应力加载对花岗岩粗糙裂隙渗透率影响规律  

Effect of Stress Loading on Permeability of Granite Rough Fissure

作　　者：那金 谢康路 袁可涵 袁益龙 Na Jin;Xie Kanglu;Yuan Kehan;Yuan Yilong(Hubei Key Laboratory of Petroleum Geochemistry and Environment(Yangtze University),Wuhan 430100,China;Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University,Changchun 130021,China)

机构地区：[1]油气地球化学与环境湖北省重点实验室(长江大学资源与环境学院),湖北武汉430100 [2]吉林大学地下水资源与环境教育部重点实验室,吉林长春130021

出　　处：《地球科学》2024年第5期1810-1820,共11页Earth Science

基　　金：国家自然科学基金项目(Nos.41807194,41807208)。

摘　　要：本研究选取青海共和盆地干热岩靶区储热层印支期花岗岩为目标层,利用高压流体驱替实验装置开展岩心裂隙渗流-应力耦合下循环加卸载试验,分析应力加载过程对花岗岩粗糙裂隙渗透率影响规律,并通过数值模拟技术分析实验过程中花岗岩裂隙渗透率的演化特征.研究结果表明:(1)应力加载导致裂隙接触面产生变形,是影响裂隙渗流的主要因素,裂隙渗透率与围压呈负相关关系;(2)裂隙渗透率对不同应力加载模式敏感性存在差异;(3)在试验基础上得出数学经验公式,并通过数值模拟分析花岗岩裂隙通道内渗流演化规律,模拟结果同实验拟合较好.Selecting Indosinian granite in thermal storage layer of hot dry rock targets in the Gonghe basin,Qinghai Province,as the goal layer,using high pressure fluid displacement experiment device,the core fissure seepage and stress coupling loops and unloading test was carried out in this study.The influence law of stress loading process on granite rough fracture permeability was analyzed,and the evolution characteristics of granite fracture permeability in the experimental process were analyzed by numerical simulation technology.The results show that:(1)stress loading leads to deformation of fracture contact surface,which is the main factor affecting fracture seepage,and fracture permeability is negatively correlated with confining pressure.(2)The sensitivity of fracture permeability to different stress loading modes is different;(3)The mathematical empirical formula is obtained on the basis of the test,and the seepage evolution law in the granite fracture channel is analyzed by numerical simulation.The simulation results fit well with the experiment.

关 键 词：花岗岩 应力加载 裂隙渗透率 渗流-应力耦合 数值模拟 地热能源 

分 类 号：P641[天文地球—地质矿产勘探]