甘肃龙尾沟斑岩型铜(钨)矿床成矿特征及形成环境  

Geological Characteristics and Metallogenic Environment of the Longweigou Porphyry Copper(tungsten) Deposit,Gansu

作　　者：贾群子[1] 马云海[2] 全守村[1] 王建军[2] 肖朝阳[1] 李金超[1] 

机构地区：[1]西安地质矿产研究所,西安710054 [2]甘肃省地质调查院,兰州730000

出　　处：《矿物岩石地球化学通报》2012年第6期599-605,共7页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：青藏高原地质矿产调查与评价专项(1212011121205);国土资源大调查项目(200420190002)

摘　　要：龙尾沟铜(钨)矿床是祁连山地区新近发现的一处斑岩型矿床,其评价及研究对祁连山地区铜矿勘查具有重要的指导和借鉴作用。本文通过对含矿斑岩年代学及地球化学、矿体产出特征及矿石物质组成、围岩蚀变等进行了系统研究,结果表明,花岗闪长斑岩形成年龄为358.7Ma;矿体呈似层状、透镜状和脉状产出,主要产于高钾碱性系列斑岩体内,并受近南北向构造控制;矿石矿物主要为黄铜矿、黄铁矿、磁黄铁矿、白钨矿,呈细脉-浸染状、浸染状产出;矿化以富铜、钨、金贫钼为特征;与成矿关系密切的围岩蚀变主要为绢英岩化,次为钾硅酸盐化和硅化;矿床成矿时代为海西早期,形成于陆内造山伸展环境。从成矿背景分析认为祁连山地区陆内造山环境所形成的斑岩型铜矿具有良好的找矿前景。The Longweigou porphyry copper（tungsten） deposit,a newly found deposit,lies in the Oulongbuluke uplift belt of the Qilian orogenic belt.The evaluation and research of the Longweigou copper（tungsten） ore deposit will present important guidance and reference for copper exploration in the Qilian Mountain area.The chronology and the geochemistry of the ore-bearing porphyry deposit were studied and the occurrence features of the deposit,the components of gold mineral and the alteration of the wall rock were investigated.Results showed that the formation age of the granodiorite porphyry is 358.7Ma;and that the ore-body,which has occurrences of stratiform or lenticular or vein,occurs mainly in the high potassium alkali series porphyry and is controlled by NS structures;and that chalcopyrite,pyrite,pyrrhotite,and scheelite are main ore minerals,which have veinlet-disseminated and disseminated structures;and that mineralization is characterized by enriching copper,tungsten and gold and depleting molybdenum;and that the mineralization related wall-rock alterations are mainly sericitization and secondly potassium-silicate alteration and silisification;and that the metallogenic epoch is the early Variscan and the deposit was formed in the inner-continental oregenic extension setting.On the basis of the above finds,we believe that the porphyry copper deposit,which formed the intra-continent orogeny of the Qilian area,has excellent prospecting potential.

关 键 词：斑岩型铜(钨)矿床 成矿特征 形成环境 龙尾沟 欧龙布鲁克 

分 类 号：P618.41[天文地球—矿床学] P618.67[天文地球—地质学]