低渗透油藏井网优化技术研究-以河135断块区为例

A study on well pattern optimization technique in the low-permeable oil reservoir-taking He 135 fault block as an example

谭光明

Tan Guangming

中国石化胜利油田有限公司现河采油厂, 山东东营 257068

Xianhe Oil Production Plant of Shengli Oil Field Co.Ltd, SINOPEC, Dongying 257068

低渗透油藏受特殊的成藏条件、沉积环境影响, 具有孔隙结构复杂、孔喉半径细小, 油藏渗透率低, 一般小于50×10-3μm2;储层非均质严重, 平面渗透率级差最高达几百个数量级;驱替压力大、存在一定的启动压力;天然裂缝发育且存在人工裂缝等特点;因此, 在不同渗透率级差下, 如何建立起有效的驱替半径, 建立合理、经济的井网密度, 对提高低渗油藏水驱油效率及采收率, 提高低渗透油藏的开发水平具有十分重要的意义。以低渗透油藏河135断块区为例, 通过系统地对河135断块区储层非均质、裂缝进行研究, 建立储层非均质-裂缝模型, 在地质研究的基础上, 针对不同渗透率级别、不同沉积相带, 确定了不同的技术极限井距及经济合理井距, 并考虑裂缝推出了适合的井网形式。

Under the influences of peculiar reservoir-forming condition and sedimentary environment, the low-permeable oil reservoir has some characteristics, such as the complicated spore configuration, the exiguous pore throat, the low permeability, generally less than 100×10-3μm2, the serious reservoir heterogeneity, the plane permeability varies greatly, the big displacement pressure, existing certain starting pressure, natural fracture growth and existing man-made fracture, etc. Therefore how to establish the effective displacement radius, and the reasonable and economic well density with different permeability, it's important to raise the oil-water displacement efficiency, recovery efficiency factor and exploitation level of the low-permeable oil reservoir. This paper takes the He 135 fault block as an example, studies systematically reservoir heterogeneity and crack of the He 135 block, and founds the reservoir heterogeneity-crack model. Based on the geological study, conform the different technical limited well spacing and economic and reasonable well spacing with different permeability and sedimentary microfacies, and proposing the befitting pattern considering crack.