用不等间距统计法对唐山余震序列的研究

采用不相等间距统计方法，研究唐山余震序列。方法一是直接、间接余震法；方法二是震间地震活动法；方法三是对数时间间隔法。用这些方法研究整个余震序列，研究了强余震瓣的趋势和短临变化，得到一些有预报意义的特点和指标。不等间距统计在法在地震预报中存在着重要作用。

STUDY ON TANGSHAN AFTERSHOCK SEQUENCE BY METHOD OF UNEQUAL INTERVAL STATISTICS

By using the methods of unequal interval statistics, the authors studied the Tangshan aftershock sequence in this paper. These methods include: the direct- indirect aftershock method, shock-to-shock seismic activity method and logarithm time interval method. Based on studying the whole aftershock sequence, the trend and the short-term and impending precursors before the strong aftershock, and seismicity in its source field, some seismic precursory characteristics and prediction indices are obtained. The results show that methods of unequal interval statistics are of great importance in earthquake prediction.