尾波振幅比、时间熵及其应用的初步探讨

使用山东遥测台网1994－2000年（ML2.8-4.2级）间75次地震的300多条模拟地震资料和部分数字化资料，1）测定了尾波振幅比和能量比，并估算了山东地区的尾波值和平均自由程，进而试求了吸收品质因子Qi的散射品质因子Qs，得出山东地区地震尾波的衰减主要是由散射所造成；2）检验了用来定量描述尾波振幅随时间衰减状态的参数－－尾波时间熵ST，得出山东地区中强震前尾波时间熵下降是明显的，对中强震的预报效能是可行的。

Primary discussion on coda amplitude ratio,time-entropy and its application

Based on the simulated and digital earthquake records of 75 earthquakes recorded by telemetered seismic network of Shandong province from 1994 to 2000,the Coda amplitude ratio and energy ratio is determined, and the Coda Q-value as well as mean freedom distance in Shandong area is assessed.The absorption quality factor Qi and scattering quality factor Qs are also calculated.From those values we concluded that the attenuation of Coda wave in Shandong area was caused largely by scattering.Through examination to the parameter used to describe the attenuation of Coda amplitude with time(Coda time-entropy ST),we found that the attenuation of Coda time-entropy before medium and strong earthquakes is very clear,which may be useful in the prediction of medium and strong earthquakes..