湖相细粒沉积及其页岩气意义——以下寺湾柳洛峪区块长7油页岩为例  

Lacustrine Fine Grain Deposition and Its Significance to Shale Gas——A Case Study of Chang7 Reservoir in Yanchang Formation,Liuluoyu Block,Xiasiwan Area

作　　者：赵习森 郭峰[2] 石立华 党海龙 

机构地区：[1]陕西延长石油(集团)有限责任公司研究院,陕西西安710075 [2]西安石油大学地球科学与工程学院,陕西西安710065

出　　处：《非常规油气》2015年第5期1-6,共6页Unconventional Oil & Gas

基　　金：国家自然科学基金(41002043);陕西省教育厅重点科研计划项目(41302076)资助

摘　　要：湖相细粒沉积的研究对于页岩油气的勘探开发具有重要意义。以鄂尔多斯盆地下寺湾柳洛峪延长组长7油层组细粒沉积岩系为研究对象,在大量实验数据分析、单井岩心观察和测井微相分析的基础上,阐明了柳洛峪长7油层组沉积微相的发育特征,对陆相页岩气勘探前景进行了初步探讨。研究表明,下寺湾地区柳洛峪长7油层组主要发育三角洲—深湖—半深湖相沉积,页岩储层孔隙度范围为0.1%~13.14%,基质渗透率范围为0.003~1.49mD,总体为低孔隙度、低渗透率的特征。页岩有机质类型以Ⅰ型为主,其次为Ⅱ型,有机碳含量为0.51%~22.6%,镜质组反射率为0.7%~1.2%,处于成熟—高成熟演化阶段,具备页岩气生成的物质基础。泥页岩脆性矿物质量分数大于25%,有利于储层的后期改造。长7油层组泥页岩埋深适中,分布稳定,具有较好的勘探开发潜力。Abstract： Lacustrine fine grain deposition research is of great significance for shale oil and gas Exploration and develop- ment. Taking fine sedimentary rocks of Chang7 reservoir in Yanchang Formation of Liuluoyu Block in Xiasiwan Area of Or- dos Basin as research object, on the basis of a large number of experimental data, single-well core observation and logging microfacies analysis, we illuminated the development characters of sedimentary microfacies in the reservoir and preliminari- ly discussed the prospect of exploration for continental shale gas.. The results showed that the main facies in Chang7 reser- voir were delta-deep lake-half deep lake facies, the porosity of shale reservoir ranged from 0. 1% to 13.14%, and the ma- trix permeability was between 0. 003mD and 1.49mD. It featured in low porosity and low permeability in general. The organic matter was dominated by Type I and followed by Type II. TOC was 0. 51% N22.6%, and Ro was 0.7% ～ 1.2%. The reservoir was at the stage of maturation and high-maturation. It laid material basis for shale gas generation. The brittle mineral accounted for more than 25%, which was beneficial to the later reconstruction in reservoir. The buried depth of Chang7 reservoir was moderate with stable distribution. It pos- sessed huge potential for exploration and development.

关 键 词：湖相细粒沉积 下寺湾柳洛峪 长7 沉积特征 页岩气 

分 类 号：P618.13[天文地球—矿床学]