页岩油储层评价指标体系

Evaluation index system of shale oil reservoirs

页岩油是我国继致密油、页岩气成功开发后下一个重点突破的非常规油气勘探开发目标。页岩油有广义与狭义之分,其分类与评价方案繁多。本文采用广义的页岩油储层的概念,着眼于国内与国外对页岩油评价的不同思路,以及页岩油储层与烃源岩评价指标的异同,论述了国内重点关注的"五度"(储层深度、储层厚度、有机质丰度、有机质成熟度、脆性度)指标及页岩基础物性参数(孔隙度、渗透率、孔喉直径),并引入北美页岩油流体性质风险评估的6个指标(OSI、AI、POI、GOR、碳酸盐含量、总含油量)。结合我国页岩地质地球化学特征,参考北美页岩油储层实例,系统论述了影响页岩油资源潜力与可采性的主要评价指标,并给出了优选区、有利区、风险区的流体参数值范围,以期对我国页岩油勘探开发提供理论指导。

Following the successful development of shale gas and tight oil, shale oil is now becoming the next target of unconventional oil and gas. The definition of shale oil includes a broad sense and a narrow sense, with a wide variety of classifications and evaluation criteria. The present paper accepts the broad definition from the view of the shale system. Focusing on the different ideas to evaluate shale oil adopted domestically and overseas, and the similarities and differences of assessment between source rocks and shale oil reservoirs, the five geological parameters which are focused on by Chinese scholars （shale depth, reservoir thickness, TOC, Ro and brittle strength） and three shale physical property indicators （porosity, permeability and pore throat size distribution） are fully described. Six parameters （OSI, AI, POI, GOR, carbonate content and total oil） to characterize fluid properties for shale oil risk assessment applied widely in North America are further suggested. In combination with the geological and geochemical characteristics of Chinese shales, through citing the examples of some shale oil reservoirs in North America, the factors to impact the shale oil resource potential and recoverability are discussed, and the range of the main fluid criteria for an optimization area, favorable area and risk area is given. This work is expected to provide a theoretical guidance for shale oil exploration and development in China.