特低渗透油气藏成岩储集相的定量评价方法

An quantitative assessment method of the diagenetic reservoir facies in extra-low permeability oil-gas reservoir

针对陕北斜坡东部特低渗透储层受沉积作用和成岩作用两大因素控制的特点,利用灰色系统理论对成岩储集相进行了研究。分析了成岩作用综合效应及其相应的视压实率、视胶结率、视微孔率、成岩综合系数等定量指标和岩心分析数据,建立了成岩储集相综合评价参数、指标和分析方法。通过在安塞油田低孔隙度特低渗透长61油藏储层的实际应用,对目的层段开展了Ⅰ,Ⅱ,Ⅲ和Ⅳ类成岩储集相的定量评价和油气富集描述,有机地集成和综合了多种信息,实现了成岩储集相对沉积学、岩石学和成岩作用等特征的综合表征,并划分出有利成岩储集相区域,为指导油田有利含油区块的筛选和开发决策提供了重要依据。

The extra-low permeability reservoir in the east of Shanbei slope was controlled by two big factors of sedimentation and diagenesis. Using gray system theory studied the diagenetic reservoir facies in this area. The synthesized effects of diagenesis and its corresponding quantitative indexes such as apparent-compaction percentage, apparent cementation exponent, apparent microporous factor, diagenetic synthetical coefficient and related data of core analyses were analyzed. Comprehensive evaluation parameters,indexes and analytic method of the diagenetic reservoir facies were established. It was applied to low porosity, extra - low permeability Chang61 reservoir layers of AS oilfield. Ⅰ , Ⅱ , Ⅲ , Ⅳ type diagenetic reservoir facies were quantitatively evaluated and hydrocarbon enrichment was described in the target intervals. The synthesized characterization of the features of sedimentology, petrology, diagenesis by diagenetic reservoir facies was realized based on the organically intergrated and synthesized information. Regions and location of favorable diagenetic reservoir facies were compartmentalized and pointed out, which provided important foundation for the favorable oil- bearing block screening and development decision making in oil field.