摘要
四川盆地及周缘下寒武统富有机质页岩分布范围广、厚度大,是页岩气勘探的重要接替层位。以多口重点钻井岩心资料为基础,利用扫描电镜、氮气吸附等实验分析方法,对下寒武统富有机质页岩的孔隙类型、孔隙结构等进行系统研究,并探讨了下寒武统富有机质页岩孔隙发育的主要控制因素。结果表明:不同地区的下寒武统富有机质页岩孔隙发育存在显著的差异,孔隙度与TOC含量之间关系复杂,受到有机质组成和热成熟度的影响,主要表现为有机质组成和热成熟度控制了有机孔的发育。下寒武统富有机质页岩孔隙结构多样,且不同成熟度的页岩具有不同的孔隙结构,随着热成熟度的增加,页岩微孔消失、孔容和比表面积均减小。热成熟度是四川盆地及周缘下寒武统页岩气勘探与评价的最重要参数之一。
Lower Cambrian organic-rich shale is widely distributed with great thickness in Sichuan Basin and its periphery,which is the significant replacing layer of shale gas exploration.Based on the shale cores from several key wells,this paper systematically investigated the pore types and structures of Lower Cambrian organic-rich shale using SEM and low pressure nitrogen adsorption,and discussed the main controlling factors of pore development of Lower Cambrian organic-rich shale.The results indicate that there are significant differences between Lower Cambrian organic-rich shale from different regions.The relationship between total organic carbon content(TOC)and porosity is complex due to the influences from thermal maturation and organic matter composition which controls the development of organic matter-hosted pores.The Lower Cambrian organic-rich shale has various pore structures.With increasing maturation,pore structure changes by micropore vanishing,and specific surface area and pore volume decrease.Therefore,thermal maturation is one of the most important parameters for shale gas exploration and assessment of the Lower Cambrian in Sichuan Basin and its periphery.
作者
熊亮
Xiong Liang(Exploration and Production Research Institute,SINOPEC Southwest Company,Chengdu 610041,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2019年第9期1319-1331,共13页
Natural Gas Geoscience
基金
中国石化科技部重点科技项目“深层页岩气综合评价及开发技术政策”(编号:P18058-1)资助
关键词
下寒武统
孔隙发育
热成熟度
有机质组成
主控因素
Lower Cambrian
Pore development
Thermal maturation
Organic matter composition
Controlling factor
