陕西省钨钼多金属矿床时空分布规律及找矿方向

Temporal-spatial Distribution and Prospecting Direction of W-Mo Polymetallic Deposit in Shaanxi Province

陕西省横跨华北陆块、秦岭—大别造山带和扬子陆块三大主要构造单元,钨钼矿产于陕西南部的秦岭造山带中,其构造位置独特,成矿条件优越,钼矿资源丰富,钨矿资源找矿潜力大。通过对陕西省钨钼多金属矿床时空分布规律及找矿方向进行研究,结果表明:钨钼矿床(点)的形成与分布严格受印支—燕山期陆内构造岩浆岩带控制,印支期近EW向与燕山期NNE—近SN向两组构造组成的"格子状"交汇部位,即为最有利的钨钼成矿区域,中酸性大岩体(基)旁侧的小岩体(岩脉群)是控制钨钼矿形成与分布的重要条件,具有"小岩体成(大)矿"特点。钼矿床类型以斑岩型、岩浆热液脉型和接触交代型为主,钨矿床类型以岩浆热液脉型和接触交代型为主。钼矿成矿时代主要集中在印支—燕山期及燕山期,而钨矿主要集中在燕山期与喜马拉雅期。在秦岭造山带内,沿NE向中生代构造—岩浆岩带形成了金堆城—黄龙铺、蟒岭西部和镇安西部—宁陕旬阳坝等3个重要的钨钼矿集区,进一步划分出了蓝田—八里坡钼矿、蟒岭西部钼矿、杨斜钨矿、蔡家庄—杨木沟钨钼矿、大菜子沟—大西沟钨钼矿等5个找矿远景区。建议灵活运用"小岩体成(大)矿"理论,并充分借鉴南岭地区先进、成熟的"上脉下体、上钨下钼"、"五层楼"或"五层楼+地下室"找矿模式,在矿集区及周边的找矿远景区开展新一轮的钨钼找矿工作,有望取得重大突破。

Shaanxi Province straddles three main tectonic units of North China Block,Qinling-Dabie orogenic belt and Yangtze block.It has unique structural location,superior metallogenic conditions,rich molybdenum resources and great potential of tungsten resources.Through the study on the temporal-spatial distribution and prospecting direction of W-Mo polymetallic deposit in Shaanxi Province,the results show that the formation and distribution of tungsten and molybdenum deposits(spots)are strictly controlled by Indosinian and Yanshanian intracontinental tectonomagmatic belt.The most favorable tungsten and molybdenum metallogenic area is the lattice intersection of Indosinian nearly EW trending and Yanshanian NNE nearly SN trending structures.The small rock mass(dyke group)on the side of medium acid large rock mass(base)is an important condition to control the formation and distribution of W-Mo deposit,which is characterized by small rock mass forming(large)deposit.The main types of molybdenum deposits are porphyry type,magmatic hydrothermal type and contact metasomatic type,while the main types of tungsten deposits are magmatic hydrothermal vein type and contact metasomatic type.Molybdenum deposits are mainly concentrated in Indosinian-Yanshanian and Yanshanian,while tungsten deposits are mainly concentrated in Yanshanian and Himalayan.There are three important tungsten and molybdenum ore concentration areas in the Qinling orogenic belt along the NE trending Mesozoic tectonic magmatic belt,namely Jinduicheng-Huanglongpu,Mangling West and Zhen’an West-Xunyangba of Ningshan Area.It is further divided into five ore prospecting prospect area,including Lantian-Balipo Molybdenum Deposit,Mangling West Molybdenum Deposit,Yangxie Tungsten Deposit,Caijiazhuang-Yangmugou W-Mo Deposit and Dacaizigou-Daxigou W-Mo Deposit.It is suggested to carry out a new round of W-Mo deposit prospecting work in the ore concentration area and the surrounding prospecting prospect areas expecting to make a major breakthrough,which based on flexibly using the theory of"small rock mass forming(large)ore"and fully learning from the advanced and mature prospecting models of"upper vein and lower body,upper tungsten and lower molybdenum","five storey building"or"five storey building+basement"in Nanling Area.