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阿拉夏位于巴西米纳斯吉拉斯州西北部,帕腊奈巴河与格兰德河之间,1953年发现.1961年投产探明Nb_2O_5储量43亿磅,品位Nb_2O_53.3%,占资本主义世界已探明储量的一半(世界主要铌矿床已探明储量为85亿磅).产量为资本主义世界总年产量0.49亿磅的71%,1981年年产量预计可达0.55亿磅,1983年将扩大至1.1-1.4亿磅,届时当大大超过近年的世界总年产量. 矿床为一面积达10km~2的穹窿状碱性岩岩盘:围岩为层状灰岩、石英岩及顶部千枚岩.岩盘引起交代作用,硅酸盐岩石多长霓岩化,灰岩变成了含磁铁矿、钛铁矿、烧绿石、磷灰石、重晶石及黄铁矿等矿物的碳酸岩:渗透力差的千枚岩盖层阻止了
Arathi is located in the northwestern Minas Gerais state of Brazil between the Parnaiba River and the Rio Grande, discovered in 1953. 1961 put into operation proved Nb_2O_5 reserves of 4.3 billion pounds, grade Nb_2O_53.3%, accounting for capital Half of the world’s proven reserves (proven reserves of 8.5 billion pounds for the world’s major niobium deposits), 71% of the 49 million pounds of gross annual capitalist world production and 1981 annual production of 0.55 billion pounds The year will be expanded to 110-140 million pounds, which will greatly exceed the total annual output of the world in recent years. The deposit is a dome-shaped alkaline rock disk with an area of 10km ~ 2: the rock is layered limestone, quartzite and the top Phyllite. The metasomatism was caused by metasomatism, the silicification of rocks was long, and limestone turned into magnetite, ilmenite, pyrochlore, apatite, barite and pyrite Carbonate rocks of minerals: The poorly permeated phyllite cap is prevented