长深气田火成岩储层应力敏感性及其成因机理

Pressure Sensitivity and Its Genetic Mechanism of Igneous Rock Formations in Changshen Gas Field

对吉林油田长深井区火成岩低孔低渗型储层取岩芯样品进行应力敏感性测试,样品的渗透率恢复率不超过11%,呈现极强的应力敏感性。通过储层岩芯观察及其他地区火成岩应力敏感性分析结果对比,认为火成岩储层应力敏感性与储层的岩性、结构、构造和孔隙、裂缝发育程度以及发育类型有关。与砂岩较单一的成岩作用不同,火成岩复杂的成岩作用导致不同地区火成岩储层应力敏感性不同,即便在同一地区,不同火成岩岩性储层的敏感性都可能不同。所以对火成岩储层应力敏感性评价应区别对待,不能一概而论。

The core samples of igneous rock formations with low permeability and low porosity in Jilin Changshen well block are tested for their pressure sensitivity.The result shows that permeability recovery rate of these samples is not more than 11%,which indicates high pressure sensitivity of the formations.By observing core samples and comparing the result of pressure sensitivity tests with those from igneous rock core samples of other regions,it shows that the pressure sensitivity of igneous rock formations is relevant to lithology,structure,construction,development and type of porosity and fracture.Different from the unitary diagenesis of sandstone,the complex diagenesis of igneous rock leads to different pressure sensitivity in different areas.Therefore the pressure sensitivity of different igneous rock formations should be treated differently.Meanwhile,pressure sensitivity of a certain well may not be the same in different igneous layers.