川滇强震前地震活动空间扫描短期特征

对比分析了川滇地区近30年强震活跃段地震活动因子A值和空间集中度C值的全时空扫描结果.结果表明,川滇地区大地震孕育进入短期阶段时,震中周围地区的中小地震活动在A值和C值出现不同程度的变化,而且选取地震活动因子A值可更好地表征川滇地区的地震活动在时、空、强方面短期的综合特征.

Short-term seismicity characteristics before large earthquake obtained from the space-time scanning in Sichuan-Yunnan regions

Through the space-time scanning for the earthquakes occurred in Sichuan and Yunnan regions during the past 30 years,the seismicity factors A-value and the space-concentrating degree C-value are calculated.Their change images results show that in the period of 1-3 months before a large earthquake occurs,the seismicity factors A-value and the space-concentrating degree C-value about the small and moderate earthquakes appear some changes near the epicenter region.The seismicity factors A-value can express the comprehernsive situation of seismicity in Sichuan and Yunnan regions well.