根据近41年的现代地震资料,利用地震活动性参数组合、b值空间分布、断裂带分段,并结合历史强震构造背景的综合分析方法,分析了河北平原地震带各分段落的现今地震活动习性和地震危险性。研究结果表明:河北平原地震带存在着7个具有不同现今活动习性的分段落,其中,唐山—迁安段和东明—阳谷段处于低b值、高应力状态,但经过分析这种现象是属于大震后晚期余震活跃或断层震后调整运动结果;昌平—宝坻、天津—肃宁段、新河段、邯郸—磁县及汤西段断层面现今活动习性均处于相对低应力下的频繁或稀疏小震滑动。因此,河北平原地震带未来短期内发生强震的可能性较小。
According to seismic datas recorded in the last 41 years and by using combination of seismic activity parameters, b value spatial distribution, fault division combined with historical background, the modern activity characteristics of the different sections which belong to the Hebei plain seismic belt are analysed. The analysis results show that there are seven sections of the Heibei plain seismic belt with different modern seismic activity characteristics. The Tangshan—Qian’an section and the Dongming—Yanggu section are in a state of low b value and high stress, because of active aftershocks triggering by major earthquakes in late period or fault adjustment after large earthquakes; modern activity characteristics of the Changping—Baodi, Tianjin—Suning, Xinhe, Handan—Cixian and Tangxi section are at the relatively low stress level, small earthquakes have occurred frequently or sparsely. Consequently, the probability of huge earthquakes in future of the Heibei plain seismic belt is small.