中文摘要:对稀有金属花岗岩的成因主要有两种认识——岩浆熔体结晶和自交代作用。本文从如下四方面讨论岩石成因；1．稀有金属矿化地段位于岩体顶部，呈似层状、似脉状分布；2．矿化岩石具溶蚀、穿切、假象及变晶结构；3．矿物包裹体测温和稀有金属矿物形成温度低；4．斜长石为An<3的钠长石。文章认为大多数稀有金属花岗岩是由自交代作用形成，只有极少数——近地表产物，是由岩浆熔体结晶形成的。
Abstract:Based on an analysis of the following geological phenomena, the authors hold that most of the rare metal granites must have been formed by autometasomatism whereas only very few ones are products of magmatic crystallization: l. The rare metal granite is frequently rich in alkaline and volatile minerals and often displays a zoned distribution of various minerals (Figs. 1, 2) as well as an obvious variation in petrochemical and mineralogical compasitions in upward direction (Figs.3,4) ; 2. In this kind of granites there always exists a substitution of one mineral for another, thus giving birth to such alterations as albitization, greisenization and topazization (photos l-12); 3.The thermometric data of inclusions in two rock bodies suggest that the formation temperatures of quartz can be divided into two groups, i.e., >500℃ and <500℃, with the first group probably denoting temperatures of magmatic crystallization and the second group those of metasomatism (the formation temperatures of microlite and manganotantalite, i.e., 315-320℃, are consistent with those of the second group) . 4. Albite in these granites is invariably characterized by An<3 while K-feldspar by Ab
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袁忠信, 白鸽, 杨岳清.1987.有金属花岗岩型矿床成因讨论[J].矿床地质,6(1):88~96.1987.A Discussion On Petrogenesis Of Rare Metal Granites[J].Mineral Deposits6(1):88~96
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