北黄海盆地中新生代沉积坳陷特征及其油气勘探方向

The character ofmid-cenozoic sedimental depression and oilgas explorating direction in north Yellow Sea.

广州海洋地质调查局, 广州510760

Guangzhoumarine Geological Survey, Guangzhou 510760, China

北黄海盆地属中-新生代含油气盆地,地质构造复杂,我国在该区的油气勘探一直未见成效,2002年开始对盆地进行了较为系统的综合地球物理调查。对北黄海盆地沉积坳陷的基本特征进行了描述——盆地由一系列中、新生代断(坳)陷构成,位于盆地北部的东部、中部和西部坳陷是盆地的主体沉积坳陷,最大沉积坳陷面积超过2200 km²,最大沉积厚度达9000m,其中中生界最大厚度达4800m;盆地南部则分布了一些规模较小的断陷。对油气勘探前景进行了分析——根据朝鲜的钻探资料,北黄海盆地中生界的白垩系和侏罗系是主要勘探目的层,而盆地东部坳陷的中生界厚度大,烃源岩条件好,各种类型的局部构造圈闭发育,且既有区域性盖层又有局部盖层,生储盖条件优越,因此,东部坳陷应是盆地油气勘探前景最好的区域。

The northern Yellow Sea basin is a petroleum-bearing basin ofmid-Cenozoic era, Petroleum exploration has notmade satisfying progress in this basin due to its complicated geological structure.Systemic geophysical survey has been executing since 2002.Exploration data shows that this basin consists of a series of fault depressions.The eastern, themiddle and the western depressions aremain sedimentary depressions, of which themaximum area ismore than 2200km² them, themaximum sedimentary thickness of depressions is 9000m while themaximum sedimentary thickness ofmid-Mesozoic group is 4800m.Themain exploration target is focusing on the stratum of Cretaceous and Jurassic, the eastern depressions is themost promising area for exploration for its favorable condition of hydrocarbon source rock and completed traps.