【摘要】 渤海海域油气勘探经历了40多年的曲折历程,原油垂向分布规律及控制因素的复杂性制约了其勘探进程。基于断裂活动、烃源岩演化与区域盖层的研究,对全区已发现油藏的垂向富集规律及其控制因素进行了深入的分析。结果表明,(晚期)新构造运动对原油成藏与分布起到主导作用。通源断裂垂向输导原油的能力与其活动速率有关,活动速率小于10m/Ma的断裂输导能力弱,主要起封闭作用;活动速率为10~25m/Ma的断裂起到输导与封闭双重作用;活动速率大于25m/Ma的断裂主要起输导作用。晚期断裂活动速率、活跃生油岩与区域性盖层的发育分布及其时空配置关系,共同控制了古近系、新近系原油的富集与贫化。并归纳了渤海海域古近系、新近系4种原油富集/贫化模式,即古近系富集模式、古近系与新近系共同富集模式、新近系富集与古近系贫化模式以及新近系贫化模式。更多还原

【Abstract】 Petroleum exploration has been carried out for more than 40 years in the Bohai sea,however,weak understanding for the hydrocarbon vertical-occurrence mechanism and controlling factors in this area has seriously restricted exploration programs.The present paper intensively investigated different hydrocarbon accumulations and controlling factors based on studies on faulting activities,evolutions of source rocks and regional caprocks in all the discovered oil fields across the area.The result showed that faulting activities during Neotectonism played the most important role in hydrocarbon accumulations and vertical occurrence.The potential conducting hydrocarbon migration along faults was probably dependant upon fault activity rate(FAR).Once FAR<10m/Ma,little or none of hydrocarbons migrated along faults,in contrast,mass flux of hydrocarbons moved along faults when FAR25m/Ma.The faulting activity rate at the late stage,combined with active source rock distributions and caprock occurrence and together with their spatiotemporal match during Neotectonism had controlled hydrocarbon enrichment/depletion in the Paleogene or/and Neogene.Thus,four models were established on the basis of FAR,i.e.a Paleogene oil-enrichment model,a Paleogene and Neogene oil-enrichment model,a Neogene oil-enrichment but Paleogene oil-depletion model and a Neogene oil-depletion model.All the models are valuable in selecting payable zones or targets within both the Paleogene and Neogene of this area.更多还原