福建吉花金银矿床地质特征及含矿蚀变带元素迁移对区域成矿的启示  

Geological characteristics of Jihua Gold-Silver Deposit in Fujian and implications of element migration in the ore-bearing alteration zone for regional mineralization

作　　者：王俊德 汤立伟 杜庆安[1] 黄卫强 侯海峰[1] 陈文庆 鲁涛峰 Wang Junde;Tang Liwei;Du Qing'an;Huang Weiqiang;Hou Haifeng;Chen Wenqing;Lu Taofeng(The Second Geological Exploration Institute of CMGB;No.2 Geological Team of Henan Provincial Bureau of Geology and Mineral Resources)

机构地区：[1]中国冶金地质总局第二地质勘查院 [2]河南省地质矿产开发局第二地质勘查院

出　　处：《黄金》2024年第3期55-66,共12页Gold

基　　金：中国地质调查局项目(D220030);中国冶金地质局项目(202102010)。

摘　　要：吉花金银矿床为中型浅成中低温热液型矿床,共圈定36个金银矿体,均赋存于北东向断裂蚀变带中。银物相分析表明,银以硫化物银、自然银为主,银、金总体上同体共生,且二者品位具有正相关性。主成矿阶段矿物组合以石英-黄铁矿-黄铜矿-金-辉银矿为特征。沿矿体横向(侧向)划分为4个蚀变分带。为了厘定热液蚀变过程中的物质迁移,对蚀变碎裂岩采用标准化Isocon图解法计算物质迁移特征,结果表明,蚀变过程中Fe、Si、Mg、Ti、Cu、As、Mo、Co、Cr、La、Li、Ni、V呈迁入特征;Na、Ca、Ba、Sr、Nb呈迁出特征,其中Ca、Ba、Sr的迁出表明成矿热液具有富硅、去钙化的特征。通过类比区域内邱村金矿床、东洋金矿床、大冬坑金矿床,四者均为闽中金银成矿系统形成的矿床系列,可能是在古太平洋板块俯冲、后撤动力背景下,含矿流体沿火山机构及酸性岩脉通道运移至到浅部断裂中沉淀成矿的区域成矿模式。该成果可为区域内寻找金银矿提供思路。A total of 36 gold-silver ore bodies have been delineated in the Jihua medium-scale shallow medium-low temperature hydrothermal gold-silver deposit,all of which occur in the NE fault structural alteration zone.Silver physical phase analysis shows that silver is mainly composed of silver sulfide and native silver.Silver and gold are generally coexisting in the same body,and both grades are positively correlated.The mineral assemblage of the main mineralization stage is characterized by quartz-pyrite-chalcopyrite-gold-silverite.4 alteration zones were divided along the horizontal(lateral)direction of the ore body.In order to determine the material migration during hydrothermal alteration,the standardized Isocon diagram method was used to calculate the material migration characteristics of altered fractured rocks.The results showed that Fe,Si,Mg,Ti,Cu,As,Mo,Co,Cr,La,Li,Ni,and V showed immigration characteristics during the alteration process;Na,Ca,Ba,Sr,and Nb migrated out.The emigration of Ca,Ba,and Sr indicates the cha-racteristics of silicon-rich and decalcified ore-forming hydrothermal fluids;by analogy with the previous research results of Qiucun Gold Deposit,Dongyang Gold Deposit,and Dadongkeng Gold Deposit in the same area,the 4 deposits are all formed by the gold and silver metallogenic system in central Fujian.They may be the regional metallogenic model of the subduction and retreat of the ancient Pacific plate,the migration of ore-bearing fluid along the volcanic mechanism,and acid dike channel to the shallow fault zone to precipitate mineralization.The research can provide ideas for the search for gold-silver deposits in the region.

关 键 词：吉花金银矿床 矿床地质特征 标准化Isocon图解 蚀变分带 元素迁移 区域成矿模式 

分 类 号：TD11[矿业工程—矿山地质测量] P618.51[天文地球—矿床学]