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葡萄牙产有三个铀矿床(Urgeirica、Bica和Cunha Baixa)的花岗岩的其特点是铀含量高,含量变化大,地表含量为4-17ppm,钍含量为20-37ppm。含铀、钍的副矿物主要有:晶质铀矿(含有少量ThO_2)、磷钇矿、独居石、锆石,磷灰石也含少量铀和钍。在脉型铀矿脉壁上,强烈的绢云母化蚀变是由含盐度较低的(相当于氯化钠重量的1.1-5.8％)含水溶液造成的,它的温度可达200-250℃。对白色云母的详细分析能区分出几个世代:岩浆期的、岩浆期后的和矿脉边缘多硅白云母。铀矿脉的周围环境明显看出溶液演化复杂,这说明原生铀矿化的热液成因。
Granite with three uranium deposits (Urgeirica, Bica and Cunha Baixa) in Portugal is characterized by high levels of uranium, large variations in content, surface contents of 4-17 ppm and thorium contents of 20-37 ppm. The main minerals containing uranium and thorium include: crystalline uranium (with a small amount of ThO 2), xenotime, monazite, zircon and apatite also contain small amounts of uranium and thorium. In vein-type uranium vein walls, intense sericitization alteration is caused by aqueous solutions of lower salinity (equivalent to 1.1-5.8% by weight of sodium chloride), with temperatures up to 200-250 ° C . A detailed analysis of the white mica can be distinguished for several generations: magmatic, post-magmatic and veins of phyllosite. The surrounding environment of uranium veins clearly shows that the evolution of the solution is complex, indicating the hydrothermal genesis of primary uranium mineralization.