湘鄂西地区志留系龙马溪组页岩微观孔隙结构特征及定量表征  

Micro-pore structure characteristics and quantitative characterization of Silurian Longmaxi shale in western Hubei and Hunan areas

作　　者：徐洁 郭维华[4] 刘皓天[5] 秦臻[1,3] 孟强 陶辉飞 XU Jie;GUO Wei-hua;LIU Hao-tian;QIN Zhen;MENG Qiang;TAO Hui-fei(Key Laboratory of Petroleum Resources,Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences,Lanzhou 730000,China;Peili Petroleum Engineering College,Lanzhou City University,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Research Institute of Petroleum Exploration&Development?Northwest,PetroChina,Lanzhou 730000,China;Exploration and Development Research Institute,SINOPEC,Jianghan Oilfield Company,Wuhan 430000,China)

机构地区：[1]中国科学院西北生态环境资源研究院甘肃省油气资源研究重点实验室,甘肃兰州730000 [2]兰州城市学院培黎石油工程学院,甘肃兰州730000 [3]中国科学院大学,北京100049 [4]中国石油勘探开发研究院西北分院,甘肃兰州730000 [5]中国石化江汉油田分公司勘探开发研究院,湖北武汉430000

出　　处：《天然气地球科学》2021年第4期611-622,共12页Natural Gas Geoscience

基　　金：甘肃省自然科学基金(编号:18JR3RA396);国家自然科学基金(编号:41903013);中国科学院“西部之光”项目联合资助。

摘　　要：湘鄂西地区为南方海相页岩气勘探开发潜力区之一,志留系龙马溪组是其有利的页岩气层段。利用氩离子抛光—扫描电镜、低温低压氮气和二氧化碳吸附等实验对该区4口取心井的页岩样品孔隙结构进行了定性和定量的联合表征。实验结果表明:该区页岩发育有粒间孔、粒内孔、有机孔、有机质—黏土矿物复合孔以及解理缝,其中最为发育的是黏土矿物与自生矿物相间的粒间孔、有机质—黏土矿物复合孔以及有机孔。页岩样品比表面积为8.038~24.552 m^(2)/g,平均为13.769 m^(2)/g,BJH孔径中孔直径为8.21~13.79 nm,平均为10.43 nm,其中LY1井孔径最大为11 nm,是该井有构造缝发育所致。The western Hubei and Hunan areas are one of the potential areas for marine shale gas exploration and development in the south,while the Lower Silurian Longmaxi Formation is one of the favorable shale gas intervals.In this study,the pore structures of shale samples from four coring wells in this area were characterized qualitatively and quantitatively by FE-SEM,low-temperature and low-pressure N2 and CO2 isothermal adsorption experiments.The experimental results show that there are abundant of interparticle pores,intraparticle pores,organic pores,compound pores of organic-clay minerals,as well as cleavage cracks in the shale,among which the most developed are interparticle pores of clay minerals and autogenous minerals,compound pores of organic-clay minerals and organic pores.The specific surface area of the shale is from 8.038 m^(2)/g to 24.552 m^(2)/g,with an average of 13.769 m^(2)/g.The median diameter of the BJH pore diameter is from 8.21 nm to 13.79 nm,with an average of 10.43 nm.The largest pore diameter of Well LY1 is 11 nm,which is caused by the development of structural fractures in the well.

关 键 词：湘鄂西 龙马溪组 孔隙结构 低温低压氮气吸附 低温低压二氧化碳吸附 

分 类 号：TE132.2[石油与天然气工程—油气勘探]