黄河口凹陷浅层油气成藏模式的新认识及勘探效果——来自BZ28-2S油田勘探历程的启示

New Recognition of Shallow Oil and Gas Reservoir Forming Mode and Exploration Achievements in Huanghekou Sag——Enlightenment from Exploration Process of BZ28-2S Oilfield

BZ28-2S油田位于渤海南部海域黄河口凹陷中央构造脊,是中海油2006年发现的浅层优质中型油田,石油地质储量4500×104m3,油田于2009年投产,年产180×104m3。油田产层为明下段,埋深主要在900～1600m,明下段为浅水三角洲沉积,储盖组合良好。BZ28-2S油田发现历程曲折,20世纪80年代曾因毗邻构造浅层勘探失利终止了勘探,直至2005年在评价邻区BZ34-1等油田过程中积累了浅层油气成藏模式的新认识,BZ28-2S油田才迟滞24年之后终被发现。在BZ28-2S油田评价过程中也进一步验证了油气运移断层、中转站成藏模式、油层强振幅等钻前认识。BZ28-2S油田的发现历程再次启示勘探人员在老区勘探要用新思路才能找到油气。

BZ28-2S Oilfield is located at central structural ridge of Huanghekou Sag south of Bohai Sea.It is a high quality and middle size scale oilfield with reserves of 4500×104m3 that was found by CNOOC in 2006.Oilfield was produced in 2009 and had an annual production of 180×104m3.The main produced oil layer is lower Minghuazhen Formation.The burial depth of oil layers is about 900~1600m.The source-reservoir-seal assemblage of lower Minghuazhen Formation is good and belongs to shallow water delta.The discovery of BZ28-2S was devious.Exploration about this structure was terminated because the shallow targets of adjacent structure failed in 1980s.BZ28-2S Oilfield was found after 24 years later till the recognitions about the model of migration and accumulation was got during the evaluating of BZ34-1 Oilfield in 2005.These recognitions of fault of migration,transfer station model and high-amplitude in oil which were analyzed before drilling were verified during evaluating of BZ28-2S Oilfield.BZ28-2S Oilfield's discovery process inspired explorers again that new discovery could be got in old exploration field only the new thinking was taken.