D气田群黄流组一段CO_2对储层质量的影响  

Effect of CO_2 on Reservoir Quality in Huang-1 Member of Huangliu Formation in D Gasfield Group

作　　者：甘永年 叶青 漆智 郇金来 吴倩 Gan Yongnian;Ye Qing;Qi Zhi;Huan Jinlai;Wu Qian(Zhangjiang Branch Company,CNOOC,Zhanjiang Guangdong 524057,China)

机构地区：[1]中海石油(中国)有限公司湛江分公司,广东湛江524057

出　　处：《地质科技情报》2018年第4期141-145,共5页Geological Science and Technology Information

基　　金：国家科技重大专项"莺琼盆地高温高压天然气富集规律与勘探开发关键技术"(三期)(2016ZX05024-005)

摘　　要：综合利用气体组分分析、铸体薄片分析、孔隙定量分析及常规物性分析等手段,对CO_2-地层水-砂岩的反应机理进行了研究。结果表明:早期CO_2溶于水形成碳酸,使得骨架颗粒及早期胶结物溶解形成大量的孔隙,晚期过量的H+消耗使得溶液呈碱性,下伏热流体所携带的HCO_3^-和CO_2水解形成的HCO_3^-与早期地层中的Mg^(2+)、Fe^(2+)化合形成碳酸盐胶结物,以铁白云石为典型代表,在碱性环境下进行沉淀堆积,堵塞孔隙及喉道,综合早期建设性成岩作用及晚期破环性成岩作用,最终降低了储层质量,尤其在CO_2体积分数大于10%时表现最为明显。This paper studies the reaction mechanism of CO2-formation water-sandstone by using gas composition data,rock thin sections,and quantitative analysis of pore and regular physical properties.Results show that：in the early period,CO2 dissolves in water to form carbonate,causing the skeleton particles and the early cement to dissolve and form a large number of pores.While in the later period,excessive H＋depletion makes the solution alkaline,and leads HCO3^-- carried by the downward heat flow and CO2 hydrolysis and Mg^2＋,Fe^2＋ formed in early strata to form carbonate cement,with iron dolomite as a typical representative.The iron dolomite is accumulated in alkaline environment and block the pore and throat,finally,reduces the reservoir quality by combining with the early constructive diagenesis and late destructive diagenesis.This is especially obvious when CO2 content is greater than 10%.

关 键 词：莺歌海盆地 CO2 黄流组一段 储层质量 铁白云石 

分 类 号：P618.130.21[天文地球—矿床学]