系统研究了宁夏及邻区35次小震群活动，总结了震群活动的参数特征，探讨了震群活动与中强以上地震的关系，分析检验了前兆震群类型的判定指标。1970年以来宁夏及邻区35次小震群中有10次对应了5级以上地震，灵武-吴忠地区利用震群预测5.0级以上地震的效果较好，不建议利用震群预测宁夏南部及邻区5.0级以上地震。通过前兆震群类型的判别判断后续是否有中强以上地震，总体而言效果并不十分理想，需要参考其它方法和手段综合判定。

We systematically analyzed 10 out of the 35 earthquake swarms in Ningxia and its adjacent area,summarized the characteristics of earthquake swarms and discussed the relationship between earthquake swarms and medium-strong M ≥ 5.0 earthquakes in Ningxia and its neighboring area since 1970. Swarm forecast is recommended for M ≥ 5.0 earthquakes in the Lingwu-Wuzhong region but not for M_S ≥ 5.0 earthquakes in southern Ningxia and its neighboring area. Whether there is a subsequent medium-strong earthquake,the general effect of the swarm precursor discrimination is not very good and need the reference to other methods and means.

P315

宁夏回族自治区科技攻关计划项目（2013ZYS145）资助