紫金山矿集区花岗岩“原地重熔”成矿模式探讨  

Discussion on the Metallogenic Model of Granite“In-Situ Melting”in Zijinshan Mineralization Area

作　　者：阮诗昆 曾文灿[2] 

机构地区：[1]福州大学紫金矿业学院,福州350108 [2]紫金矿业集团股份有限公司,福建上杭364200

出　　处：《地质科技情报》2014年第6期170-174,179,共6页Geological Science and Technology Information

基　　金：国家科技支撑计划课题(2009BAB43B04)

摘　　要：传统地质学理论认为花岗岩是由异地深熔的花岗岩浆沿构造侵入至地壳浅部冷凝结晶形成的,"原地重熔-壳内对流"理论认为熔融的花岗岩浆并没有离开源区,而是原地重熔,熔融岩浆层内的热能对流形成大规模层状或似层状花岗岩浆,岩浆层冷凝结晶形成花岗岩,花岗岩体是岩浆层界面(MI)凸起形成的。燕山晚期花岗闪长斑岩是紫金山矿集区成矿母岩,在温度差和压力差作用下,成矿元素和挥发分在MI凸起界面上部富集形成含矿流体,在沿构造裂隙向上向外逃逸过程中与围岩产生水岩反应,形成从高温到低温热液蚀变分带,而不同成矿元素则在不同温度、压力(深度)和Eh、pH区间沉淀成矿,形成罗卜岭斑岩型铜钼矿、紫金山高硫化中低温热液型铜金矿和悦洋低硫化低温热液型银多金属矿,它们是同一斑岩-浅成热液成矿体系的产物。The traditional geology theory shows that granite is the formation of magma condensation crystallization which is from off-site anatectic magma to the shallow crust along the tectonic.The ＂In-Situ Melting and Crustal Evolution＂theory presents that the molten granite does not leave the source region and is in-situ remelting.Thermal convection in the molten magma layer forms large-scale layered or bedded granite magma and granite is the formation of condensation crystallization of the magma layer.The granite pluton is the formation of the bugle of magma interface（MI）.Granodiorite-porphyrrite of late Yanshanian is mineralization host rock in the ore cluster area.Under different temperature and pressure,the ore-forming elements and volatiles accumulate at the upper MI and generate the ore-forming fluids,which produce water-rock reactions with rock in the outward escape process along the tectonic and cause the hydrothermal alteration zonation comes into formation from high temperature to low temperature.The different oreforming elements are the formation of mineralization in different temperature,pressure（depth）,Eh,and pH range.The Luoboling porphyry Cu-Mo deposits,Zijinshan high sulfidation epithermal Cu-Au deposits,and Yueyang low sulfidation epithermal silver metallic minerals deposits,are all the product of the same porphyry-epithermal mineralization systems.

关 键 词：紫金山 原地重熔 岩浆界面凸起 斑岩-浅成热液成矿体系 

分 类 号：P611[天文地球—矿床学]