沾化凹陷沙河街组湖相泥页岩夹层特征及测井识别方法  

Logging identification method of lacustrine shale interlayers of Shahejie Formation in Zhanhua Sag

作　　者：赵笑笑 闫建平[1,2,3] 王敏 何贤[2] 钟光海 王军[4] 耿斌[4] 胡钦红[6] 李志鹏 ZHAO Xiaoxiao;YAN Jianping;WANG Min;HE Xian;ZHONG Guanghai;WANG Jun;GENG Bin;HU Qinhong;LI Zhipeng(State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Key Laboratory of Tectonics and Petroleum Resources,China University of Geosciences,Ministry of Education,Wuhan 430074,China;Research Institute of Exploration and Development,Sinopec Shengli Oilfield Company,Dongying 257015,Shandong,China;Research Institute of Shale Gas,PetroChina Southwest Oil&Gas Field Company,Chengdu 610500,China;Department of Earth and Environmental Sciences,University of Texas at Arlington,Arlington 76019,TX,USA)

机构地区：[1]油气藏地质及开发工程国家重点实验室(西南石油大学),成都610500 [2]西南石油大学地球科学与技术学院,成都610500 [3]中国地质大学构造与油气资源教育部重点实验室,武汉430074 [4]中国石化胜利油田分公司勘探开发研究院,山东东营257015 [5]中国石油西南油气田分公司页岩气研究院,成都610500 [6]美国德克萨斯大学阿灵顿分校地球与环境科学系,德克萨斯州阿灵顿76019

出　　处：《岩性油气藏》2022年第1期118-129,共12页Lithologic Reservoirs

基　　金：中国石油-西南石油大学创新联合体科技合作项目“川南深层与昭通中浅层海相页岩气规模效益开发关键技术研究”(编号:2020-CX020000);胜利油田科技攻关项目“页岩油地质储量计算关键参数研究”(YKK2013)。

摘　　要：为了研究沾化凹陷沙三段湖相页岩夹层与页岩油产能之间的关系,在分析岩心描述、薄片鉴定、X射线衍射、扫描电镜、压汞等资料的基础上,利用反褶积方法处理测井资料识别夹层类型。结果表明:(1)砂质夹层和灰质夹层的脆性矿物含量高,易形成裂缝。其中砂质夹层长英矿物和灰质夹层碳酸盐岩矿物的质量分数高达46.7%,57.95%;(2)夹层中发育异常压力缝、矿物收缩缝、层间缝,在砂质夹层中还发育构造缝。出现裂缝的夹层平均渗透率高达7.59 mD;(3)夹层主要发育微—纳米级孔隙,有粒间孔、溶蚀孔和晶间孔,孔隙连通性较好。粒间孔常见于砂质夹层。溶蚀孔常见于灰质夹层,大孔隙较多;(4)夹层测井曲线响应特征:砂质夹层和灰质夹层都表现为低自然伽马和高电阻率特征,砂质夹层具有自然伽马在高背景下低回返、三孔隙度曲线和深侧向电阻率向右偏移,灰质夹层的三孔隙度曲线呈明显向右"靠拢"。利用反褶积方法处理后的自然伽马、深侧向电阻率曲线进行重叠可快速识别夹层且分辨率更高、更直观,能够有效地识别湖相泥页岩夹层,为页岩油评价提供依据。To study the relationship between lacustrine shale interlayer and shale oil productivity of the third member of Shahejie Formation in Zhanhua Sag,based on the analysis of core description,thin section identification,X-ray diffraction,scanning electron microscope and mercury injection,deconvolution method was used to process logging data to identify interlayer types.The results show that:(1)The content of brittle minerals in sandy interlayers and calcareous interlayers is high,which is easy to form fractures.The mass fraction of quartz-feldspar and calcite-dolomite is as high as 46.7% and 57.95% respectively.(2)Abnormal pressure fractures,mineral contraction fractures and interlayer fractures are developed in the interlayer,and structural fractures are also developed in the sandy interlayer.The average permeability of fractured interlayer is 7.59 m D.(3)The interlayers mainly develop micro and nano pores with good pore connectivity,including intergranular pores,dissolved pores and intergranular pores.Intergranular pores are shown in sandy interlayer.Dissolved pores are shown in calcareous interlayer,with more macropores.(4)The logging curve response characteristics of the interlayers are as following:both sandy interlayers and limestone interlayers are characterized by low natural gamma and high resistivity,sandy interlayer has low return under high natural gamma background,three-porosity curve and deep lateral resistivity shift to the right and three-porosity curve of limestone interlayer is obviously closed to the right.Overlapping the natural gamma and deep lateral resistivity curves processed by deconvolution method,it is quick to identify the interlayer with higher resolution and more intuitive,and effective to identify the lacustrine shale interlayer,which provides a basis for shale oil evaluation.

关 键 词：页岩油 砂质夹层 灰质夹层 测井识别 反褶积 曲线重叠法 沙河街组 沾化凹陷 

分 类 号：P631[天文地球—地质矿产勘探]