基于核磁共振表征渝西地区五峰组-龙一_(1)亚段页岩储层孔隙结构及非均质性  

Characterization of Pore Structure and Heterogeneity of Shale Reservoir from Wufeng Formation-Sublayers Long-1_(1) in Western Chongqing Based on Nuclear Magnetic Resonance

作　　者：王子萌 蒋裕强[1,2] 付永红 雷治安[3] 徐昌海 袁竟舟 文冉 王占磊 谷一凡 尹兴平[1,2] Wang Zimeng;Jiang Yuqiang;Fu Yonghong;Lei Zhian;Xu Changhai;Yuan Jingzhou;Wen Ran;Wang Zhanlei;Gu Yifan;Yin Xingping(School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Unconventional Reservoir Evaluation Laboratory,UOGKL,CNPC,Chengdu 610500,China;Chongqing Shale Gas Exploration and Development Company Limited,Chongqing 400025,China;Research Institute of Exploration and Development PetroChina Southwest Oil and Gas Field.Company,Chengdu 610041,China;PetroChina Southwest Oil&Gas Field Company,Chengdu 610051,China;Sichuan Changning Natural Gas Development Company Limited,Chengdu 610056,China)

机构地区：[1]西南石油大学地球科学与技术学院,四川成都610500 [2]中国石油非常规重点实验室储层评价实验室,四川成都610500 [3]重庆页岩气勘探开发有限责任公司,重庆400025 [4]西南油气田公司公司勘探开发研究院,四川成都610041 [5]西南油气田分公司开发事业部,四川成都610051 [6]四川长宁天然气开发有限责任公司,四川成都610056

出　　处：《地球科学》2022年第2期490-504,共15页Earth Science

基　　金：中石油-西南石油大学创新联合体项目二课题一专题四“复杂地质条件下川南深层/昭通中浅层海相页岩气赋存机制及控制因素研究”(No.2020CX020104);四川省应用基础研究项目“海相页岩气建产核心区智能评价系统研究(省重)”(No.2019YJ0346);四川省苗子工程重点项目“基于压裂液返排规律评价页岩气储层压裂效果的方法研究”(No.2019JDRC0095);高等学校学科创新引智计划(111计划)“深层海相页岩气高效开发学科创新引智基地”(No.D18016)。

摘　　要：选取渝西地区五峰组-龙一_(1)亚段富有机质页岩开展场发射扫描电镜、核磁共振和X射线衍射等实验,在图像处理和多重分形理论的基础上,分析了页岩储层孔隙结构特征及非均质性.结果表明:(1)扫描电镜分析认为,研究区有机孔平均孔径偏小,<50 nm的有机孔数量占比82%,>100 nm的有机孔面孔率占比52%;(2)依据核磁T_(2)谱峰形态划分为Ⅰ~Ⅲ类,分别为单峰、双峰和三峰3种类型,Ⅲ类页岩储层孔径、孔隙度较大,具备更优越的储集条件和渗流能力;(3)基于多重分形理论表征储层非均质性,石英含量越高,黏土含量越低非均质性越弱,进而控制着孔隙度和渗透率的大小.多重分形参数与矿物组分、物性参数的联系有效表征了储层孔隙结构,并为其非均质性的评估提供了新的视角.Select the organic-rich shale of the Wufeng Formation-sublayers Long-1_(1) in western Chongqing to carry out field emission scanning electron microscopy,nuclear magnetic resonance and X-ray diffraction experiments.Based on image processing and multifractal theory,the pore structure of the shale reservoir was analyzed.Characteristics and heterogeneity.The results show that:(1)Scanning electron microscopy analysis shows that the average pore size of organic pores in the study area is too small.The number of organic pores<50 nm accounted for 82%,and the number of organic pores>100 nm accounted for 52%;(2)According to the NMR T_(2) spectrum peak shape,it is divided into categoriesⅠ~Ⅲ,which are single-peak,double-peak and three-peak respectively.The shale reservoir of typeⅢhas larger pore size and porosity,and has better storage conditions and seepage capacity;(3)Based on the multifractal theory to characterize the heterogeneity of the reservoir,the higher the quartz content,the lower the clay content,the weaker the heterogeneity,which in turn controls the porosity and permeability.The relationship between multifractal parameters and mineral components and physical property parameters effectively characterizes the pore structure of the reservoir and provides a new perspective for the evaluation of its heterogeneity.

关 键 词：页岩储层 孔隙结构 核磁共振 多重分形 非均质性 油气地质 

分 类 号：P618[天文地球—矿床学]