孔喉结构对超深层碳酸盐岩气藏多类型储层渗流能力的影响  

Effect of pore throat structure on flow capacity of multi-type ultra-deep carbonate gas reservoirs

作　　者：张钰祥 闫海军[1] 位云生[1] 曹正林[1] 郭建林[1] 杨胜来 邓惠[3,4] 陈掌星 郑国强[1] 王忠楠[1] ZHANG Yuxiang;YAN Haijun;WEI Yunsheng;CAO Zhenglin;GUO Jianlin;YANG Shenglai;DENG Hui;CHEN Zhangxing;ZHENG Guoqiang;WANG Zhongnan(Research Institute of Petroleum Exploration&Development,PetroChina,Beijing 100083,China;State Key Laboratory of Petroleum Resources and Exploration,China University of Petroleum(Beijing),Beijing 102249,China;PetroChina Southwest Oil and Gas Field Company,Chengdu 610051,China;Sichuan Petroleum Administration Co.,Ltd.,Chengdu 610051,China;Department of Chemical and Petroleum Engineering,University of Calgary,Calgary T2N1N4,Canada)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]中国石油西南油气田分公司,四川成都610051 [4]四川石油管理局有限公司,四川成都610051 [5]加拿大卡尔加里大学化学与石油工程系,卡尔加里T2N1N4

出　　处：《中国石油大学学报（自然科学版）》2024年第4期131-140,共10页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：中国石油天然气有限公司科技项目(2023YQX10501,2023YQX10503ZK);四川省自然科学基金项目(2023NSFSC0261)。

摘　　要：超深层碳酸盐岩气藏孔喉结构非均质性强,渗流机制复杂。选取川西北地区双鱼石区块栖霞组储层岩心,通过多尺度CT试验、核磁共振试验和储层条件下的单相渗流、气水两相渗流及应力敏感试验等,系统定量地研究超深层多类型储层孔喉结构特征参数与渗流特征参数的相关性,深入剖析裂缝、大孔和基质孔隙对超深层多类型气藏气体单相和气水两相渗流的影响。结果表明:不同于中深层储层,增加喉道数量对于提高目的超深层储层的渗流能力非常关键;裂缝发育增加了岩样喉道数量、提高了岩样的连通性从而来大幅度提高岩样的气体渗流能力,并降低了含水气藏的启动压力梯度,缩小了岩样的气水两相共渗区间,但裂缝受压易形变的特质导致岩样的应力敏感性增强,在高压差时岩样的渗流能力和弹性能也急速下降;大孔喉发育提高了储层的储容能力,其抵抗变形能力强的特质有利于降低岩样的应力敏感性,在高压差时维持岩样较高的渗流能力和弹性能。在实际生产过程中,应考虑对裂缝-孔隙型和裂缝-孔洞型储层在生产初期控制产气速度以维持长期稳产,对孔洞型和孔隙型储层增大生产压差或进行压裂和酸化等工艺措施以释放储层产能。The pore-throat structure of ultra-deep carbonate gas reservoirs is highly heterogeneous,and its flow mechanism is complex.In this study,rock samples of the Qixia Formation in the Shuangyushi block in the Northwest Sichuan Basin were selected,and various methods were used for core analysis and flow experiments,including multi-scale CT,nuclear magnetic resonance,stress-sensitivity,elastic energy testing under reservoir conditions,single-phase flow and gas-water two-phase flow.The relationship between the characteristic parameters of pore-throat structure and the characteristic parameters of flow in the ultra-deep multi-type reservoir were systematically and quantitatively investigated,and the influences of fractures,macropores and matrix pores on single-phase and two-phase flow were analyzed.The results show that,different from medium-deep reservoirs,increase of the throat number is critical to the improvement of the flow capacity of the targeted ultra-deep reservoir.Development of fractures can greatly improve gas flow capacity of the rock samples by increasing the throat number of and improving the pore connectivity,which can reduce the threshold pressure gradient of water-bearing gas reservoirs,and shrink the gas-water two-phase copermeability interval.However,the stress sensitivity of the rock sample can be enhanced,and its flow capacity and elastic energy decrease rapidly under high pressure difference due to the characteristics of the fractures that can be easily deformed under pressure.Development of large pores or throats can improve the storage capacity of the reservoir,and their strong resistance to deformation is beneficial to reduce the stress sensitivity of rock samples,which can maintain high flow capacity and elastic energy of the rock samples under high pressure difference.In the actual production process,it should be considered to control the gas production rate for fracture-porous type and fracture-cavity type reservoirs in the early stage of production in order to maintain long-term stable gas p

关 键 词：超深层气藏 栖霞组 碳酸盐岩 渗流机制 缝洞结构 相关性分析 

分 类 号：TE311[石油与天然气工程—油气田开发工程]