鄂东襄樊-广济断裂黄州段未来地震 危险性分析

通过对鄂东襄樊-广济断裂黄州段的地质构造、第四纪活动性、地震活动和现今地壳变形的分析,综合判定该段断裂的活动性和构造特征。该断裂是中国东部地区典型的弱-中等活动断裂。采用地震构造类比法和矩震级经验关系,综合评估了断裂的未来可能最大发震震级为6. 0级;利用历史和现今地震活动资料,建立了按500 a归算的震级-频度关系,采用泊松概率模型,计算得到襄樊-广济断裂黄州段未来50～200 a地震平均复发间隔和发震概率等定量参数。该成果可为区域地震危险分析及工程抗震设防提供参考。

Seismic Risk Analysis in Huangzhou Section of Xiangfan-Guangji Fault in the Eastern Hubei

Based on the analysis of geological structure, Quaternary activity, seismic activity and recent crustal deformation in Huangzhou section of Xiangfan-Guangji fault in the eastern Hubei, the activity and tectonic characteristics of the fault were determined synthetically. The result shows this fault is a typical weak-medium active fault in the eastern part of China. Then the seismic structure analogy and moment magnitude empirical relationship were adopted to evaluate the possible maximum seismicity of the fault, which is Ms6.0. Historical and modern seismic activity data were used to establish a magnitude-frequency relationship model by 500 years. Finally the Poisson probability model was utilized and quantitative parameters such as recurrence period and occurrence probability of Huangzhou section of Xiangfan-Guangji fault in the coming 50 to 200 years were calculated.This result can provide a reference for regional seismic hazard analysis and engineering seismic fortification.