鄂尔多斯盆地华池地区长7_(3)亚段深水重力流砂体发育规模定量表征——以Y1-1、Y2-1水平井钻遇砂体为例  

Quantitative characterization of deep-water gravity flow sand body in the Chang 7_(3) submember in Huachi area,Ordos Basin:A case study of sandbodies encountered drilling of Y1-1 and Y2-1 horizontal wells

作　　者：王秀娟 辛红刚[2,3] 程党性[2,3] 陈冬霞[1,4] 李树同[5,6] WANG Xiujuan;XIN Honggang;CHENG Dangxing;CHEN Dongxia;LI Shutong(College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an 710018,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,China;National Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Beijing 102249,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Science,Lanzhou 730000,China;Key Laboratory of Oil and Gas Resources Exploration and Evaluation in Gansu Province,Lanzhou 730000,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [3]低渗透油气田勘探开发国家工程实验室,陕西西安710018 [4]油气资源与工程全国重点实验室,中国石油大学(北京),北京102249 [5]中国科学院西北生态环境资源研究院,甘肃兰州730000 [6]甘肃省油气资源勘探与评价重点实验室,甘肃兰州730000

出　　处：《天然气地球科学》2024年第12期2142-2154,共13页Natural Gas Geoscience

基　　金：国家自然科学基金面上项目(编号:41772142);甘肃省重点研发计划-工业类(编号:23YFGM0002);中国石油天然气股份公司科技重大专项“陆相页岩油规模增储上产与勘探开发技术研究”(编号:2023ZZ15);甘肃省科技计划项目(编号:22JRSRA045)联合资助。

摘　　要：深水重力流沉积的块状粉—细砂体是鄂尔多斯盆地长7段内页岩油勘探开发的主要“甜点”,定量、准确地刻画出粉—细砂体规模与空间分布,提高水平井砂体钻遇率,对该层系页岩油的成功开发至关重要。利用华池地区Y1-1、Y2-1水平井的岩心、录井及成像测井等资料,结合二维地震数据,对区内长7_(3)亚段重力流沉积砂体的岩性、组合结构、厚度、宽度及延伸方向进行了精细刻画,定量表征了不同类型砂体组的宽厚比及规模。研究表明,研究区长7_(3)亚段砂体的岩性主要为细砂岩和粉砂岩,矿物组成以石英(36.6%~42.3%)和长石(32.6%~45.6%)为主,黏土矿物含量为12.2%~18.6%。单期(个)砂体厚度一般为0.6~5.0 m,宽度多小于150 m,主要延SW→NE向展布;砂体组的结构可分为孤立型、间隔叠加型及连续叠加型3种,它们的宽厚比分别为95∶1(孤立型)、344∶1(间隔叠加型)及144∶1(连续叠加型),在NE方向上的长度为3 000~4 000 m。长7_(3)亚段下部砂体沉积连续性较好、厚砂体组(>5 m)分布范围广,而长7_(3)亚段中、上部砂体沉积连续性差、厚砂体组分布范围小。The blocky powdery fine sand bodies deposited by deep-water gravity flow are the main“sweet spot”for shale oil exploration and development in the seventh member of Yanchang Formation(Chang 7 Member)in Ordos Basin.Quantitatively and accurately characterizing the scale and spatial distribution of powdery fine sand bodies,improving the drilling rate of horizontal well sandbodies,is crucial for the successful development of shale oil in this layer.Using core,logging,and imaging logging data from the Y1-1 and Y2-1 horizontal wells in the Huachi area,combined with 2D seismic data,the lithology,combination structure,thickness,width,and extension direction of the gravity flow sedimentary sandbody in the Chang 7_(3) submember of the area were finely characterized,quantitatively characterizing the width to thickness ratio and scale of different types of sandbody groups.Research has shown that the lithology of the sandbody in the study area's Chang 7_(3) submember is mainly composed of fine sandstone and siltstone,with quartz(36.6%-42.3%)and feldspar(32.6%-45.6%)as the main mineral components,and clay mineral content ranging from 12.2%to 18.6%.The thickness of a single stage(individual)sandbody is generally 0.6-5.0 m,with a width mostly less than 150 m,mainly distributed in the SW→NE direction;the structure of the sandbody group can be divided into three types:isolated type,in⁃terval stacking type,and continuous stacking type.Their width to thickness ratio is 95∶1(isolated type),344∶1(interval stacking type),and 144∶1(continuous stacking type),respectively.The length in the NE direction is 3000-4000 m.The lower part of the Chang 73 submember has good sedimentary continuity and a wide distribu⁃tion range of thick sandbody groups(>5 m),while the middle and upper parts of the Chang 73 submember have poor sedimentary continuity and a small distribution range of thick sand body groups.

关 键 词：重力流 砂体组合类型 定量表征 水平井 长7段 

分 类 号：TE122.1[石油与天然气工程—油气勘探]