云南地区强震前震源深度的时空展布

The spatial and temporal distribution of focal depth before strong shocks in Yunnan

通过对云南地区 1986年以来强震前中小地震的震源深度及时空特点的研究分析 ,找出震源深度的变化特性 ,深度异常与大震之间的关系。分析结果表明 ,强震发生的时间集中在震源深度首次出现 15km的 180天以内 ,而且深度异常形成的条带常沿断裂带分布 ,强震的震中区主要位于异常条带上或异常条带的延长线上。

By analyzing the spatial distribution of focal depth of small and middle earthquakes occurred before strong in Yunnan province since 1986, the characteristics of focal depth changes and the correlations between focal depth anomaly and strong earthquakes have been found. The results indicate that the occurring time of strong earthquakes concentrate within 180 days when the small or middle earthquake depths emerge first time at 15 km. The depth abnormal distribution formed a shape of stripe along fault zone. The epicenter region of strong earthquake is mainly located at the abnormal belt or at it′s prolonged line.