潜江凹陷潜江组页岩中可溶有机质赋存空间表征及影响因素分析  

Spatial Characterization and Influencing Factors of Soluble Organic Matter in Shale of Qianjiang Formation in Qianjiang Depression

作　　者：孙中良 王芙蓉[1] 侯宇光[1] 何生[1] 韩元佳[1] 罗京 郑有恒[2] 吴世强[2] Sun Zhongliang;Wang Furong;Hou Yuguang;He Sheng;Han Yuanjia;Luo Jing;Zheng Youheng;Wu Shiqiang(Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education,China University of Geosciences(Wuhan),Wuhan 430074,China;Research Institute of Exploration and Development,Jianghan Oilfield Branch Company,SINOPEC,Wuhan 430223,China)

机构地区：[1]中国地质大学(武汉)构造与油气资源教育部重点实验室,武汉430074 [2]中国石化江汉油田分公司勘探开发研究院,武汉430223

出　　处：《地质科技情报》2019年第6期81-90,共10页Geological Science and Technology Information

基　　金：国家科技重大专项(2017ZX05049-005);国家自然科学基金项目(41772143)

摘　　要：为揭示潜江凹陷潜江组34段第10韵律(E q 3104)页岩中可溶有机质的赋存空间及其影响因素,采用XRD、索氏抽提、低温氮气吸附、高压压汞、扫描电镜、TOC测试、热解等手段,以抽提前后页岩样品的孔隙结构变化特征为基础,揭示页岩中可溶有机质的赋存空间、孔隙类型和孔隙结构,进而探讨影响页岩孔隙结构变化的主要因素。研究表明,研究区页岩孔隙类型主要为粒间孔、黏土矿物层间孔。扫描电镜和能谱分析表明,页岩中可溶有机质主要赋存在粒间孔和黏土矿物层间孔中。低温氮气吸附实验结果显示页岩孔隙结构分为2种类型,一种以四周开放的平板状孔隙为主,孔隙多为宏孔(孔径>50 nm),抽提后孔隙结构未发生改变,仅增加了部分介孔-宏孔;另一种孔隙类型较为复杂,多为开放型圆柱状及平板状孔隙,存在较多的宏孔(孔径>50 nm),抽提后小孔径(孔径2~10 nm)孔隙增加较多,孔隙结构更为复杂。石英及黏土矿物的存在促进了微孔及介孔的发育,有利于可溶有机质在微孔以及介孔中的赋存,白云石促进了宏孔的发育,有机质主要赋存于生物成因的白云石粒间孔内。In order to reveal the storage space and influencing factors of soluble organic matter in the 10th rhythm shale of the 34th member(E q 3 10 4) of Qianjiang Formation in Qianjiang Sag.In this study, XRD, Soxhlet extraction, low temperature nitrogen adsorption, high pressure mercury intrusion, scanning electron microscopy, TOC test, pyrolysis and other means were used to reveal the pore structure changes of shale samples after extraction, to reveal the existence space, pore type and pore structure of soluble organic matter in shale, and then explore the main factors affecting the change of pore structure in shale. This study shows that the shale pore types in the study area are mainly intergranular pores and interbedded pores of clay minerals. Scanning electron microscopy and energy spectrum analysis shows that the soluble organic matter in the shale is mainly composed of intergranular pores and interbedded pores of clay minerals.The results of low temperature nitrogen adsorption experiments indicates that the shale pore structure is divided into two types, one, mainly open flat plate-shaped pores, and the other, mostly macropores (>50 nm). The pore structure has not changed after extraction, only some mesopores and macropores have been added. Another type of pore is more complex, mostly open cylindrical and flat pores, with more macropores (>50 nm). After extraction, the pore size(2-10 nm) increases, and the pore structure becomes more complicated. The presence of quartz and clay minerals promotes the development of micropores and mesopores, which is beneficial to the existence of soluble organic matter in micropores and mesopores. Dolomite promotes the development of macropores, and organic matter is mainly stored in biogenic intergranular dolomite pores.

关 键 词：氮气吸附 高压压汞 抽提 可溶有机质 孔隙结构 

分 类 号：P618.12[天文地球—矿床学]