胶东大尹格庄金矿床成矿过程数值模拟及其找矿意义  

Numerical Simulation of Metallogenic Processes of Dayingezhuang GoldDeposit in Jiaodong Peninsula and Its Prospecting Significance

作　　者：单文法[1,2,3,4] 毛先成 刘占坤[2,3] 邓浩[2,3] 陈进 张维[2,3,5] 王海正[6] 杨鑫[6] SHAN Wenfa;MAO Xiancheng;LIU Zhankun;DENG Hao;CHEN Jin;ZHANG Wei;WANG Haizheng;YANG Xin(Computational Geosciences Research Centre,Central South University,Changsha 410083,Hunan,China;School of Geosciences and Info-Physics,Central South University,Changsha 410083,Hunan,China;Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring,Ministry of Education,Central South University,Changsha 410083,Hunan,China;Hunan Mass Media Vocational and Technical College,Changsha 410100,Hunan,China;School of Municipal and Geomatics Engineering,Hunan City University,Yiyang 413099,Hunan,China;Zhaojin Mining Industry Co.,Ltd.,Zhaoyuan 266009,Shandong,China)

机构地区：[1]中南大学计算地球科学研究中心,湖南长沙410083 [2]中南大学地球科学与信息物理学院,湖南长沙410083 [3]中南大学有色金属成矿预测与地质环境监测教育部重点实验室,湖南长沙410083 [4]湖南大众传媒职业技术学院,湖南长沙410100 [5]湖南城市学院市政与测绘工程学院,湖南益阳413099 [6]招金矿业股份有限公司,山东招远266009

出　　处：《黄金科学技术》2023年第5期707-720,共14页Gold Science and Technology

基　　金：国家自然科学基金重点项目“矿床时空结构定量表征与智能理解”(编号:42030809);湖南省自然科学基金青年项目“不确定性随机扰动下的三维成矿预测与风险评估”(编号:2022JJ40022)联合资助。

摘　　要：大尹格庄金矿床的形成涉及到构造变形、流体活动、热量传递和水岩反应等过程的相互耦合作用。利用FLAC3D数值模拟软件,结合现代矿化率概念,开展了大尹格庄金矿床力—热—流—化耦合的数值模拟,以探讨断裂、体积形变与化学过程耦合对金矿体就位的控制作用。研究结果表明:正体积应变、流体汇聚和金析出量(负矿化率)的高值区均位于控矿招平断裂倾角由陡倾向缓倾转换部位以及断裂局部起伏部位,与金矿体的实际空间分布相吻合,反映出成矿流体更多地汇聚、停留在这些部位,并发生强烈的化学反应,引起金的沉淀析出。这种多物理—化学过程在相同部位的耦合可能是控制大尹格庄金矿床形成的关键因素,基于该成矿规律,推测大尹格庄金矿区深部具有较大的成矿潜力。The formation of the Dayingezhuang gold deposit involves the coupled effects of tectonic deformation,pore-fluid transport,heat transfer,and hydrogeochemical reactions.In this paper,FLAC3D numerical simulation software and modern mineralization rate concept were used to carry out numerical simulation of force-heat-fluid-chemical coupling of Dayingezhuang gold deposit,so as to explore the controlling effect of fracture structure,bulk deformation,and chemical process coupling on the emplacement of gold orebody.The simulation results demonstrate the following findings:From the perspective of physical process,the steep-slow transition and its local undulation zones along the Zhaoping fault tend to develop larger volume strains with differences of up to 1%compared to the surrounding rocks.This uneven strain distribution leads to the formation of uneven ore-holding spaces and pore pressure variation distribution.Significantly differences between high values of positive and negative pore pressure gradients are observed near the zones with large volume strains,while the differences in other zones are less notable.From the perspective of chemical process,mineralizing fluids tend to converge and stagnate at sites with high volume strain during their migration from the deep to the shallow parts.This convergence of mineralizing fluids leads to a greater precipitation of gold orebodies(mineralization rate less than 0),indicating the occurrence of intense water-rock reactions.In contrast,the areas where the mineralizing fluids don’t converge exhibit a predominance of positive mineralization rate distribution,suggesting the absence of significant gold orebody precipitation.Furthermore,the ROC curve analysis with an AUC value of 0.815 provides quantitative evidence of the strong correlation between the mineralization rate and known gold orebodies,suggesting that this coupling of multiple physical-chemical processes at the same sites may be a key factor governing the formation of Dayingezhuang gold deposit.Based on these observa

关 键 词：蚀变岩型金矿 数值模拟 成矿流体 控矿因素 矿化率 大尹格庄金矿床 

分 类 号：P618.51[天文地球—矿床学]