【摘要】 震前预滑是预报大震的物理基础之一。在强的构造压力作用下形成的震源，预滑较显著。在构造引张作用下形成的震源，预滑易和发震本身紧连在一起。大地震（Ｍ≥７）发生时在地表形成的错动可分三种类型：第一种是在震中区局部地段有错动；第二种是在地表与震源长度相当的地段有错动但中间部位位移较大；第三种是在地表与震源长度相当的地段有错动但位移大小到处几乎相当。按照组合模式，可将地震前兆分为震源区前兆、调整单元和调整场区前兆、震源外围更大范围区域应力场前兆。对地震三要素的预报来说，最重要是前二种前兆，第三种前兆可作参考。更多还原

【Abstract】 Pre-earthquake creeping is a physical base for predicting big earthquake. For the earthquake source formed under high tectonic pressure, the pre-earthquake creeping is more obvious. For the earthquake source formed under tectonic tension, the pre-- earthquake creeping is favorable to closely join with the dislocation of earthquake occurrence time. When big earthquakes (M≥7) occur,their coseismic faults on earth’s surface are classified as three types: ① The coseismic faults only appear in a small segment in epicen- ter area. ② It appear in a length, which is equal to the fault in earthquake source, but its displacement is bigger in middle part in earth’s surface. ③ The length of coseismic fault is equal to that in earthquake source, and its displacement is almost same in whole length on earth’s surface. According to the combination model, area displaying precursors may be divided as that: the precursors display in source region, in adjustmental elements or adjustmental field, and in more wide extent around the source which is corresponding to regional stress field. For predicting earthquake’s time, location and magnitude, the first two are the most important, the third can be referred for prediction.更多还原