宁芜盆地大岭岗金铜矿床地质特征及找矿前景

Geological characteristics and prospecting potential of Dalinggang gold-copper deposit in Ningwu Basin

宁芜盆地发育一系列与火山—岩浆侵入作用有关的热液脉型金铜矿床(点),大岭岗金铜矿床属区内该类矿床。矿体主要赋存于NNW向张扭性断裂带中,呈脉状、复脉状、透镜状产出。大岭岗金铜矿床的蚀变和矿化划分为三个阶段:早期石英阶段、中期石英碳酸盐硫化物阶段和晚期石英碳酸盐重晶石阶段。大岭岗金铜矿床与燕山晚期岩浆活动有着密切的联系,岩浆发展的晚期阶段,从次火山岩(闪长玢岩)中分离出来的富含S、Cu、Fe、Co、Au等元素热液沿着断裂带及其派生的次生裂隙流向各方,与安山质火山岩中的水溶液或下渗的大气水混合,萃取地层成矿物质,使之活化转移,在有利的环境中富集成矿。大岭岗金铜矿床属次火山岩中低温热液脉型金铜矿床。大岭岗金铜矿区成矿地质背景良好,成矿条件优越,通过攻深找盲,寻找新的工业矿体的潜力巨大。

Many hydrothermal vein type gold-copper deposits related to volcanic magmatic intrusion are distributed in Ningwu basin.Dalinggang gold-copper deposit belongs to this kind of deposit in this region.The orebodies mainly occur in vein,complex vein and lens shape in NNW striking tensile shear fault zone.The alteration and mineralization of Dalinggang gold-copper deposit can be divided into three stages,early quartz stage,middle quartz carbonate sulfide stage and late quartz carbonate barite stage.Dalinggang gold-copper deposit is closely related to the late Yanshanian magmatism.In the late stage of magmatic activity,the hydrothermal solution rich in sulfur,copper,iron,cobalt,gold and other elements separate from subvolcanic rocks(diorite porphyrite)flows to all directions along the fault zone and its secondary fissures.It mixed with the aqueous solution in andesitic volcanic rocks or infiltrated atmospheric water,extracts the metallogenic materials of the strata then activates and transfers them.The mineralization is enrichedin a favorable environment.Dalinggang gold-copper deposit is a subvolcanic hydrothermal vein type gold-copper deposit.Dalinggang gold-copper deposit field has the good metallogenic geological background and superior metallogenic condition.There is a great potential to explore for new industrial ore bodies through the deep prospecting.