火山岩裂缝型储层应力敏感性实验研究

准噶尔盆地火山岩油气藏埋藏深、岩石类型复杂、裂缝较为发育,属于典型的裂缝型储层。为研究火山岩气藏开发过程中储层的物性变化规律,弄清裂缝的产状与应力敏感性之间的相互关系,从不同火山岩岩性的岩心图像入手,通过对岩心裂缝进行可视化描述,在弄清裂缝发育特征和产状的基础上,对研究区内5口丼20多块岩心样品进行渗透率应力敏感性实验研究和分析。通过对不同裂缝产状的岩心应力敏感性实验研究可知,火山岩储层的应力敏感性不仅与裂缝的发育程度有关,而且与裂缝的产状紧密相关。低角度缝较发育的具有网状缝系统岩心的应力敏感性最强,高角度缝岩心的次之,直劈缝岩心的则相对较弱。

Experiment of Stress Sensitivity for Igneous Fractured Reservoir

Volcanic oil and gas reservoir in the Junggar basin is characterized as deep buried,complex rock types,and fractures,so it is a typical of fracture reservoir.In order to understand the variation of reservoir properties during volcanic gas reservoir development process and illustrate relationship between fracture occurrence and stress sensitivity,we visually describe the features and occurrences of fractures in the volcanic cores,and do experiments of permeability and stress sensitivity for 20 core samples of 5 wells.The experimental results show that the stress sensitivity of volcanic reservoirs not only depends on fracture sizes but also are related to fractures occurrence.Stress sensitivity of net fracture system with low-angle fractures is the strongest one,followed by high-angle;and the stress sensitivity of vertical-angle fractures is relatively weak.