缝洞型油藏高压注水关键地质因素剖析

Analysis of Key Geological Factors of High Pressure Water Injection in Fractured Reservoir

摘要: 对于缝洞油藏的开发，高压注水是一种较为有效的开发方式。本文通过建立不同地质特征的高压注水机理模型，采用数值模拟的方法，系统的剖析了两种关键地质控制因素(储集体之间的分布位置、裂缝部位)对高压注水效果的影响；并与常规注水效果进行对比，以此来指导缝洞型碳酸盐岩高压注水地质条件的选择，根据模拟结果可知，当两套储集体分布为侧上分布时，高压注水无效；第二套储集体越接近第一套储集体下部，高压注水效果越好。当两套储集体为水平分布时，裂缝的位置对高压注水效果有影响。当裂缝处于高部位和低部位时，高压注水效果一般；当裂缝处于中部位时，高压注水效果较好。

Abstract: High-pressure water injection is an effective way to develop fractured-vuggy carbonate reservoirs. By establishing the mechanism model of high-pressure water injection with different geological characteristics and adopting the method of numerical simulation, this paper systematically analyzes the influence of two key geological control factors (the distribution position between reservoir groups and fracture location) on the effect of high-pressure water injection. The results are compared with those of conventional water injection to provide guidance on how to locate the geology of high-pressure water injection in fractured-vuggy carbonate rocks. According to the simulation results, the high-pressure water injection is invalid when the two reservoirs are distributed on the upper side. The closer the second reservoir is to the lower part of the first reservoir, the better the effect of high-pressure water injection will have. And when the two reservoirs are distributed horizontally, the position of fractures has an impact on high-pressure water injection. When the fracture is in the high and low position, high-pressure water injection gets little effect. When the fracture is in the middle position, the effect of high-pressure water injection is better.