松辽盆地太东斜坡区葡萄花油层油水分布规律及主控因素

Oil distribution rule and main controlling factors of Putaohua reservoir in Taidong slope,Song-liao basin

太东斜坡区为松辽盆地大庆长垣向三肇凹陷倾没的单倾斜坡.利用岩心、测井和地震等资料,研究葡萄花油层油藏类型和油水分布规律.结果表明:斜坡区油平面受4条近南北向"断层带"分割,具有东西分带特征,且受源外油源供给不足和油东西向运移影响,自东向西单一"断阶带"含油性逐级变差;油垂向分布受沉积演化和优势输导通道控制表现为"双峰"特征,主要分布在葡萄花油层中部;油藏类型主要为东南倾斜坡背景下的近南北向断层与北西向河道砂体匹配形成的断层—岩性油藏.在油水分布规律研究的基础上,结合单一圈闭内断层与单砂体匹配样式,提出源外斜坡区油聚集机制受构造部位、优质储层、断层封闭性和断层与砂体匹配样式控制,即单一"断阶带"高点控制油气聚集部位;浅水三角洲水下分流河道和河控席状砂构成油气优质储层;断层侧向封闭性影响油气垂向富集高度和平面"互补"特征;断层与单砂体匹配样式决定油气富集层位.

Taidong slope area is the single slope where Daqing placanticline plunge to Sanzhao sag in Songliao basin.Using data as core,logging,and seism,we study reservoir types and hydrocarbon distribution rule in Putaohua reservoir and get the following conclusions:The slope area oil layers are divided by four nearly north-south trending fault zone in plane and have the feature of east-west zoning.Because the oil source outside the source area is insufficient and the east-to-west migration trending,oil-bearing in single fault terrace zone became worse gradually from east to west.Controlled by sedimentary evolution and advantage conducting channel,the vertical distribution of oil presents the feature of 'double peaks' and mainly distributed in central Putaohua reservoir.Under the background of SE tilt slope,the oil reservoir type is mainly fault-lithologic reservoir matched by nearly north-south trending fault and north-west trending channel sand body.According to the matching type of fault and channel sand body in single trap and the study of oil and water distribution rule,we think the accumulation mechanism is controlled by structural parts,high quality reservoir,fault seal ability and fault-sand matching style.That is to say,oil and gas accumulation parts are controlled by single 'fault terrace zone' high point,shallow water delta distributary channel and the river control sheet are high quality reservoirs,the lateral sealing ability of the fault affect hydrocarbon vertical enrichment height and plane 'complementary' characteristic,fault and single sand body matching style determine oil and gas enrichment position.