【摘要】 从研究震前大范围的调制比异常出发，定义了调制块比的概念，并研究了国内的某些震例。结果表明，调制块比平均异常时间１．２５年，平均异常开始至发震时间２． ０年，平均异常结束至发震时间１．０年，调制块比异常对７级以上地震显示为高值异常特点。另外，调制块比可反映部分地震前的中期地震活动性异常。当地震孕育到中期阶段时，震源周围地区出现小震调制比异常区域增加的异常。更多还原

【Abstract】 On the basis of microseismic modulating ratio’s concept, we defined modulating blocks ratio. It can reflect variation of earthquake field. Taking some earthquakes as ex- ample, we conclude that modulating blocks ratio is a medium-term anomaly occurred 1-2 year before strong earthquakes. Anomaly mechanics of modulating blocks ratio is related with local strain field concentrated and strengthen. They can be easily modulated by solid tide.更多还原