摘要
为了研究Toolebuc组页岩微观孔隙结构特征,应用有机地球化学、X-射线衍射对页岩矿物组分进行了测定,并通过氩离子抛光扫描电镜、液氮吸附及高压压汞等实验手段对页岩孔隙类型及孔隙结构进行了深入的分析。结果表明：Toolebuc组页岩为高丰度海相页岩,脆性矿物含量约为55%,具有一定的可压裂性;页岩平均孔隙度为15%,渗透率主要分布在（0.002～0.116）×10^-3μm^2之间;孔隙类型包括黏土矿物粒间孔、岩石骨架颗粒粒间孔、有机质孔隙、生物化石孔、有机酸溶孔及微裂缝6种类型,其中黏土矿物粒间孔、岩石骨架颗粒粒间孔最为发育;页岩孔径分布复杂,以中孔为主,其次为大孔和微孔;大孔及中孔提供了大部分孔体积,有利于游离气的聚集,中孔及微孔比表面积所占的比例最高,有利于吸附气的保存;页岩孔隙类型及分布受成岩演化及热演化的控制作用明显。
In order to investigate the nanostructure morphology of shale reservoirs of the Toolebuc Formation,organic geochemical and X-ray diffraction experiments are used to measure the mineral composition and argon ion polishing-SEM,liquid nitrogen adsorption and high pressure mercury experiments are used to analyze the pore types and structures of Toolebuc shale.Result shows that shale of Toolebuc Formation is high abundance marine shale,the content of brittle minerals is 55%,and can be fractured.The average porosity of shale is 15%,while the permeability ranges from 0.002×10^-3μm^2 to 0.116×10^-3μm^2.Research shows that pores of shale can be classified into six types：Inter-particle pores between clay minerals,mineral pores in rock skeletons,pores in organic,apertures in paleontology fossils,organic acid solution pores and micro-fractures,of which the most common ones are inter-particle pores between clay minerals and mineral pores in rock skeletons.The pores size distribution of shale is complex,which includes not only predominant mode-pores,but also a certain amount of macro-pores and micro-pores.Macro-pores and mode-pores provide most of pore volume,it is good for the accumulation of free gas,and mode-pores and micro-pores provide most of specific surface area,and it is good for the preservation of absorbed gas.The types and distribution of pores in shale are obviously controlled by the diagenetic evolution and thermal evolution.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2015年第5期979-985,共7页
Natural Gas Geoscience
基金
国家自然科学基金项目(编号:41272156)
中海油能源发展重大专项(编号:E-J613D002)联合资助
