夹层对不同韵律底水油藏开发效果的影响机理——以苏丹H油田为例

以苏丹块状底水油藏H油田为原型,运用数值模拟方法建立了正韵律、反韵律、复合正韵律和复合反韵律底水油藏的数值模型,研究了不同夹层半径、厚度及分布条件下各种韵律油藏的开发效果,并提出了相应的开发技术对策。结果表明,对不同韵律底水油藏,含夹层油藏的开发效果均得到不同程度的改善,控水效果随着夹层半径的增大而变好;夹层厚度对开发效果影响不大,低含水期正韵律底水油藏和中高含水期反韵律底水油藏控水效果相对较好;夹层分布在距离油水界面较近或存在多夹层情况下开发效果好;剩余油主要分布在夹层之间和夹层下部。不同韵律底水油藏的开发策略主要为充分利用隔夹层优化射孔,结合垂向与水平渗透率之比控制采油速度和适时实施人工夹层等减缓底水锥进速度。H油田开发实践表明,充分利用隔夹层优化射孔并部署加密水平井能取得较好的开发效果。

Mechanism study on effect of inter-bed on development performance of different rhythm bottom-water reservoir-taking Sudan H oilfield as example

Taking bottom water H oilfield in Sudan for example, various rhythm bottom-water reservoir numerical models are established, and the effect of inter-bed size, height and location on development performance is studied, and the technology strategy is pointed out herein. The result shows that the inter-bed is helpful to improve the development performance, and the effect of water cut control is improved with the increment of inter-bed radius; and the height of inter-bed has a few effect on development performance; and the good water cut control effect is obtained in positive rhythm reservoir during low water-cut stage and in reverse rhythm during high water water-cut stage; the inter-bed located on the area near the water-oil-contact and multi-inter-bed in bottom-water reservoir show great performance; and the remaining oil is mainly located on the area between and under the inter-bed. The development technique strategy of various rhythm bottom-water reservoirs for controlling water coning is proposed, such as the perforation optimization by making full use of inter-bed, off-take rate optimization by controlling vertical-horizontal permeability ratio, and artificial inter-bed implementation and so on. The development practice of H oilfield shows great performance using optimization completion technique after making full use of inter-bed and deploying horizontal well.