菏泽5．9级地震前后三项地震活动性参数的空间动态演化

THE TIME AND SPACE DYNAMIC EVOLUTION OF THREE SEISMICITY PARAMETERS BEFORE AND AFTER THE HEZE M5. 9 EARTHQUAKE

用地震活动性参数（地震频度Ｎ、地震能量Ｅ和地震ｂ值）的二维空间等值线计算机扫描技术，系统地追踪了１９８３年菏泽５．９级地震前后三项地震活动性参数的空间动态演化情况。结果表明，菏泽５．９级地震前１—４年，河北平原断陷南部地区特别是其东界聊考断裂带地震活动异常增强，地震频度增高，地震能量释放加速而地震ｂ值降低；地震活动增强区的长度约２００余公里，未来主震发生于地震活动增强区的边缘；震后约一年左右震中周围地震活动趋于正常。地震活动性参数二维等值线的上述变化，较清晰地显示了１９８３年菏泽５．９级地震前后震中周围地区地震活动性空间域的演化全貌，有助于地震孕育过程中近场异常信息的提取与动态监视，进而可能实现强震震源发展过程的追踪。

By computer scanning technique of two-dimensional space isogram of seismicity parameters (seismic frequency N, seismic energy E and b-value), we systematically traced the space dynamic evolution process of three seismicity parameters before and after the 1983 Heze M5. 9 earthquake. The result shows that before the Heze M5. 9 earthquake in the southern region of Hebei Plain fault and especially in Liaokao fault zone on its east boundary, the seismic activity exceedinyly increased, seismic frequency raised, seismic energy release accelerated and b-value decreased ; the length of the region where seismic activity increased is more than 200km, the coming major earthquake occurred on the margin of theseismic activity increased region about one year after the earthquake, the seismic activity arround the epicenter turned to normal. The above variation of two-dimensional isogram of seismicity parameters clearly shows the whole space evolution process of the seismic activity around the epicenter before and after the 1983 Heze M5. 9 earthquake, this contributes to extraction of near-field anomalous information during earthquake preparation and to dynamic monitoring and then can trace the source developing process of strong earthquakes.