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渤海湾盆地的海域部分与渤海湾盆地其他部分一样,新生代为断陷-拗陷盆地.中渐新世以来,渤海湾盆地的沉积沉降中心迁移至渤海海域,并且拗陷期出现普遍的加速沉降现象.综合分析渤海各坳陷新生代构造样式和断裂时空展布特征,表明断裂发育总体受伸展控制,只是在中渐新世后受走滑影响.选取基本垂直渤海构造走向的6条大剖面,进行伸展量估算,并在剖面上选取虚拟井计算沉积沉降速率,结果表明,在断陷阶段,孔店组-沙四段沉积期,各坳陷沉积沉降速率较低且相差不大,发育多个沉积沉降中心;至沙三段沉积期沉积沉降速率达到最快,东营组沉积期沉积沉降速率变慢,但沉积沉降中心已从四周逐步迁移至渤中坳陷;拗陷阶段,以渤中坳陷为中心,出现的强烈沉积沉降,明显高于正常拗陷阶段沉积沉降速率.结合最新的深部探测资料,认为渤海新生代盆地的断裂展布,受中生代末先存的构造格局影响;断陷盆地的形成,则是太平洋板块俯冲的持续后退和印藏碰撞远程效应持续东进共同作用的结果;中渐新世以来的加速沉降现象,则是太平洋俯冲板片前缘向东迁移引起的岩石圈迅速冷却的最直接表现.
The Bohai Bay Basin has the same marine parts as the rest of the Bohai Bay Basin and the Cenozoic is a rift-depression basin. Since the Oligocene, the sedimentary subsidence center of the Bohai Bay Basin has migrated to the Bohai Sea, and the general accelerated sedimentation during the depression Phenomenon.A comprehensive analysis of the Cenozoic tectonic styles and distribution characteristics of fracture space-time distribution in the Bohai Depression indicates that the fault development is generally controlled by extensional control and is only affected by the strike-slip event after the Oligocene.The six vertical sections of the Bohai Sea, , The extension amount was estimated, and the virtual well was selected to calculate the depositional sedimentation rate. The results show that during the sedimentary period of the Kongdian Formation-Sha 4 Member, the depositional sedimentation rates of each depression are low and little different, Sedimentation and Sedimentation Center of Sediment in the Third Member of the Shahejie Formation is Sedimentary Sedimentation Rate of Sediment in the Third Member of the Shahejie Formation is Highest. Sedimentation and Sedimentation Rate of Dongying Formation Decreases in Sedimentation Period. However, Sedimentation and Sedimentation Center of the Sediment Deposition Center Has Gradually Migration from Four Weeks to Bozhong Depression. In the middle depression, the intense sedimentation and sedimentation is obviously higher than the sedimentation and sedimentation rate in the normal depression stage. Combined with the latest deep exploration data, it is considered that the fracture distribution in the Bohai Cenozoic basin is affected by The formation of faulted basins is the result of the continuous retreat of Pacific plate subduction and the continuous eastward collision of Indian-Tibetan collision. The accelerated subsidence phenomenon since the middle Oligoceses is the result of the Pacific Ocean The most direct manifestation of the rapid cooling of the lithosphere caused by the migration of the subducting plate front to the east.