歧口凹陷歧北低斜坡B90井区沙一下油气成藏条件研究

歧口凹陷歧北低斜坡B90井区,油气藏发育广泛,沙一下是该区勘探开发的重点。对研究区,沙一下油藏基本特征进行研究,分析其成藏条件,从而指导油气勘探。研究区油藏类型可分为构造-岩性油藏及岩性油气藏两种。研究区地层埋深较大,烃源岩成熟,生烃条件良好、源储一体,油气运移动力强。在运聚方向上的上倾尖灭砂体捕获油气而成藏。研究认为,B90井区,连接歧南、歧北斜坡,砂体叠置发育,连片分布,物性好,形成岩性上倾尖灭的岩性圈闭。这种岩性圈闭厚度大、条件好产量高,是大港油田重要的增储上产地区。

Study on the conditions of petroleum accumulation in the lower part of the first member of Shahejie Formation in B 90 well area of Chengbei Low Fault of Qikou Depression

In B 90 well area of Chengbei Low Fault of Qikou Depression,hydrocarbon reservoirs develop widely.The lower part of the first member of Shahejie Formation is the focus of exploration and development in the area.In the study area,we study the reservoir characteristics of the lower part of the first member of Shahejie Formation,analyse its forming conditions,then guide the oil and gas exploration.The types of the reservoirs can be divided into structural lithologic reservoirs and lithologic oil and gas reservoirs in the study area.In the study area,Stratigraphic buried deep,hydrocarbon source rock maturity,good hydrocarbon generation conditions,source reservoir body,good hydrocarbon migration dynamics.In the direction of the updip pinchout sand body capture oil and gas and then accumulat reservoirs According to the study,B 90 well area,which connects Qinan and North Qikou.Its sand body overlapping development,regional distribution,good physical property,which form a rock of updip pinchout lithological traps.This kind of traps,large thickness,good traps condition,high output,which is important for increase production in dagang oilfield.