鄂尔多斯盆地横山—吴堡地区本溪组招贤页岩储层特征及勘探潜力  

Reservoir characteristics and exploration potential evaluation of Zhaoxian shale in Benxi Formation,Hengshan⁃Wupu area,Ordos Basin

作　　者：王康乐[1,2] 殷亮亮[1,2] 宋佳瑶 张琴 裴文超[1,2] 孟艳军 高万里 张欣宇[5] 邱振 WANG Kangle;YIN Liangliang;SONG Jiayao;ZHANG Qin;PEI Wenchao;MENG Yanjun;GAO Wanli;ZHANG Xinyu;QIU Zhen(National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields,Xi'an 710018,China;Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi'an 710018,China;PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;National Energy Shale Gas R&D(Experiment)Centre,Langfang 065007,China;College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]低渗透油气田勘探开发国家工程实验室,陕西西安710018 [2]中国石油长庆油田公司勘探开发研究院,陕西西安710018 [3]中国石油勘探开发研究院,北京100083 [4]国家能源页岩气研发(实验)中心,河北廊坊065007 [5]太原理工大学矿业工程学院,山西太原030024

出　　处：《天然气地球科学》2024年第12期2196-2214,共19页Natural Gas Geoscience

基　　金：中国石油长庆油田公司科技项目“油气勘探重点领域综合技术研究(编号:2023DJ0107)”;国家科技重大专项“鄂尔多斯盆地东缘深层煤层气、煤系地层天然气开发示范工程”(编号:2016ZX05065)联合资助。

摘　　要：鄂尔多斯盆地东部海陆过渡相页岩气勘探已取得重大突破,但相关研究明显滞后于海相页岩气领域。以鄂尔多斯盆地东部横山—吴堡地区本溪组晋祠段招贤页岩样品为研究对象,综合镜质体反射率(RO)、总有机碳(TOC)测试、薄片鉴定、扫描电镜、X射线全岩衍射、孔渗测试、低温液氮吸附、甲烷等温吸附、含气量及力学性质等实验,综合表征招贤页岩储层特征,探讨孔隙结构参数及TOC含量对页岩吸附能力的影响,最终对招贤页岩的勘探潜力开展了综合分析。结果表明:(1)研究区招贤页岩为典型海陆过渡相页岩,岩矿组成复杂,黏土矿物及长英质矿物含量较高,平均占比分别为47.4%和36.4%。(2)招贤页岩有机质类型以Ⅱ2型和Ⅲ型干酪根为主,成熟度较高,有机质含量平均为5.30%,富有机质页岩占比较高,生气能力强。(3)招贤页岩微纳米级裂缝和孔隙发育,微裂隙在有机质和无机矿物中均有发育,缝宽介于0.01~1μm之间;液氮吸附孔隙类型以狭缝型孔隙为主,平均孔径均值为13.67 nm,比表面积均值为6.56 m^(2)/g,总孔隙体积均值为0.017 6 cm^(3)/g;BET比表面积与孔隙结构分形维数呈正相关关系,与平均孔径呈负相关关系。(4)招贤页岩孔渗偏低,兰氏体积平均为3.14 cm^(3)/g,含气量平均为1.52 cm^(3)/g,脆性指数平均为0.526,杨氏模量平均为40.88 GPa,泊松比平均为0.22。(5)研究区招贤页岩储层条件总体上与大宁—吉县地区山2段相当,资源条件优越,可改造性良好,具有较大的页岩气勘探潜力。Significant breakthroughs have been made in the exploration of marine-continental transitional shale gas in the eastern Ordos Basin,but the related research obviously lags behind that of marine shale gas.Taking the Zhaoxian shale samples from Benxi Formation in Hengshan-Wupu area in the eastern Ordos Basin as the re⁃search object,the characteristics of the Zhaoxian shale reservoir in the area were comprehensively characterized by comprehensive experiments such as vitrinite reflectance,total organic carbon(TOC),thin section,scanning electron microscopy(SEM),X-ray whole rock diffraction(XRD),pore permeability,low-temperature liquid nitrogen adsorption,methane isothermal adsorption,gas content and mechanical properties tests in this paper.The effects of pore structure parameters and TOC content on the adsorption capacity of shale were discussed,and the exploration potential of the Zhaoxian shale in the study area was finally comprehensively analyzed.The results show that:(1)Zhaoxian shale in the study area is a typical marine-continental transitional shale,with complex rock and mineral composition,high clay minerals and felsic minerals,with an average proportion of 47.4%and 36.4%,respectively;(2)The organic matter types of Zhaoxian shale are mainly Types I2 and III kerogen,with high maturity and an average organic matter content of 5.30%.The organic-rich shale accounts for a relatively high proportion and has strong gas generation capacity.(3)Micro-nano scale fractures and pores are developed in Zhaoxian shale,and micro-fractures are developed in both organic matter and inorganic miner⁃als,with fracture widths ranging from 0.01 to 1μm.The pore types of liquid nitrogen adsorption were mainly narrow pores,with an average pore size of 13.67 nm,an average specific surface area of 6.56 m^(2)/g,and an aver⁃age total pore volume of 0.0176 cm^(3)/g.BET specific surface area is positively correlated with the fractal dimen⁃sion of pore structure,and negatively correlated with the average pore size.(4)The pore permeab

关 键 词：储层特征 孔隙结构 本溪组 招贤页岩 勘探潜力 横山—吴堡地区 

分 类 号：TE121.1[石油与天然气工程—油气勘探]