四川盆地二叠系龙潭组页岩气储层特征与勘探潜力

Characteristics and Exploration Potential of Permian Longtan Formation Shale Gas Reservoir in Sichuan Basin

通过宏观野外实测、岩芯观察以及微观薄片鉴定、氩离子抛光扫描电镜观察(SEM)等技术手段,对四川盆地上二叠系龙潭组页岩气的储层特征进行了系统分析。龙潭期主要沉积环境从南向北依次发育:河流三角洲、滨岸沼泽、潮坪、混积陆棚与碳酸盐岩台地相。富有机质泥页岩主要发育在滨岸沼泽与深水陆棚相区,川北深水陆棚相页岩具有“四高一低”的特征:高含气量(>5 m^(3)/t)、高TOC(>4%)、高孔隙度(>6%)与低黏土矿物(<38%),是未来勘探的重点区。

A systematic analysis was conducted on the reservoir characteristics of shale gas in the Longtan formation of the Permian in Sichuan basin through macroscopic field measurements,core observation,microscopic thin section identification,and argon ion polishing scanning electron microscopy(SEM)observation.The main sedimentary environment of the Longtan period developed from south to north in sequence:river delta,coastal swamp,tidal flat,mixed continental shelf,and carbonate platform facies.Organic-rich shale is mainly developed in coastal swamps and deep-water shelf facies areas.The deep-water shelf facies shale in northern Sichuan has the characteristics of"four highs and one low":high gas content(>5 m^(3)/t)High TOC(>4%),high porosity(>6%),and low clay minerals(<38%)are key areas for future exploration.