根据重磁资料解释河北断裂体系与地震地质构造

Interpretation of Hebei fault system and seismogeological structure based on gravity and magnetic data

河北省是我国主要的强震发生区,研究区内的地震地质构造对认识地震灾害具有重要意义。笔者根据1∶20万区域重力、1∶20万~1∶5万航磁资料,采用小波多尺度断裂分析方法,研究河北断裂体系,并应用于地震地质构造分析。重点分析了1966年邢台7.2级、1976年唐山7.8级及1679年三河—平谷8级地震的发震断裂特征,发现新河断裂、唐山断裂与夏垫断裂,其浅部断裂与深部断裂关系密切,邢台7.2级地震的浅部断裂与深部断裂平面位置重叠,邢台7.2级地震是下部深断裂与浅部信合断裂共同作用的结果。本次研究指出,重力航磁资料处理解释是研究地震地质构造的一种有效、快捷及经济的方法,它能够为地震地质构造研究提供重要的信息。

Hebei Province is one of the major areas where strong earthquakes occur in China,and the study of seismic structures in this area is of great significance to the understanding of earthquake disasters.Based on the 1∶200000 regional gravity and 1∶200000~1∶50000 aeromagnetic data,the fault system in Hebei Province is systematically studied by using the wavelet multi-scale fault analysis method,and applied to seismological structure analysis.The characteristics of the seismogenic faults of the 1966 Xingtai M7.2,1976 Tangshan M7.8 and 1679 Sanhe—Pinggu M8 earthquake are emphatically analyzed.It is found that the shallow faults of Xinhe fault,Tangshan fault and Xiadian fault are closely related to the deep faults.The plane position of shallow faults overlapped with the deep faults of the Xingtai M7.2 earthquake.The Xingtai M7.2 earthquake is the result of the joint action of the lower deep faults and the shallow Xinhe fault.It is concluded that the processing and interpretation of gravity and aeromagnetic data is an effective,fast and economical method for studying seismogeological structures,which can provide important information for the study of Seismogeological structures.