苍山5.2级地震前测震学参数的异常分析

利用山东省地震台网的地震资料，分析研究了鲁南地区１９９１～１９９５年地震波速比的时空变化、地震活动性参数及加卸载响应比。研究发现苍山５．２级地震前，该地区的波速比时空变化出现了明显的低值异常；地震活动出现３、４级地震集中；应变能释放速率加速、转平；加卸载响应比在震中及邻近区域出现高值等明显异常，并分析了某些异常的发展及转化过程，提出了某些短临异常指标。

ANALYSIS FOR SEISMIC PARAMETER ANOMALY BEFORE CANGSHAN EARTHQUARE OF M s 5 2

The time space variation of the velocity ratio of seismic wave, seismicity prarmeter and ratio between loading and deloading in thd south region of shandong from 1991 to 1995 are analysed and studied using seismic network data of Shandong Province. It is found that there were the obvious low value anomaly of wave velocity ratio, the concentration of M s 3～4 earthquakes, increase of the release ratio of strain energy and then turning into smoothing, and the obvious high value anomaly of loading deloading response ratio in the epicentre and adjacent area before the Cangshan earthquake of M s 5 2. The development and variational processes of certain anomalies is analysed, and certain indices of the short imiminent anomaly are presented.