Abstract: The offshore area is an important part of Bohai Bay Basin.It is the extensions of three depressions,Jiyang,Huanghua,and Lisohe depressions,in the offshore area.Evolution histories of offshore sags are similar to those of the onshore ones.The rising of mantle and the framework of the three surrounding mountains have controlled the formation of the sags,which are controlled by extension faults,instead of strike-slip faults.Tanlu fault does not have great influence on the sedimentary processes in sags.Bozhong sag is different from others,the Dongying formation in which is much thicker and possesses great hydrocarbon generation potential.In the offshore area of Bohai Bay Basin,there are four sags with great hydrocarbon generation potential (Lisozhong,Bozhong,Qikou,and Huanghekou sags) and five exploration fields (uplifts and their plunging ends,shallow structures,buried hills and faulted pre-Tertiary structural plays and slopes of sags).The offshore resources potential is the same large as the three onshore depressions.The offshore area of Bahai Bay Basin has good future in exploration and will become a followup exploration area in East China.

Key words: depression, evolution, earth mantle, oil and gas resources, Bohai Sea

摘要： 渤海是渤海湾盆地的重要组成部分,是济阳、黄骅、辽河三大坳陷向海域的延伸与交汇,海域各凹陷的发育演化与防区基本一致.凹陷的变迁主要受控于地幔的洪升及周边三座大山格局.控凹断裂是伸展断裂,而不是走滑断裂,郯庐断裂对凹陷的沉积控制作用不明显.渤中凹陷有别盆地诸凹陷,沉积巨厚的东营组,并显示了良好的富生烃前景.海域有四大富生烃凹陷(辽中、渤中、岐口、黄河口).有五大勘探领域(凸起浅层及倾没端、浅层构造、古潜山及前第三系、断裂构造带、凹陷的斜坡带).海域潜在的资源量可与陆区三大坳陷媲美,寻找油气前景广阔,是我国东部陆区的接替战场.

关键词: 坳陷, 演化, 地幔, 油气资源, 渤海