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上房钨矿床是武夷山成矿带新近发现的大型白钨矿矿床,也是福建省发现的钨矿新类型.矿床产于上房似斑状黑云母正长花岗岩体的外接触带上,赋矿围岩主要为古元古代大金山岩组斜长角闪岩和黑云斜长变粒岩,矿体产状与围岩的片理一致,矿石类型为石英细脉型和浸染型,金属矿物主要为白钨矿和辉钼矿,其次为少量磁黄铁矿、黄铁矿和黄铜矿等.野外地质观察和矿化特征研究表明,上房钨矿的矿床类型为接触交代型.采用LA-ICP-MS锆石U-Pb和辉钼矿Re-Os测年技术,对与成矿有关的上房似斑状黑云母正长花岗岩和与白钨矿共生的辉钼矿进行成岩成矿年代测定,获得上房似斑状正长花岗岩体的成岩年龄为158.8±1.6Ma(1σ),辉钼矿Re-Os模式年龄为159.40±0.86～149.92±1.39Ma(n=5),模式年龄的加权平均值为156.5±4.0Ma,等时线年龄为158.1±5.4Ma(2σ).同位素定年结果表明,上房钨矿床与矿区似斑状黑云母正长花岗岩关系密切,二者均形成于晚侏罗世,与华南地区中生代大规模钨多金属矿床的成矿时代一致.传统观点认为,华南地区晚侏罗世(160～150Ma)钨多金属矿床大规模成矿作用集中于南岭成矿带中东段的湘南、粤北和赣南地区,而本文的研究结果则说明这一区域成矿作用向北东延伸进入到武夷山成矿带的闽西和闽北地区.因此,华南钨多金属矿床的空间分布不是传统认为的近东西向,而是具有北东向或北东东向展布的特点,是滨太平洋构造-岩浆-成矿域的重要组成部分.
The Shangfang tungsten deposit is a large-scale scheelite deposit recently discovered in the Wuyishan metallogenic belt and also a new type of tungsten ore discovered in Fujian Province. The deposit was produced on the outer contact zone of the granitic boulder-like biotite granite body, The rocks are mainly Paleoproterozoic Daijishanyan amphibolite and biotite plagiogranulite. The occurrence of the orebody is consistent with that of the surrounding rock. The types of the ore are quartz veins and disseminated types, and the metal minerals are mainly For the scheelite and molybdenite, followed by a small amount of pyrrhotite, pyrite and chalcopyrite, etc. Field geological observation and mineralization characteristics of the study shows that the Shangfang tungsten deposit type contact with the exchange of type.Using LA -PIC-MS zircon U-Pb zircon and Re-Os dating of molybdenite, the diagenetic and ore-forming ages of ore-forming macrophytic biotite-bearing granite and molybdenite coexisting with scheelite The diagenetic age of the granite body is 158.8 ± 1.6Ma (1σ) and the molybdenite Re-Os age is 159.40 ± 0.86 ~ 149.92 ± 1.39Ma (n = 5) The average is 156.5 ± 4.0Ma and the isochron age is 158.1 ± 5.4Ma (2σ). The isotopic dating shows that the Shangfang tungsten deposit is similar to the mine The monzogranite is closely related to granitoids, both of which formed in the Late Jurassic and coincided with the metallogenic epoch of the Mesozoic large-scale tungsten polymetallic deposits in South China. The traditional view is that the Late Jurassic (160 ~ 150 Ma) The large-scale mineralization of tungsten polymetallic deposits concentrates in southern Hunan, northern Guangdong and southern Jiangxi in the middle and east parts of the Nanling metallogenic belt. However, the results of this study show that the mineralization in this area extends northward into Wuyishancheng The ore belt is in western Fujian and northern Fujian.Therefore, the spatial distribution of the tungsten polymetallic deposits in South China is not traditionally thought of as a near-EW trend, but has a northerly or NE-EW distribution, - An important part of the metallogenic domain.