金湖凹陷阜宁组砂岩储层敏感性分析

Analysis of Sensitivities for Sandstone Reservoir, Funing Formation in Jinhu Depression

The velocity sensitivity of a sandstone reservoir, Funing formation in Jinhu depression, situated in Jiangsu province, is related to the degree of rock consolidation and to the type, content and attitute of clay minerals, and its water sensitivity concerned mainly to the content of montmorillonite, the content and attitute of other clay minerals. The acid sensitivity(HCI) is relevant to carbonate filling in and iron minerals. It is shown by experiments that there are more intensive velocity sensitivity and water sensitivity in the third member of Funing formation in Jinhu depression and acid and water sensitivity in the second and the frist members. From this, proposals are presented: a) to put clay-stabilizer into injection water or to increase the salinity of injection water in order to decrease or eliminate the water sensitivity; b) to prevent oxidant or air from entering into a well or add a certain amount of reductant for limiting the pH value of the return acid solution or Fe~(3+)complexing agents in order to decrease or eliminate the acid sensitivity.