南泥湾油田XY油区注水开发中后期控水稳产方法探索
2020-10-21王群华樊平天呼园平黄博段景涛刘浪
王群华 樊平天 呼园平 黄博 段景涛 刘浪

摘 要:南泥湾油田XY油区储层天然裂缝发育,非均質性强,注水开发中后期油区水窜情况严重,严重影响了注水开发效率。本文提出的一种自适应深部调控技术可有效控制裂缝性窜流,有望为该油区稳油控水提供有力技术支撑。
关键词:XY油区;裂缝性;水窜;调驱
Abstract:In the XY oil area of the Nanniwan oil field, natural fractures in the reservoir are developed, and the heterogeneity is strong. The water channeling situation in the oil area during the middle and late stages of water injection development is serious, which seriously affects the efficiency of water injection development. An adaptive deep control technique proposed in this paper can effectively control fractured channeling flow, and is expected to provide strong technical support for oil stabilization and water control in this oil region.
Keywords:XY oil area;fracture;water channeling;profile control and water blocking
1 地质特征
南泥湾油田XY油区位于延安市南泥湾镇境内,地质构上位于鄂尔多斯盆地二级构造单元陕北斜坡中部[1]。油区主力开发层位为三叠系延长组长4+5及长6油层,沉积环境为三角洲平原沉积,物源方向为近北东--南西向,为典型水下分流河道沉积模式[2,3]。
①构造特征:XY油区地质构造整体上为一西倾单斜,地层倾角较小,局部发育微小型构造;
②岩石学特征:该区储层岩性以灰色细粒长石砂岩为主,碎屑岩颗粒沉积磨圆好、成熟度高;填隙物以方解石和黏土矿物居多;
③储层物性特征:该区长4+5储层孔隙度集中分布于0.037-0.21,渗透率最大值15mD,最小值0.1mD,平均值为1.6mD平均渗透率为0.71mD;长6储层孔隙度集中分布于0.06-0.12,渗透率主要分布于0.01mD-19mD,属于低孔隙度、超低渗透率的非常规油藏;
④压力梯度为0.84MPa/100m,属于低压系统。
2 储层非均质性
①层间非均质性:该区长6油层分层系数为2.04-3.43,砂体呈局部连通,连同方向与物源沉积方向相近;
②层内分均质性:该区层内渗透率极差范围在48-120之间,突进系数接近于9,变异系数趋近于1,层内渗流分均质性较严重[4];
③平面非均质性:受沉积环境及隔夹层发育影响该区平面非均质性较为严重;……p>
