渤海湾盆地沧东凹陷孔二段湖相页岩油甜点评价与勘探实践  

Sweet spots evaluation and exploration of lacustrine shale oil of the second member of Paleogene Kongdian Formation in Cangdong Sag,Bohai Bay Basin

作　　者：韩文中[1,3] 赵贤正[2] 金凤鸣[2] 蒲秀刚[2] 陈世悦[3] 牟连刚[2] 张伟[2] 时战楠 汪虎 HAN Wenzhong;ZHAO Xianzheng;JIN Fengming;PU Xiugang;CHEN Shiyue;MU Liangang;ZHANG Wei;SHI Zhannan;WANG Hu(PetroChina Dagang Oilfield Company,Tianjin 300280,China;China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油大港油田公司勘探开发研究院,天津300280 [2]中国石油大港油田公司,天津300280 [3]中国石油大学(华东),山东青岛266580

出　　处：《石油勘探与开发》2021年第4期777-786,共10页Petroleum Exploration and Development

基　　金：中国石油科技重大专项“大港油区效益增储稳产关键技术研究与应用”(2018E-11);“陆相中高成熟度页岩油勘探开发关键技术研究与应用”(2019E-2601)。

摘　　要：基于岩心、薄片、X射线衍射、岩石热解、CT扫描、核磁共振及试油资料,研究黄骅坳陷沧东凹陷古近系孔二段陆相页岩层系宏观及微观的组分、沉积结构特征及页岩油甜点评价标准和方法,确定页岩油水平井最佳甜点箱体。根据优势岩石类型、韵律结构及测井曲线特征,建立了薄层状灰云质页岩、纹层状混合质页岩、纹层状长英质页岩和层状灰云质页岩4类页岩岩相,将孔二段一亚段划分为(PS1—PS4)4个准层序。PS1页岩孔隙度大于6%,黏土含量小于20%,S1值小于4 mg/g;PS2页岩纹层结构发育,大孔径孔喉、连通性较好、有机碳及可动烃含量高,S1值大于4 mg/g、TOC值为2%~6%、黏土含量小于20%、孔隙度大于4%;PS3页岩S1值大于6 mg/g,黏土含量为20%~30%,孔隙度小于4%;PS4页岩TOC值偏低、含油性相对较差。建立了游离烃含量(S1)、页岩韵律结构、黏土含量、TOC及孔隙度等5参数的页岩油评价分类标准,以及5参数赋权重甜点层定量评价方法和评价指数EI。综合分析分析认为PS2最优,是页岩油地质-工程双甜点,其次是PS3和PS1,前者侧重于页岩油地质甜点而后者则偏于工程甜点,最后为PS4。优选PS2和PS3两套页岩油甜点钻探,多口直井和水平井获得高产,其中1701H井稳产623 d、累产超万吨,展示孔二段页岩油良好的勘探前景。图9表5参33。Based on the systematic data of cores,thin section,X-ray diffraction,rock pyrolysis,CT scanning,nuclear magnetic resonance and oil testing of Paleogene Kong 2 Member in Cangdong sag,Huanghua depression,the macro and micro components,sedimentary structure characteristics of the Kong 2 Member shales,and evaluation standard and method of shale oil sweet spot are studied,and the best shale sections for horizontal wells are determined.According to the dominant rock type,rhythmic structure and logging curve characteristics,four types of shale lithofacies are established,namely,thin-layered dolomitic shale,lamellar mixed shale,lamellar felsic shale,and bedded dolomitic shale,and the Kong 21 sub-member is divided into four parasequences PS1 to PS4.The study shows that PS1 shale has a porosity higher than 6% and clay content of less than 20%,but S1 of less than 4 mg/g;PS2 shale has laminar structure,large size and good connectivity of pores and throats,high TOC(2%-6%)and high content of movable hydrocarbon,S1 of over 4 mg/g,clay content of less than 20%,and porosity of more than 4%;PS3 shale has a S1 value higher than 6 mg/g and a clay content of 20%-30%,but porosity of less than 4%;PS4 shale has low TOC and poor oil-bearing property.The shale oil classification and evaluation criteria based on five parameters,free hydrocarbon content S1,shale rhythmic structure,clay content,TOC and porosity,and the evaluation method of the weighted five parameters and the evaluation index EI are established.Comprehensive analysis shows that PS2 is the best,which is the geological engineering double sweet spot of shale oil,followed by PS3 and PS1,the former focuses on the geological sweet spot of shale oil,the latter on the engineering sweet spot,and the last is PS4.Two sets of shale oil sweet spots,PS2 and PS3,are selected and several vertical and horizontal wells drilled in these sweet spots have achieved high oil production.Among them,Well 1701H has produced stably for 623 days,with cumulative production of over 10000 tons,showing a go

关 键 词：页岩岩相 韵律结构 赋权重定量评价 页岩油甜点 页岩油评价标准 沧东凹陷 渤海湾盆地 古近系 孔二段 

分 类 号：TE122[石油与天然气工程—油气勘探]