency domain, relative value of peak spectrum and the absolute slope value of high frequencies.At same time, it also analysed short-term(half year) and impending(9 days) precursory variations of linearity and spectral characeristics of short-term microseism waveform. And found precursory variations of linearity and spectral characteristics,average half-period,peak frequency,maximum frequency, corner frequency is obvious. Therefore, they may be considered as the indices for short-term and impending earthquake prediction.All the prediction indices of dynamic characteristics variation of seismic waves given in this paper are checked through Gonghe MS6.9 earthquake on April 26, 1990; Datong As6.1 earthquake on Oct. 19, 1989; Changshu MS5.1 earthquake on Feb 9, 1990 and some moderate earthquakes with MS4.5 occurred in recent years in Tangshan region,and partly through the Haicheng earthquake AS7.3 in 1975 and Tangshan earthquake MS7.8 in 1976.

关 键 词：地震预报 地震波 动力学 变化指标 

分 类 号：P315.7[天文地球—地震学]