【摘要】 １９９８年１月１０日发生在张北的６．２级强震，是华北地区自１９８９年大同６．１级震群后的又一次较为显著地震。在汇总首都圈及其周围地区各种前兆异常的基础上，研究了近震区（２００ｋｍ范围内）前兆异常的空间、时间演化特征。结果表明，前兆异常的发展过程存在较明显的阶段性和成组性，反映了震前区域应力场的增强过程。还对这些前兆异常的机制进行了探讨。更多还原

【Abstract】 Zhangbei Ms 6. 2 earthquake (41. 1°N, 114. 3°E) on January 10, 1998 was an- other eminent event after Datong Ms 6.1 shock in 1989 in North China. The spatial and temporal characteristics of anomalies nearby epicenter (△≤200 km) show that anomalies occurred in groups and by stages, reflecting the strengthening process of field stress.Pri- mary discussion on anomaly mechanism is also given in the paper.更多还原