西北地质2025，Vol.58Issue(5)：60-74,15.DOI:10.12401/j.nwg.2025070
山东平度旧店金矿床成矿物质来源和成矿模式
Sources of Ore-forming Materials and Ore-forming Model of the Jiudian Gold Deposit in Pingdu,Shandong Province
摘要
Abstract
The Jiudian gold deposit in Pingdu,Shandong Province,is located in the northwestern part of the Jiaodong gold metallogenic province and the southern segment of the Zhaoping Fault Zone.It serves as a typi-cal representative of quartz-vein type gold deposits in this region.Despite its long mining history,genetic stud-ies of this relatively small-scale deposit have remained inadequate,constraining the understanding of regional metallogenic regularity.Based on detailed field geological investigations,this study conducted hydrogen-oxy-gen isotopic analyses of quartz from ore-bearing veins and sulfur isotopic analyses of pyrite from ores,aiming to elucidate ore-forming fluid and metal sources and establish a metallogenic model for the deposit.Research indi-cates that the mineralization process of the Jiudian gold deposit can be divided into three stages:early mineral-ization stage(I),main mineralization stage(II),and late mineralization stage(III).The main mineralization stage represents the primary period of gold mineralization,further subdivided into three sub-stages:medium-coarse grained pyrite stage(II1),fine-micron fine grained pyrite stage(II2),and polymetallic sulfide stage(II3).Isotopic characteristics of quartz from different mineralization stages show:δ18OH2O=2.22‰～4.64‰ and δDV-SMOW=-90.2‰～-72.2‰ for the early stage;δ18OH2O=1.17‰～4.36‰ and δDV-SMOW=-84.3‰～-77.1‰ for the main stage;δ18OH2O=-0.01‰～4.28‰ and δDV-SMOW=-97.7‰～-87.1‰ for the late stage.The early-stage ore-form-ing fluids were predominantly magmatic water,with progressive mixing and increasing proportion of meteoric water during fluid evolution.Sulfur isotopic compositions of pyrite from different mineralization stages show no significant variation,with δ34S values ranging from 7.65‰ to 10.10‰(average 8.87‰),closely resembling the characteristics of Precambrian metamorphic basements and Mesozoic granites.Integrating previous research findings,a metallogenic model for the Jiudian gold deposit is proposed:During the Late Jurassic,remelting of gold-bearing ancient metamorphic basement rocks in the Jiudian area formed Linglong-type granites.In the Late Early Cretaceous,under the influence of large-scale lithospheric extension-thinning in the eastern North China Craton and asthenosphere upwelling,gold from granites and metamorphic rock relics underwent mobilization and enrichment.Driven by mixed fluids composed of magmatic water and meteoric water,gold precipitation oc-curred in secondary fracture structures within the footwall of the Zhaoping Fault Zone,forming the ore deposit.关键词
H-O-S同位素/成矿物质来源/成矿模式/旧店金矿床/胶东Key words
H-O-S Isotopes/source of ore-forming materials/ore-forming model/Jiudian gold deposit/Jiaodong分类
天文与地球科学引用本文复制引用
吴明刚,范德江,钟世华,邱敦方,宋子崇,田福泉,吕鹏瑞,许道学,牛警徽,Rahnama Zohreh,张永林..山东平度旧店金矿床成矿物质来源和成矿模式[J].西北地质,2025,58(5):60-74,15.基金项目
国家自然科学基金面上项目"基于多维数据的斑岩Cu矿床成矿岩浆机器学习识别方法和矿床成因研究"(42472104)资助. （42472104）
