摘要
在渤海湾盆地保定凹陷清苑地区古近系东三段岩石学特征研究的基础上,从岩相描述、沉积微相识别以及地球物理响应特征分析3个方面入手,明确了其沉积相展布特征、沉积模式及控储机理,并预测了有利区。研究结果表明:①保定凹陷清苑地区东三段泥岩以氧化色为主,砂岩主要为岩屑质长石砂岩和长石质岩屑砂岩,岩石成分成熟度、结构成熟度低—中等,具明显的河流牵引流特征,沉积时气候干旱—半干旱,属于陆相淡水、氧化环境。②研究区可识别出9种岩相类型,包括4种细砂岩相、3种粉砂岩相和2种泥岩相;曲流河沉积可划分为河床滞留沉积、边滩、天然堤、牛轭湖、决口扇、泛滥平原等6种微相;具有中—高幅箱形、中—高幅钟形、中幅指形、中—低幅漏斗形、低幅线形等5种测井响应特征,地震上具有振幅中等—偏强、频率较高、连续性中等—较差的特征。③研究区平面上砂体呈南西—北东向展布,自下而上曲流河砂体厚度、分布范围逐渐减小,发育单一条带型和网状连片型两种曲流河沉积模式。④研究区沉积控储特征明显,边滩和河床滞留沉积微相储层物性最好,强而稳定的水动力条件、低黏土矿物含量和厚层砂体是优质储层形成的基础;Ⅰ类储层物性条件最好,垂向上主要分布在Ⅱ和Ⅲ油组,G77-70X,G77-30X等井区是下一步有利勘探目标。
Based on the study of petrological characteristics of Paleogene Dong 3 Member in Qingyuan area,Baoding Sag,Bohai Bay Basin,three aspects such as lithofacies description,sedimentary facies identification and analysis of geophysical response characteristics were analyzed,in order to clarify the sedimentary distribution characteristics,sedimentary model and the control mechanisms of sedimentation on reservoir.Meanwhile,the favorable zones were predicted in this area.The results show that:(1)The mudstone color of Dong 3 Member in Qingyuan area were mainly oxidation color,the sandstones were dominated by lithic feldspathic sandstone and feldspathic lithic sandstone,the rock of Dong 3 Member have low-middle compositional maturity and textural maturity,and have obvious river traction flow characteristics.During the deposition of the Dong 3 Member,the climate was arid and semi-arid,which indicated a terrestrial freshwater and oxidizing environment.(2)Nine lithofacies types can be identified in the study area,including four kinds of sandstone lithofacies,three kinds of siltstone lithofacies,two kinds of mud stone lithofacies.The study area developed meandering river facies,which can be divided into six microfacies:river bed retention sediment,point bar,natural levees,oxbow lake,crevasse splay,flood plain,five well logging response characteristics can be identified,including middle-high amplitude box-shaped,middle-high amplitude bell-shaped,middle amplitude finger-shaped,middle-low amplitude funnel-shaped,low amplitude linear,and the reservoir have moderate-strong ampitude,high frequency,middle and bad continuity on seismic section.The sand bodies were deposited in southwest-northeast trending in the plane,the thickness and distribution of the sand body of meandering river decreases from lower to upper,single belt type and network continuous sedimentary model of meandering river were established.(3)The sedimentation determined the reservoir characteristics in study area,the reservoirs physical properties of river bed retention sediment and point bar were the best microfacies,strong and stable hydrodynamic conditions,low content of clay mineral and thick sandbody were the basis of the formation of high-quality hydrocarbon reservoirs,the Ⅰ reservoir have the best physical properties,which were mainly distributed in the Ⅱ and Ⅲ oil-bearing formations in the vertical direction,well area G77-70X and G77-30X were the favorable target areas.
作者
薛辉
叶大帅
郭悦苗
陈柯童
吴健平
许梦婷
李雅雯
XUE Hui;YE Dashuai;GUO Yuemiao;CHEN Ketong;WU Jianping;XU Mengting;LI Yawen(Research Institute of Petroleum Exploration and Development of Huabei Oilfield Company,Renqiu 062550,Hebei,China)
出处
《岩性油气藏》
北大核心
2025年第2期139-152,共14页
Lithologic Reservoirs
基金
中国石油天然气股份有限公司华北油田公司项目“保定-饶阳凹陷重点层系沉积微相研究及有利区带优选”(编号:2023-HB-A06-02)资助。
关键词
曲流河
干旱气候
氧化环境
沉积控储作用
边滩
河床滞留
东三段
古近系
清苑地区
保定凹陷
渤海湾盆地
meandering river
arid climate
oxidation environment
controls of sedimentation on reservoir
point bar
river bed retention
Dong 3 Member
Paleogene
Qingyuan area
Baoding Sag
Bohai Bay Basin
