济阳坳陷碎屑岩储层胶结指数变化规律分析

Analysis of cementation exponent of the clastic rock reservoirs in the Jiyang Depression

胶结指数m是储层固结特征、孔隙结构特征及黏土矿物等地质因素的综合反映。济阳坳陷不同成岩带碎屑岩的储层岩电实验结果表明,次生孔隙的存在导致m值减小,泥质附加导电作用对泥质储层m值的影响受地层水矿化度大小的控制。固结程度好的储层,m值趋于稳定。深成岩带m值接近2,超深成岩带受次生子孔隙发育的影响,m值趋于减小。中、浅成岩带由于岩石固结程度差,储层性质复杂,m值的变化范围大,总体上反映出复杂孔隙结构特征的高值。

Core electricity experiments of the clastic rock reservoirs in different diagenetic zones of the Jiyang Depression indicate that the cementation exponent m is a comprehensive reflection of the geological factors such as reservoir cementation,pore structure and clay minerals.The existence of secondary porosity leads to a smaller m value,and the influence of additional electric conductivity of clay on the m value of argillaceous reservoir is subject to the size of formation water salinity.The well cemented reservoirs tend to have a stable m value.The m value of deep diagenetic zone is about 2,while secondary porosity had affected the ultra-deep diagenetic zone leading to a decrease of m value.The m value changes greatly in the middle and shallow diagenetic zones due to poor rock cementation and complex reservoir properties,generally showing features of complex pore structure.