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尼日利亚名列世界主要锡和铌铁矿产地之中,其主要来源是近代的冲积矿床和砂积矿床。据信,这些矿床都是来自尼日利亚北部年轻花岗岩省的侵入体。众所周知,在整个花岗岩体中均分散有一些主要的锡石和铌铁矿,而且目前正从分解了的母岩和云英岩化(带)脉以及石英条带中开采锡石和铌铁矿。然而,在年轻的花岗岩省中部明显缺乏脉状锡矿床。 当这类易于开采的冲积矿床日趋枯竭时,人们正把相当大的注意力集中于勘探大型的浸染矿床。这类
Nigeria ranks among the world’s major tin and niobium iron ore producing areas, with the main sources of modern alluvial deposits and sand deposits. It is believed that these deposits are intrusions from the young granite provinces of northern Nigeria. It is well-known that some of the major cassiterite and niobite are dispersed throughout the granite body and that cassiterite and niobite are currently being mined from decomposed mother rocks and dolostones and quartz bands. However, there is a clear lack of vein-like tin deposits in the middle of the young granite province. When such easy-to-exploit alluvial deposits are depleted, considerable attention is being focused on the exploration of large diagenetic deposits. This class