重力流沉积特征及其对油气开发的影响——以华庆地区B井区长6_(3)储层为例  

Gravity flow sedimentary characteristics and their impacts on oil and gas development:A case study of Chang 6_(3)reservoir in wellblock B of Huaqing area

作　　者：骆浩楠 赵永刚 苏珍 刘冰雷 丁留洋 LUO Haonan;ZHAO Yonggang;SU Zhen;LIU Binglei;DING Liuyang(School of Earth Sciences and Engineering of Xi'an Shiyou University,Xi'an,Shaanxi 710065,China;Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi'an,Shaanxi 710065,China)

机构地区：[1]西安石油大学地球科学与工程学院,陕西省西安市710065 [2]陕西省油气成藏地质学重点实验室

出　　处：《录井工程》2024年第4期99-107,共9页Mud Logging Engineering

基　　金：国家自然科学基金青年项目“不同应力系统作用下陆相页岩油储层纳米孔缝变形及扩展微观机理研究”(编号:42302167);中国石油天然气股份有限公司长庆油田分公司项目“华庆油田长6油藏大斜度井合理注采技术政策研究”(编号:CYSC2022-483)。

摘　　要：华庆地区B井区位于鄂尔多斯盆地西南部,长6_(3)储层是该井区的主力层位,其沉积环境为重力流沉积体系。随着B井区开发不断深入,开发矛盾逐渐突出,储层非均质性强、砂体连通性差,导致注水开发效果差,产能递减较大。为此对研究区重力流沉积特征进行研究,并结合动态开发资料分析其对油气开发的影响。B井区长6_(3)储层自上而下划分为长6_(3)^(1-1)、长6_(3)^(1-2)、长6_(3)^(2-1)、长6_(3)^(2-2)、长6_(3)^(3-1)、长6_(3)^(3-2)六个小层,研究区沉积岩石学特征和测井相分析显示,岩心上见平行层理、泥砾、火焰构造、槽模等沉积构造;长6储层为湖泊和浊流沉积,其中沉积微相划分为浊积水道、浊积水道侧翼、半深湖泥、浊积水道间4种。沉积微相平面分析显示,长6_(3)储层各小层沉积演变为一个水进到水退过程。在油气注水开发方面,由于砂体受沉积微相控制,同期砂体连通性好,注水开发效果好;砂体不同期对接式连通性差,注水开发受效差。研究结果为华庆地区油气注水开发提供了地质依据。Wellblock B of Huaqing area is located in the southwest of Ordos Basin.Chang 6_(3)reservoir is the main horizon of this wellblock,and its sedimentary environment is gravity flow sedimentary system.With the continuous deepening of development in wellblock B,the development contradictions have gradually become prominent.The reservoirs are highly heterogeneous and the connectivity of sand bodies is poor,resulting in poor waterflood development effect and large productivity decline.Therefore,the sedimentary characteristics of gravity flow in this area were studied,and their impacts on oil and gas development were analyzed in combination with dynamic development data.Chang 6_(3)reservoir in wellblock B is divided into six layers from top to bottom:Chang 6_(3)^(1-1),Chang 6_(3)^(1-2),Chang 6_(3)^(2-1),Chang 6_(3)^(2-2),Chang 6_(3)^(3-1),and Chang 6_(3)^(3-2).The characteristics of sedimentary petrology and log facies analysis in the study area show parallel bedding,mud boulder,flame structure,flute cast and other sedimentary structures on the cores.Chang 6 reservoir consists of lacustrine and turbidite deposit.The sedimentary microfacies are divided into four types:turbidite channel,turbidite channel flank,semi-deep lacustrine mud,and inter-turbidite channel.The sedimentary microfacies plane analysis shows that the sedimentary evolution of each Chang 6_(3)layer is a process of water transgression to water recession.In terms of oil and gas waterflood development,because the sand bodies are controlled by sedimentary microfacies,the connectivity is good and the waterflood development effect is good for the reservoirs of the same stage.The sand body end-to-end connectivity in different stages is poor,and the effectiveness of waterflood development is poor.The study results can provide geological basis for oil and gas waterflood development in Huaqing area.

关 键 词：长6_(3)储层 重力流 沉积微相 沉积特征 油气开发 

分 类 号：TE132.1[石油与天然气工程—油气勘探]