金山金矿构造控矿特征及其模拟实验

在前人工作的基础上,研究金山金矿构造控制产出部位,控制金山金矿蚀变糜棱岩金矿和石英脉金矿体及矿石类型,控制金山金矿微量元素、稀土元素、同位素及流体包裹体等地球化学特征;运用中国科学院地球化学研究所矿床地球化学国家重点实验室中的构造地球化学(构造成矿)高温高压实验条件进行构造控矿模拟实验,模拟高温高压条件下,岩石、矿石的变形实验,构造控制成矿物质活化、迁移聚集以及构造控制金山金矿载金矿物成矿元素变化的模拟实验和多期多次构造应力作用下成矿物质活化、迁移模拟实验。实验结果表明:构造活动的热动力作用下,不仅使岩石、矿石产生韧性剪切变形和脆性变形,并可看出韧性变形在前,脆性变形在后,并叠加在韧性变形之上,构造作用能使成矿物质活化、迁移并聚集在襁皱虚脱部位,层间破碎带及裂隙交汇部位;多期多次构造应力实验不仅使变形、破裂加剧,并使成矿物质叠加富集。实验结果与金山金矿成矿十分近似,这不仅为研究金山金矿成矿和分布规律提供实验资料和依据,也为矿区进一步找矿提供有益信息。

THE CHARACTERISTICS OF ORE-CONTROLLING STRUCTURES AND SIMULATING EXPERIMENTS OF JINSHAN GOLD DEPOSIT

In this paper,the locations of gold ore bodies controlled by tectonic structures,the locations and shape of altered mylonite-type gold ore bodies and quartz-type gold ore bodies,and the geochemical characteristics such as trace element,rare earth element(REE),isotope,and fluid inclusion are studied systematically based on previous work.Metallogenic simulating experiments which simulated the deformation of rocks and ores,the activation,mobilization and enrichment of ore-elements controlled by tectonic structures and poly-stage tectonic stress under high temperature and high pressure conditions were done at the State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences.It was indicated that rocks and ores were subjected to ductile shear deformation which happened firstly and brittle deformation which occurred after ductile shear transformation and superimposition on it under experimental conditions,the activated structures not only reinforced deformation of rocks and ores,but also provided hosting space for gold mineralization,and the activated structures may force the dispersed metallogenic materials in source rocks to be activated and to be migrated out of them as well as the accumulation of metallogenic materials and superimposition.Simulating experiments on the structural control over ore deposition provided the experimental grounds for the mechanism of formation of the Jinshan gold deposit and useful information on further ore prospecting in this area.