渤海湾盆地埕北低凸起A块东营组储层特征及水驱剩余油分布规律研究OA
Reservoir characteristics and distribution of water-flooded residual oil in the Dongying Formation of Block A,Chengbei Low Uplift,Bohai Bay Basin
埕北低凸起 A 块为渤海湾盆地的重点开发区块,自投入开发以来已实现一定规模的油气产量,但也存在储层特征不明确、水驱开发含水率上升快、剩余油分布不清晰等问题,严重影响该区油气的高效挖潜.本文利用地震、测井、录井、开发动态等资料,对 A 区块开展储层特征与水驱剩余油分布规律研究.研究结果表明,研究区主力含油层段东营组 9 砂组(Ed9)和 8 砂组(Ed8)储层为形成于深湖—半深湖相的浊积水道砂体,储层岩性主要为中细粒岩屑长石砂岩,储层主要为中孔中低渗储层,但非均质性异常突出.Ed8 储层主要发育于 6 小层(Ed86),Ed9 储层主要发育于 5 小层(Ed95),这些层段的砂体连片性较好,分布面积较大,呈现自 SW 向 NE 向减薄的变化特征.研究区开发阶段可划分为天然能量开发、强化注水、稀井网水驱和综合调整 4 个阶段,初期采用天然能量开发基本不出水,后续强化注水使得地层能量得以补充,但含水率上升快,特别是东部水淹严重.平面上,Ed9—Ed8 剩余油主要分布于研究区的西南部;纵向上,剩余油主要分布于 Ed86 1 号单砂体(Ed86-1)、Ed95 的 1 号单砂体(Ed95-1)和 2 号单砂体(Ed95-2).砂体厚度是剩余油分布的主要控制因素,砂体厚度大的区域具有较高的剩余油丰度;构造形态对剩余油分布也有很好的控制作用,区块南部因处于构造高位往往具有较高的剩余油丰度.研究结果可对该区调整开发方案、提高采收率等提供依据,更可为渤海湾盆地同类油气藏的开发提供参考.
Block A of Chengbei Low Uplift is a key development block in the Bohai Bay Basin.Since its com-mencement of production,it has achieved a considerable scale of oil and gas output.However,challenges such as unclear reservoir characteristics,rapid water-cut rise in water-cut development,and ambiguous distribution of re-sidual oil,which seriously hindered the efficient exploitation of oil and gas in this area.By combining seismic,logging,coring,and dynamic development performance,the reservoir characteristics and water-driven residual oil distribution law in Block A were studied.Results show that the reservoirs of the 9th sand unit(Ed9)and the 8th sand unit(Ed8)of the Dongying Formation,the main oil-bearing units in the study area,are turbidite channel sand bodies of deep lake-semi-deep lake facies.The reservoir lithology is mainly medium-fine-grained lithic arkose,with mainly medium-porosity,medium-low permeability,and high heterogeneity.The Ed8 reservoir was mainly developed in the 6th subunit(Ed86),and the Ed9 reservoir is mainly developed in the 5th subunit(Ed95).These sandbodies have good continuity,distribute widely,and thin out from southwest to northeast.The development of the study area can be divided into four stages:natural energy development,enhanced water injection,sparse-well water-driving,and overall adjustment.In the first stage,natural energy was produced with largely no water;sub-sequent enhanced water injection supplemented the energy build-up in the reservoir but became watery rapidly,resulting in serious water flooding in the eastern wells.Horizontally,the residual oil in Ed9-Ed8 is mainly distrib-uted in the southwest of the study area;and vertically,the residual oil is mainly distributed in the 1st single sand-body unit of Ed8(Ed86-1),the 1st single sandbody unit of Ed95(Ed95-1)and the 2nd single sandbody unit of Ed95(Ed95-2).The sandbody thickness is the main factor on the distribution of residual oil,while the areas with thick sandbody tend to be rich in residual oil.The structural shape played a role in controlling the distribution of the re-sidual oil.The southern part of the production block often has a higher residual-oil abundance due to its high structural position.This study provided a basis for adjusting the development plan and improving the recovery rate in this area as a valuable reference for the development of similar oil and gas reservoirs in the Bohai Bay Basin.
黄文欢
中石化胜利油田鲁胜石油开发有限责任公司,东营 257077||中国地质大学(北京)能源学院,北京 100083
海洋科学
储层预测剩余油分布规律数值建模埕北低凸起渤海湾盆地
reservoir predictiondistribution law of residual oilnumerical modelingChengbei Low UpliftBo-hai Bay Basin
《海洋地质前沿》 2026 (6)
38-50,13
国家科技重大专项重点项目"先导试验区提高水驱采收率应用研究"(2011ZX05011-003)
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