从页岩到页岩气储层:论泥(页)岩层构成油气储集层的必要条件  

From shale to shale gas reservoir:On the necessary conditions for a shale layer to form an oil or gas reservoir

作　　者：周文[1,2] 蒋柯 徐浩[1] 周秋媚[1] 胡钦红 刘瑞崟 ZHOU Wen;JIANG Ke;XU Hao;ZHOU Qiumei;HU Qinhong;LIU Ruiyin(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;College of Energy(College of Modern Shale Gas Industry),Chengdu University of Technology,Chengdu 610059,China;School of Geoscience,China University of Petroleum(East China),Qingdao 266580,China;Guizhou Engineering Research Institute of Oil&Gas Exploration and Development,Guiyang 550081,China)

机构地区：[1]油气藏地质及开发工程全国重点实验室(成都理工大学),成都610059 [2]成都理工大学能源学院(页岩气现代产业学院),成都610059 [3]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [4]贵州省油气勘查开发工程研究院,贵阳550081

出　　处：《成都理工大学学报(自然科学版)》2025年第1期140-152,共13页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家自然科学基金面上项目(42202189);四川省科技计划项目(2024NSFSC0959)。

摘　　要：近10年来,页岩气的勘探开发已取得重要进展,但对于传统意义上作为“油气烃源岩或盖层”的富有机质泥(页)岩能否作为“储层”还需验证。利用薄片鉴定、扫描电镜观测、分子示踪剂扩散实验、孔隙度与脉冲渗透率测试等手段,系统分析了泥(页)岩的储集属性特征。结果表明:(1)富有机质泥(页)岩发育有机质孔隙(10~100 nm)和无机孔隙(10~500 nm),孔隙度在1%~10%之间,具备储集油气的有效空间;(2)富有机质泥(页)岩在高演化阶段(高成熟至过成熟阶段)发育与裂解气同期形成的大量微-纳米级有机质气孔,天然气能就近无阻力充注于有机质孔隙中,在克服运移阻力后经过短距离运移可以充注于与有机质孔连通的无机孔隙中;(3)泥(页)岩微-纳米孔隙系统呈网状连通,页岩渗透率小于0.01×10^(-3)μm^(2),天然气分子可以沿网状连通孔隙运移,但流动速度缓慢。综合分析认为富有机质泥(页)岩具备形成天然气储层的3个必要条件(储气空间、储集天然气和天然气流动),可作为“页岩气储层”,但能否作为油的储层,还需进一步验证,其他类型的泥(页)岩层只能被作为盖层及烃源岩层对待。In the last decade,shale gas exploration and development has made significant progress.However,whether organic-rich mud shale,traditionally considered as source rock or cap rock,can be defined as a reservoir still needs to be verified.In this paper,thin section identification,scanning electron microscope observations and measurements,molecular tracer diffusion experiment,and porosity and permeability tests are employed to analyze the reservoir properties and characteristics of shale systematically.The results show that(1)organic matter pores(10~100 nm)and inorganic matter pores(10~500 nm)have developed in the organic-rich matter shale,and their porosity is between 1%and 10%,indicating an effective space for oil and gas storage.(2)In the high-evolution stage(high maturity to over-maturity stage),abundant macro-nano organic matter pores have developed in the organic-rich shale,which formed simultaneously with injected cracked gas.Such gas can be injected into organic matter pores without migration resistance(at short distances);however,migration resistance is encountered when gas is injected into inorganic matter pores connected with organic matter pores.(3)The micro-nano pore system of the shale is network-like connections,and the permeability of the shale is less than 0.01×10^(-3)μm^(2).Gas molecules can migrate along the network-connected pores,but the flow rate is slow.In summary,organic-rich matter shale can be defined as a shale gas reservoir if it meets three necessary conditions:suitable reservoir space,stored gas,and suitable gas flow.But further verification of these conditions is required for shale oil reservoir.Other types of shale that do not satisfy these conditions can only be defined as cap rock and source rock.

关 键 词：页岩气储层 有机质气孔 微孔隙类型 连通网络 气体分子流动 

分 类 号：TE122[石油与天然气工程—油气勘探]