萨中开发区葡Ⅰ组储层微观渗流特征研究

发布时间：2018-09-04 07:29

【摘要】：在油田进入高含水后期,因油水渗流、注入剂驱油、剩余油的形成与分布皆发生在储层内部,储层微观渗流特征对开发效果影响较大。因此,查明不同砂体微观渗流特征,对制定增产措施,有效挖潜剩余油具有重大的意义。本文在油气田储层地质学、油气田开发地质学和油层物理学等理论指导下,综合室内岩心分析资料及相渗曲线、驱替实验、核磁共振和CT扫描等室内实验结果,研究了不同孔隙结构类型的渗流特征:从Ⅰ类到Ⅴ类孔隙结构,小孔喉比例逐渐增加,有效渗流通过逐渐减少,驱油效率逐渐降低;在相渗曲线上,束缚水饱和度和残余油饱和度逐渐增加,两相渗流范围逐渐变窄;随孔隙结构类型变差,非均质性增强,孔喉分布变得不均匀,孔喉连通性变差,有效渗流通道减少,微观剩余油增多。研究了不同开发阶段、不同砂体内部微观渗流特征。在垂向上,河道砂体的平均含水饱和度与渗透率具有较好的正相关性,渗透率越高,含水饱和度越大。辫状河道、曲流河道总体含水饱和度高于其它类型砂体。砂体厚度、单砂体的垂向孔隙结构类型以及变异系数等参数对含水饱和度有直接影响;在平面上,不同相环境中,水淹部位高的均为孔隙结构类型相对好的区域。在不同时期,河道砂与非河砂均呈现出孔隙度、渗透率、含水饱和度增加的趋势。非河砂体各参数变化幅度较河道砂体更小。最后分析了微观渗流特征对采收率的影响,总体各砂体平均孔隙结构类型越好,微观剩余油越少;砂体厚度越大,上部驱替效果越不好;当变异系数增加时,可使注入水在垂向上分布更均匀。
[Abstract]:In the late stage of high water cut, the formation and distribution of remaining oil occurred in the reservoir because of oil-water seepage, injection agent flooding and residual oil distribution. The microcosmic percolation characteristics of reservoir have great influence on the development effect. Therefore, it is of great significance to find out the microscopic seepage characteristics of different sand bodies in order to draw up the measures for increasing production and effectively tap the remaining oil. Under the guidance of the theories of reservoir geology, development geology and reservoir physics of oil and gas fields, this paper synthesizes the laboratory data of core analysis and permeability curves, displacement experiments, nuclear magnetic resonance (NMR) and CT scanning, etc. The percolation characteristics of different pore structure types are studied: from class I to type V pore structure, the ratio of pore throat to pore throat increases gradually, the effective percolation decreases gradually, and the oil displacement efficiency decreases gradually. The irreducible water saturation and residual oil saturation increase gradually, and the two phase percolation range becomes narrower, with the pore structure type becoming worse, the heterogeneity increasing, the pore throat distribution becoming uneven, the pore throat connectivity becoming worse, and the effective seepage channel decreasing. The microscopic residual oil increased. The microscopic percolation characteristics of different sand bodies in different stages of development are studied. In vertical direction, the average water saturation of channel sand body has a good positive correlation with permeability. The higher the permeability, the greater the water saturation. The total water saturation of braided channel and meandering channel is higher than that of other types of sand bodies. The thickness of sand body, vertical pore structure type of single sand body and coefficient of variation have direct influence on water saturation. In different periods, both channel sand and non-river sand show an increasing trend of porosity, permeability and water saturation. The variation range of parameters of non-river sand body is smaller than that of channel sand body. Finally, the influence of microscopic seepage characteristics on recovery is analyzed. The better the average pore structure type of sand body is, the less residual oil is, the greater the thickness of sand body is, the worse the displacement effect of upper part is, and when the coefficient of variation increases, The injection water can be distributed more evenly in vertical direction.
【学位授予单位】：东北石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE312

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