利用单渗砂层优势微相带分析温西三块储层水淹层剩余油分布

Using Concept of Single Permeability Sand Layer Favorable Microfacies Belt to Analysis Remaining Oil Distribution in Wenxisan Block Water Flooded Reservoir

针对温西三块三间房组辫状河三角洲前缘储集砂体在注水开发中砂体结构、赋存状态及剩余油分布复杂特点,提出利用单渗砂层优势微相带概念评价有利沉积微相及其剩余油分布的方法。通过目的层段单渗砂层能量厚度及其岩性、物性和自然电位减小系数、自然伽马减小系数、声波时差、密度、中子孔隙度、深侧向、深感应电阻率建立精细评价有利沉积微相的单渗砂层能量厚度标准,准确提取单渗砂层优势微相带沉积能量及其测井参数信息,有效地展示出目的层段单渗砂层能量厚度垂向演化的水下分流河道、河口坝、席状砂、远砂微相平面展布规模和范围,并列举出注水开发中主体微相河道正向叠置韵律层中的层间差异层和非主体微相席状砂层受河道高渗层间干扰造成的剩余油分布层段,为准确预测和筛选不同类型已动用油层及未动用(或基本未动用)油层剩余油分布提供了可靠地质依据。

In view of the dual function of river water and lake wave at Wenxisan block Sanjianfang formation braided river delta front reservoir sand, and the characteristics of sand structure, occurrence condition and complex remaining oil distribution in the waterflood development, we use the concept of single permeability sand layer favorable microfacies belt to refinedly evaluate favorable sedimentary microfacies and remaining oil distribution. In this paper, with favorable single permeability sand microfacies belt concept and through the single permeability sand layer thickness, self-potential decrease coefficient, natural gamma ray decrease coefficient, acoustic interval, density, neutron porosity, deep lateral, deep induction resistivity and lithology, porosity, permeability of objective strata. We have set up single permeability sand layer energy thickness refined evaluation standard of favorable sedimentary microfaeies, accurately extracted single permeability sand favorable sedimentary microfacies belt sedimentary energy and logging parameter information. So effectively showing the plane distribution scale and scope of single permeability sand layer energy thickness vertical evolution underwater distributary channel, mouth bar, sheet sand, distal sand microfacies at the objective strata, and citing that in thewaterflood development the strata remaining oil distribution is caused by differential layers in main microfacies river channel positive superimposed rhythmite and non-subject microfacies sheet sand layer disturbed by river channel high permeability layer. The above result is a reliable geological basis to accurately predict and filtrate remaining oil distribution in different types of used and unused （or basically unused） reservoirs.