S油藏产能评价及开发方式优化设计

S油藏属于复杂断块和局部异常高压油藏,在对其地质特征以及现有10口试油测试和试采井共23井次的测试资料系统分析基础上,运用层序地层学、试井边界探测分析、产能评价等多种油藏工程方法对S油藏P1、P2、P3组等3套含油层系的压力系统、原油性质、测试产能、米采油指数和采油强度等开发设计所需技术政策界限进行了评价,认为:P1组为一套正常压力系统、普通黑油为主、测试折算日产油能力在20 t左右、米采油指数较高的弹性水压驱动油藏;P2、P3组为异常高压、轻质挥发油为主、测试折算日产油在40～50 t左右、米采油指数较高的天然能量驱动油藏。结合S油藏地质条件,综合运用单井经济极限控制储量、经济极限井网密度、以及经济最佳井网密度等计算方法确定了S油藏合理井网密度和井距,运用复杂断块油藏建模及数值模拟方法对注水开采S区块P1油藏、天然能量间歇开采P2和P3油藏的开发方案进行了优化设计,提出最佳开发方案为部署直井14口井,水平井3口,预测15年后方案累产油93.48×104t,采出程度分别达到22.53%、8.19%和12.95%。

Productivity Evaluation and Optimization of Exploitation Methods of S Reservoir

The S reservoir located in the west coast of Africa is characterized by complex blocks and its local block has an abnormal high pressure.There is the need to optimize the reservoir’s exploitation program rationally.Based on S reservoir geological features and the test data analysis system of the existed 10 test wells and producing test wells of 23 wells,using sequence stratigraphy,well test analysis of the boundary detection,capacity evaluation and other reservoir engineering methods,we evaluated the exploitation policy limits of the pressure systems,crude oil properties,test production,per meter productivity index,the oil intensity of production and other design technologies of the S reservoir’s P1,P2,P3 group of its three oil-bearing strata.We concluded that P1 group is a set of normal pressure system,ordinary black oil-based,20 t or so for the test conversion daily oil production capacity,a flexible hydraulic drive reservoir of higher per meter productivity index.P2,P3 group are sets of abnormally high pressure system,light volatile oil-based,40～50 t or so for test converted oil production capacity,natural energy-drive reservoir of higher per meter productivity index.With S reservoir’s geological conditions,the integrated application of the controlling reserves of economic limit of single well,the density of the economic limit of wells and other calculation methods to determine S reservoir’s rational well spacing and density of well pattern.Applicing oil reservoir modeling and numerical simulation of complex fault-block,we optimized the exploitation programs of P1 reservoir of water flooding,and P2 and P3 reservoir of natural energy interval drive,and proposed the best exploitation program for the deployment of 14 vertical wells,3 horizontal wells.The accumulated oil production will have reached 93.48×104 t after 15 years according to this program,recovery percent will have reached 22.53%,8.19% and 12.95% respectively.