内蒙古额仁陶勒盖银矿床成岩成矿模式

DIAGENIC-METALLOGENIC MODEL OF ERENTAOLEGAI SILVER DEPOSIT IN INNER MONGUOLIA

地质、地球化学研究表明 :额仁陶勒盖银矿床是次火山热液作用产物。燕山晚期本区受太平洋板块边缘的影响 ,在已存断裂复活的条件下 ,产生壳幔混合作用形成花岗质岩浆 ,该岩浆在地下浅处发生强烈的结晶分异作用形成花岗岩和石英斑岩 ,两者是同一岩浆不同成岩阶段的产物 ,石英斑岩是成岩阶段的最后产物 ,分异作用导致银在成岩后期及期后成矿热液中富集。矿床地质地球化学证据表明石英斑岩是矿床的直接母岩。地表大气水对成矿有下列作用 :(1)有助于发生基底岩石的部分熔融 ;(2 )有利于形成大量的矿液。

By studying the geology and geochemistry about the ore deposit and granite,it is clear that Erentaolegai silver deposit is the product of subvolcanic hydrothermal genesis.The local area was edge-subjected to the movement in later Yanshan.The fault which had been exited was revive,brought about crust-mantle granite magma.The magma gave rise to crystallization differentiation;formed granite and quartz porphyry.The quartz porphyry is the product of violent granite magma crystallization differentiation,so forth the silver was in rich in the later diagenetic stages and post-diagenetic ore solution.Quartz porphyry is parent rock of the are deposit.Meteorological water on earth's surface pays an important role to form the magma and deposit:(1)Contributing to magma crystallization differentiation,and bringing to the silver in rich in quartz porphyry magma;(2)Contributing to form a great of quantities ore solution.