缝洞型碳酸盐岩油藏注水替油井水驱特征曲线多样性与生产动态关系

Relation between water-drive curve multiplicity and production performance for water injection-production well of fractured-vuggy carbonate oil reservoir

以塔河油田奥陶系油藏注水替油井为例,研究发现缝洞型碳酸盐岩油藏注水替油井水驱曲线形态主要受外部注入水量影响,其水驱曲线具有多样性包括直角阶梯型、快速上升不规则型、多直线段型以及复合型;利用水驱曲线拐点可以简易识别注水轮次,垂直直线段长短表明注水焖井结束开井之初含水突升幅度大小,而水平直线段的长短表明含水回落后底水稳产持续时间的长短;水驱曲线四种形态分别对应生产动态的低含水稳产型、含水暴性水淹型、含水高—低波动型以及含水阶段上升型。最后提出油井的储层类型与缝洞及油水空间配置关系会直接影响到单井注水替油效果,而注水替油技术在钻井放空漏失井、定容特征明显的井及油井位于封闭缝洞体局部高点时能够得以高效开展。

Taking carbonate reservoir in Tahe oilfield as an example, the study found that the water drive curves for water injectionproduction wells in fractured-vuggy carbonate reservoir are affected by injected water. Besides, the curves are multiple, including right-angle-step shape, irregular shape, multiple straight line segments shape and complex shape. In addition, the cyclic times of water injection can be recognized easily, e. g. the length of vertical line segments shows the increasing range of water cut at the beginning of production after soak stage, while the length of horizontal line segments shows the length of continuous time when producing stably after water cut falling. Finally, the reservoir type of wells and fractured-vuggy and water/oil space directly influence the water injection for oil effects of single well are proposed. However, water injection for oil technique can be carried out efficiently for wells with leakage, significant volume characteristics and high position.