东营凹陷南坡盆缘地层圈闭油气成藏机理和地质风险评价方法的研究.pdf

摘要本文在总结前人研究成果的基础上,综合利用地质、地球化学、地球物理等资料, 以东营凹陷南坡盆缘地层圈闭为研究对象,深入分析金家油田、高青油田古近系地层不整合遮挡油藏和乐安油田新近系地层超覆油藏的形成条件及成藏主控因素,明确了地层超剥带和鼻状构造带是东营凹陷南坡地层油藏的有利富集区带,并建立了两套地质风险评价标准。地层超剥带型地层油藏的分布受控于圈源距离、储层物性、地层倾角、其次为盖层厚度与质量。随着油藏与高青断层距离的增大,油藏油柱高度有减小的趋势;在其它条件相同的情况下,各含油区块的运移阻力(输导层物性)影响油气横向运移的最大距离; 地层倾角越大含油高度越高;盖层厚度越大、质量越好,所封堵油气的能力就越大。鼻状构造带型地层油藏的分布受控于构造脊、断层活动性、砂体厚度以及盖层岩性与质量。;成藏期断层的活动性对油气的聚集成藏起重要作用:砂体厚度控制着地层油藏的平面展布;大段致密的火成岩能起到封堵油气的作用,可作为局部性盖层。确立不同类型地层圈闭的成藏主控地质条件,明确其对油气成藏影响作用的大小。根据研究区盆缘地层圈闭勘探实践数据,进行归类统计,建立各成藏地质要素的分级评价取值范围,确定各项成藏要素权系数值。对油源、输导、圈闭、封盖等主要成藏条件分别赋值,采用模糊评价的方法对研究区地层圈闭地质风险进行综合评价,建立地层超剥带、鼻状构造带两种类型盆缘地层圈闭地质风险评价标准,并运用勘探实践资料对本标准进行校验,提出有利圈闭勘探地区。关键词:东营凹陷南坡,圈源距离,构造脊,主控因素,成藏模式,地质风险评价 Hydrocarbon accumulation mechanism andgeologic risk luationofbasin stratilgraphic tra southernevaluation olbas|n margin straUgrapmc trap on utnern slope ofDongying depression LiuYing(Investigation andExploration ofMineralresource) Youlu Abstract Based onthesummarization ofprevious research results,and 011the prehe· nsive utilizationofgeological andgeochemical,geophysical data.,Through analysing the formation tracelgeological characteristics,forming conditions and accumulation process of Jinjia,Gao qing and Le allstratigraphic reservoirs indifferent layer series on thesouthern slope inDongying depression tofindmain controlling factorsofhydro。carbon accumulation ofbasin marginstratigraphic trap ondifferent structural belts. Distribution ofstratigraphic reservoir on stratigraphie ultra-denudation zone ismainly controlledby distancefrom source totrap,reservoir physicalproperties,formationdip,and thickness and qualityofcap height reduce along with thedistance increases between reservoirand Gao qing fault anditincreasesfollowing themagnify offormationdip; Migration distance ofoilandgas increasesalong withthemagnify of thereservoirporosity; Thickness andquality enhance thesealing ability ofcap rock. Distributionofstratigraphic reservoir on nose struc