研究页岩油气资源分级评价标准,以准确评价页岩油气资源潜力。对松辽、海拉尔、济阳等5个地区烃源岩层地球化学指标进行统计分析,利用烃源岩含油量与TOC关系的"三分性",按富集程度将页岩油气分为分散(无效)资源、低效资源和富集资源3级;有机质大量生油/气的成熟阶段对应富集页岩油/气窗,页岩油气资源级别按TOC值划分。结合页岩中脆性矿物的含量、页岩(层系)的厚度、埋深等,定义评价页岩油气可采性的可采性指数并建立其计算公式,以定量评价页岩油气的可采性。实际应用中,根据用TOC-测井响应相关性确定的井剖面上的TOC值变化,可以得到不同级别页岩的等厚图及分级页岩油气资源量;再结合分级标准,利用TOC等值线和Ro等值线的叠合,可识别有利的页岩油气区。
Research on the evaluation criteria of shale oil/gas is conducted so as to accurately assess the resources potential of shale oil and gas.After making statistic analysis of the geochemical index of hydrocarbon source rock layers in five areas such as Songliao,Hailaer,Jiyang,based on the characteristic of triple-division between the oil content and TOC of source rock,this paper classifies shale oil/gas into three levels of resources in terms of enrichment degree: scattered(ineffective) resources,low efficient resources and enriched resources.The mature stage,at which organic matter generates oil/gas in large amounts,corresponds to shale oil/gas enrichment window.Furthermore,recoverable index is defined and its computation formula is proposed to provide a quantitative index for recoverability evaluation,considering the brittle mineral content,thickness and depth of shale,etc.In practice,TOC variable values in well profile obtained by TOC-logging correspondence can be used to draw the TOC isopach map and calculate the resources amount of different levels.Then combined with the evaluation criteria,TOC and Roisopach maps are superimposed to identify the favorable shale oil/gas areas.