海洋地质前沿2026，Vol.42Issue(5)：23-36,14.DOI:10.16028/j.1009-2722.2025.160
涠西南凹陷流三段辫状河三角洲沉积演化特征与有利储层分析
Sedimentary evolution and favorable reservoir analysis of braided river delta in the third member of Liushagang Formation in the Weixi'nan Sag
摘要
Abstract
The development characteristics of continental sedimentary systems and the prediction of favorable reservoirs during the rifting period in the Weixi'nan Sag are key issues of research for hydrocarbon exploration in this area.Taking the third member of the Liushagang Formation(Liu-3member)in the Weizhou A Block as an ex-ample,we integrated sedimentology and diagenesis analyses to reveal the evolution patterns of sedimentary sys-tems and the main controlling factors on favorable reservoirs.Results show that during the deposition period of the Liu-3 member,braided river delta deposits controlled by mainly a transfer zone were developed in the study area,and 4 types of sedimentary microfacies were recognized:subaqueous distributary channels,interdistributary bays,mouth bars,and sheet sands.The evolution progresses went through three stages:development,flourishing,and decline,and the sand bodies reached the climax during the flourishing stage.The reservoirs are predomin-antly low-porosity and low-permeability quartz sandstones,with secondary dissolution pores constituting the dom-inant reservoir space.Quantitative evaluation results clearly indicate that favorable reservoirs were formed in two mechanisms:the sedimentary facies was the primary factor on the matrix properties and the diagenetic facies was the secondary that modified the reservoir rocks;and subaqueous distributary channels exhibit optimal physical properties,while dissolution is the primary constructive diagenetic process.By analyzing the coupling of geolo-gical and geophysical factors,we predicted that the sand bodies in the main area of the subaqueous distributary channels in the delta front will develop the most favorable reservoirs with higher exploration potential.The find-ings provided a theoretical foundation for future hydrocarbon exploration and development in continental lake basins.关键词
涠西南凹陷/流沙港组/辫状河三角洲/沉积演化/成岩作用/有利储层预测Key words
Weixi'nan Sag/Liushagang Formation/braided river delta/sedimentary evolution/diagenetic pro-cess/favorable reservoirs prediction分类
海洋科学引用本文复制引用
陈岳,张道军,孙文钊,黄灿,左倩媚,招湛杰,张建新,徐守立..涠西南凹陷流三段辫状河三角洲沉积演化特征与有利储层分析[J].海洋地质前沿,2026,42(5):23-36,14.基金项目
中国海洋石油有限公司科研项目(KJZH-2024-2106) （KJZH-2024-2106）
