四川盆地西南部东瓜场地区侏罗系沙溪庙组沉积特征及有利储层预测  

The deposition characteristics and favorable reservoir prediction of Jurassic Shaximiao Formation in Dongguachang area,southwestern Sichuan Basin

作　　者：吴冠桦 刘宏[1] 宋林珂 曾琪 杨涛 WU Guanhua;LIU Hong;SONG Linke;ZENG Qi;YANG Tao(Sichuan Key Laboratory of Natural Gas Geology,Southwest Petroleum University,Chengdu 610500,China;Tight Oil and Gas Exploration and Development Project Department,Southwest Oil and Gas Field Branch,PetroChina,Chengdu 610500,China;Northwest Sichuan Gas Mine,Southwest Oil and Gas Field Branch,PetroChina,Jiangyou 621000,Sichuan,China)

机构地区：[1]西南石油大学天然气地质四川省重点实验室,成都610500 [2]中国石油西南油气田公司致密油气勘探开发项目部,成都610500 [3]中国石油西南油气田公司川西北气矿,四川江油621000

出　　处：《岩性油气藏》2025年第2期92-102,共11页Lithologic Reservoirs

基　　金：国家自然科学基金“成岩体系演化对致密砂岩储层流体-岩石相互作用的控制项目”(编号:41872154)资助。

摘　　要：针对四川盆地西南部东瓜场地区侏罗系沙溪庙组河道砂体分布规律不清的问题,基于地震沉积学理论,结合钻井岩心、测井、地震等资料,通过地震岩性分析、地层切片、RGB属性融合等技术,对四川盆地侏罗系沙溪庙组沉积体系展开了研究。研究结果表明:①东瓜场地区侏罗系沙溪庙组主要发育2个三级层序(SQ1,SQ2)、5个四级层序(ssq1—ssq5),其中SQ1属于湖退体系域,SQ2属于湖侵体系域。②研究区沙溪庙组沉积时期,主要发育浅水三角洲沉积,可进一步划分为三角洲平原和三角洲前缘2种亚相,三角洲平原发育于ssq2和ssq3,三角洲前缘发育于ssq1,ssq4和ssq5。③研究区沙溪庙组河道砂体受基准面旋回和物源供给影响,ssq1—ssq3可容纳空间较小,物源供给充足,河道规模较大,以叠置型河道和侧切型河道为主;ssq4—ssq5可容纳空间较大,物源供给较弱,河道相对独立发育,规模较小。③研究区大规模连通河道砂体主要发育于ssq1—ssq3的河道中,储层物性好,为勘探有利区。In response to the unclear distribution patterns of channel sand bodies of Jurassic Shaximiao Formation in Dongguajing area of Sichuan Basin,this study utilized seismic sedimentology theory and integrated data from drilling,core samples,well logging,and seismic data.Various techniques,including seismic lithology analysis,stratigraphic slicing,and RGB attribute fusion,were employed to study the sedimentary system of the Shaximiao Formation in the research area.The results show that:(1)In the Dongguajing area,the Shaximiao Formation mainly consists of two third-order sequences(SQ1-SQ2)and five fourth-order sequences(ssq1-ssq5).SQ1 belongs to the overall lake retreat system,while SQ2 belongs to the lake transgression system.(2)During the sedimentation period of the Shaximiao Formation,the dominant sedimentary facies in the study area were shallow-water delta deposits,which can be divided into two types:delta plain and delta front subfacies.Delta plain subfacies developed during ssq2 and ssq3,while delta front subfacies developed during ssq1,ssq4,and ssq5.(3)The development of channel sand bodies in the Shaximiao Formation is influenced by base-level cycles and sediment supply.The ssq1-ssq3 can accommodate lower space and have stronger sediment supply,resulting in larger channel sizes with overlapping and incised channel configurations.The ssq4-ssq5,on the other hand,have higher accommodation space and weaker sediment supply,leading to relatively independent and smaller channel development.(4)Large-scale connected channel sand bodies are mainly found in the channels of ssq1-ssq3,with the characteristics of good reservoir,and shoes are the favorable reservoir.

关 键 词：地震沉积学 浅水三角洲 叠置型河道 侧切型河道 基准面旋回 物源供给 沙溪庙组 侏罗系 东瓜场地区 四川盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]