小秦岭地区金钼多金属矿成矿特征与找矿预测  

Metallogenic Characteristics and Exploration Prediction of Au-Mo Polymetallic Deposits in Xiaoqinling Area

作　　者：王瑞廷[1,2] 袁海潮 孟德明[1] 王磊 马文平 

机构地区：[1]长安大学地球科学与资源学院,陕西西安710054 [2]西北有色地质勘查局地质勘查院,陕西西安710054 [3]西北有色地质勘查局712总队,陕西咸阳712000

出　　处：《地球科学与环境学报》2014年第1期19-31,共13页Journal of Earth Sciences and Environment

基　　金：国土资源部公益性行业科研专项项目(201111007-3);"十二五"国家科技支撑计划项目(2011BAB04B05)

摘　　要：小秦岭地区是中国重要的金钼矿产基地。以构造岩浆成矿系统为指导，综合研究认为区内金钼多金属矿床可分为印支期-燕山期与重熔型花岗岩浆侵入活动有关的金（钼）矿床成矿系列和与深源浅成型花岗岩、碱性岩有关的钼（金钨）矿床成矿系列。金（钼）矿床类型主要包括石英脉型、构造蚀变岩型、糜棱岩型、爆破角砾岩型和复合型等，以前两者为主；钼（金钨）矿床类型主要包括斑岩型、斑岩矽卡岩型、斑岩爆破角砾岩型、石英碳酸岩脉型和构造蚀变岩型等，也以前两者为主。该区三叠世以来共发生过3次岩浆侵入活动，每次都伴有不同程度的钼金矿化作用，并分别对应于不同的钼金矿化高峰期。钼的成矿作用分为印支期（210～220 Ma）和燕山期早白垩世早期（140～145 Ma）、早白垩世中晚期（110～138 Ma）；金的成矿作用分为印支期（约220 Ma）和燕山期早白垩世中晚期（约130 Ma）；钼、金成矿在印支期和燕山期早白垩世中晚期叠合，而在燕山期早白垩世早期分离。整体上，区内岩体与断裂构造控矿特征明显，燕山期金钼成矿作用强烈发育。该区娃娃沟-峪耳沟、峪耳沟-曹家沟、太子坪-葫芦沟-荒地沟与文公岭北坡等地区为金钼多金属矿的有利找矿靶区，并应特别重视中酸性小岩体的含矿性评价。Xiaoqinling area is an important Au-Mo mineral base in China.Based on the tectonic-magmatic-metallogenic system,the Au-Mo polymetallic deposits in Xiaoqinling area can be divided into two metallogenic series：Au （Mo）deposits related to remelting granite magmatic intrusion,and Mo （Au-W）deposits related to deep-hypabyssal granites and alkaline rocks in Indosinian-Yanshanian.The main types of Au （Mo）deposits include quartz vein,structural altered rock-host,mylonite, explosive breccia,composite rock,etc.,and the first two types are predominant.The main types of Mo （Au-W）deposits include porphyry,porphyry-skarn,porphyry-explosive breccia,quartz-carbonate vein,structural altered rock-host,etc.,and the first two types are also predominant. There are three magmatic intrusion activities accompanied by different degrees of Mo-Au＆amp;nbsp;mineralization since Triassic,corresponding to three different peaks of Mo-Au mineralization.Mo mineralization epoch includes Indosinian （210-220 Ma）,the early stage of Early Cretaceous （140-145 Ma） and the middle-late stage of Early Cretaceous （110-138 Ma） in Yanshanian;Au mineralization epoch includes Indosinian （about 220 Ma）and the middle-late stage of Early Cretaceous in Yanshanian （about 130 Ma）;Mo and Au mineralizations coincide in Indosinian and the middle-late stage of Early Cretaceous in Yanshanian,but separate in the early stage of Early Cretaceous in Yanshanian. Characteristics of intrusion and fault tectonic ore-controlling are obvious,and Au-Mo mineralization in Yanshanian is strong in Xiaoqinling area as a whole.The favorable prospecting targets for Au-Mo polymetallic in Xiaoqinling area are Wawagou-Yu＆#39;ergou, Yu＆#39;ergou-Caojiagou, Taiziping-Hulugou-Huangdigou and the northern slope of Wengongling,and the ore-bearing potential evaluation of intermediate-acid small intrusion should be paid attention to.

关 键 词：金钼矿床 成矿特征 中酸性岩体 印支期-燕山期 找矿标志 找矿预测 小秦岭地区 

分 类 号：P588.3[天文地球—岩石学]