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通过金厂金矿找矿实践及采矿观察,对成矿条件及找矿方向进行研究,认为矿床的形成受构造、地层和岩浆岩三者控制。安定-九甲大断裂制约区域性超基性岩带分布,次级北西向断裂带成为晚期超基性岩侵位空间。矿床赋存于上泥盆统金厂组浅变质岩层内,为含基性火山岩组成的绿片岩相矿源层,其中硅质岩是矿床中主要赋矿的岩石类型。区内超基性岩分为早晚2期:早期超基大岩体(Σ1)的同位素年龄值302 Ma,岩体蛇纹石化、滑石化蚀变广泛,经自变质作用萃取岩体中的金,形成变质热液向有利部位转移;晚期超基性小岩体(Σ2)沿早期岩体外接触带侵位,岩浆热液活动强烈,具有成矿专属性的铬水云母化(同位素年龄值114~188 Ma)、黄铁矿化、硅化等围岩蚀变生成,并环绕小岩体分布,沿围岩构造、裂隙形成石英脉型矿体。金矿成矿经历了海底火山喷流沉积、变质作用萃取及晚期岩浆热液叠加,形成具层控和岩控特征的层-脉二元结构金矿床,其深部及外围有进一步找矿潜力。
Through the prospecting practice and mining observation of Jinchang Gold Mine, the authors studied the metallogenic conditions and prospecting direction, and believed that the formation of the deposit is controlled by the structure, strata and magmatic rocks. The stability-Jiujia large fault restricts the distribution of regional ultrabasic rocks, and the secondary north-west fault zone becomes the late ultrabasic rock emplacement space. The ore deposit is hosted in the shallow metamorphic strata of the Upper Devonian Jinchang Formation and is a greenschist facies source rock composed of basic volcanic rocks. Silicalite is the major type of ore-bearing rock in the deposit. The ultramafic rocks in the area are divided into two phases sooner or later. The isotopic age value of the early ultramafic large rock mass (Σ1) is 302 Ma. The serpentinization and talcification alteration of the rock mass is extensive. The gold in the rock mass is extracted by metamorphism , Forming metamorphic hydrothermal fluids to migrate to favorable sites. The late ultramafic small rocks (Σ2) are emplaced along the outer contact zones of early lithofacies, and the magmatic hydrothermal activity is intense with the mineralization-specific chromogenic micaization (isotopic age value 114-188 Ma), alteration of surrounding rocks such as pyrite mineralization and silicification, and the distribution of small rock mass is followed by the formation of quartz vein type ore body along the surrounding rock structure. The gold mineralization underwent submarine volcanic jet deposition, metamorphism extraction and late magmatic hydrothermal superposition to form a layer-vein dual-structure gold deposit with layer control and rock control features, with potential for further exploration in the deep and periphery.