强震前的小震活动增强图象研究

以地震破裂理论和大震前区域地震活动水平增强事实为依据，选取地震频次和应变量两个统计参数，对新疆境内天山北缘、南缘地震带和西昆仑地震带共７５平方度区域进行时空扫描。根据两个参数与其前３年均值之比的大小组合，确定小震活动增强区，并分析其与目标地震的对应关系，提出地震预报判据。通过Ｒ值评分检验，说明小震活动增强图象方法具有较好的中期地震预报效能。

THE STUDY ON INCREMENT OF SMALL SEISMICITY PATTERN BEFORE STRONG EARTHQUAKE

Based on the seismic rapture theory and the increasing regioncl seismicity before large earthquake, author selected the seismic frequency and strain as two statistic parameters to scan the three seismic zones within Xinjiang region,and determines the increment region of small seismicity by the combination of the ratio of the parameter's value to the average value of three years before the calculating year,and analyses the correlation between the large earthquake and the increasing region,and finally puts forward the prediction index. The method of increment of small seismicity pattern has a good efficiency in meddle-term earthquake prediction by the evaluation examination of R value.