中文摘要：

对人工地震剖面结果进行综合分析和插值处理，得到了渤海及邻近区域的地壳厚度图，并结合其他地球物理结果，对1969年至1976年在渤海及邻区发生的3次7级以上大地震的深部构造背景提出了一些初步看法：渤海地区为一上地幔隆起中心，最薄处地壳厚度只有28km；同时，该地区也是高热流值中心、地壳垂直形变中心和居里面上隆中心；隆起区为一北北东向条带，与郯庐断裂位置相吻合；渤海、海城和唐山3个大地震均发生于该隆起区的边缘，可能与上地幔隆起作用所引起的应力场和热异常活动所引起的热应力场有关。

英文摘要：

Through synthetic analysis and interpolation to the results of deep seismic sounding profiles, the crustal thickness graph of Bohai sea and its adjacent region is obtained. Combining with other geophysics results, some opinions about deep structure background of three Ms 〉 7.0 strong earthquake in Bohai sea and its adjacent region during 1969 to 1976 are proposed that the Bohai region is the center of upper mantle upheaval, where the thinnest crustal thickness is only 28 km; furthermore, this region is also the center of high thermal flow, vertical deformation of crust and the Curie surface upheaval and the raised region is a NNE-striking belt and is corresponding to the strike of Tancheng - Lujiang fault belt. The Bohai earthquake, the Haicheng earthquake and the Tangshan earthquake all occured in the edge of the raised region and it maybe related to the stress field caused by the upper mantle upheaval and the thermal stress field caused by the abnormal thermal activities.