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分析研究了渤海及周围地区断裂构造和强震活动特征 ,初步探讨了渤海及周围地区的地球动力学问题。结果表明 ,渤海及周围地区断裂和地震活动存在着内在的成生联系 ,其突出特征是时空上的非均匀性。断裂和地震活动在空间上具有成带、分段、分区和衰减特征 ;时间上 ,晚更新世晚期 (2— 3万a)是断裂整体活动时期 ,全新世断裂活动强度减弱 ,范围缩小 ,粘滑破裂具有上千年的周期 ,15 0 0年以来地震活动呈活跃与平静的交替。板块运动产生的区域北东东向挤压应力和渤海上地幔隆起及其产生的构造应力联合作用 ,控制着渤海及周围地区的断裂和地震活动。分析认为 ,渤海及周围地区未来相当长时间内 (百年尺度 )发生 6级地震的可能性不大。
The characteristics of fault structure and strong earthquakes in the Bohai Sea and its surrounding area are analyzed and studied, and the geodynamic problems in the Bohai Sea and the surrounding area are discussed preliminarily. The results show that there is an inherent relationship between the fault and seismic activity in the Bohai Sea and the surrounding area, and its salient feature is the temporal heterogeneity. Faults and seismic activities are characterized by zoning, segmentation, zoning and attenuation. In time, Late Late Pleistocene (2-300 a) is the period of the whole fault activity. During the Holocene, the activity intensity of the faults is weakened and the range is narrow. Slippery ruptures have a period of thousands of years, and seismic activity has been active and calm since 1500. The northeast-east compressive stress in the area produced by the plate motion and the uplift of the upper Bohai Sea and the tectonic stress caused by the tectonic stress combine to control the fault and seismic activity in the Bohai Sea and surrounding areas. The analysis shows that there is not much possibility that a magnitude 6 earthquake will occur in the Bohai Sea and surrounding areas for a long time (on a century-scale scale).