滇东曲靖地区下寒武统筇竹寺组泥页岩储层特征研究

THE CHARACTERISTICS OF SHALE RESERVOIR FROM QIONGZHUSI FORMATION IN LOWER CAMBRIAN IN QUJING AREA,EASTERN YUNNAN PROVINCE,CHINA:A CASE STUDY OF WELL QUYE NO.1

下寒武统筇竹寺组页岩是南方页岩气勘查开发重点关注的层位之一,但滇东地区下寒武统筇竹寺组黑色页岩储层研究程度较低。样品采自2014年新钻的曲页1井,对下寒武统筇竹寺组黑色泥页岩进行全岩和粘土矿物X衍射分析、TOC、岩石物性、比表面积等测试和扫描电镜实验,综合分析了滇东曲靖地区筇竹寺组泥页岩储层特征及孔隙类型。结果表明:滇东曲靖地区下寒武统筇竹寺组泥页岩矿物组成主要是石英(44.75%)、粘土矿物(25.47%)、长石(16.44%);发育粒间孔、粒内孔和有机孔3种类型孔隙;有机质孔隙发育,以中孔为主,具有一定的页岩气勘探开发潜力;页岩储层自上而下孔隙体积有逐渐变小的趋势,但在井深400 m^500 m发育高孔隙体积;泥页岩储集性能的重要指标——孔隙度主要受有机质含量及发育程度的制约。

Shale from Qiongzhusi formation in Lower Cambrian is one of the most important focuses in shale gas exploration and development in South China;however,the black shale reservoir from Qiongzhusi formation in Lower Cambrian in eastern Yunnan province stays in a low level of study.Take Well Quye No.1drilled in2014as an example,on the black shales from Qiongzhusi formation in Lower Cambrian,X-ray diffraction analysis of the whole rock and clay minerals are made;tests and SEM experiments like TOC,physical property and specific surface area are conducted;the characteristics and types of shale reservoir are analyzed comprehensively.The results show that shales are mainly composed of quartz(44.75%),clay minerals(25.47%)and feldspar(16.44%),consisting of three major pore types,which are intergranular pore,intragranular pore and organic-matter pore.It is worth mentioning that organic-matter pores are abundant and of great importance,in which mesopores are the main force with a certain potential of shale gas exploration and development.The volumes of pores decrease with the depth,and with increasing TOC,micropore volumes relatively increase.The porosity is mainly restricted by the organic-matter content and the development degree.