长期注水开发油藏的孔隙结构变化规律

应用水驱油实验和岩心分析资料，研究东营凹陷胜坨油田二区沙二段8^3层三角洲前缘相储集层的孔隙结构随注水开发而发生变化的规律。孔隙特征明显变好，表现为孔隙形状因子变大，形状变得比较规整、平滑，颗粒磨圆度变好，平均比表面变小，孔隙连通性交好，均质程度增高。喉道特征变化复杂，总体上喉道半径有增大的趋势，分选性变好，喉道连通性和控流性变化复杂，孔渗性较低的储集层喉道非均质程度增强。图2表3参11

Law of pore structure variety in reservoir during a long episode waterflooded development

Applying waterflooding experiment and core analytical data, the authors studied the law of pore structure variety in delta reservoir during a long episode waterflood development, that is in layer of 8 3 in second member of Shahejie formation (in age of Neogene) in Shengtuo oilfield of Shegnli region. The character of pore is obviously changed for a better condition after the water flooded development. Shape factor of pore is fleshed out, the shape of pore is changed to more regular and smooth; the average specific surface of pore is diminished; the pore connectivity is alter for the better; and the isotrope degree is increment. The variety law of pore throat is complex. The radius of throat trends to aggrandize; sorting coefficient incline to decrease. The connectivity of pore throat has complex varying law, heterogeneity of pore throat in lower permeability trend to be buildup while homogeneity incline to boost up.