| 钪的地球化学与铁矿石成因 |
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| 引用本文：.1982.Geochemistry of Scandium as applied to the problem of iron ore genesis[J].Mineral Deposits,1(2):53~57 |
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| Geochemistry of Scandium as applied to the problem of iron ore genesis |
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| Abstract:The Sc contents of various iron ores and minerals in China have been determined by means of such techniques as neutron activation, atomic absorption spectrography and catalytical polarography. From the resulting analytical data certain regularity has been noted. Here are the facts along with my explanations: (1) Vanadium-bearing titanomagnetite ores of basic-ultrabasic association and spilite-type magnetite ores have higher average Sc contents (27ppm and 31ppm respectively). This is referable to the relatively high concentration of Sc in the basic-ultrabasic magma as well as to the readiness with which Sc3+ displaces isomorphously Mg2+ and Fe2+ in Fe-Mg silicates and Fe-Ti oxides. during the magmatic processes. (2) Sedimentary and metamorphosed sedimentary hematite ores or specularite ores have moderate Sc contents (10-14ppm).This is probably caused by the adsorption of Sc by colloidal Fe(OH)s precipitates. (3) The magnetite or hematite ores from iron deposits of hypabyssal 57 ore-magmatic type, pegmatitic type, skarn type, and (sedimentary~) volcano-hydrothermal type have lower Sc contents (3-9ppm). This may result from the lower content of Sc in dioritic magmatic-metallogenetic system and the limited displacement of Mg2+ and Fe2+ by Sc3+. Of various iron minerals, ilmenite from the vanadium-bearing titanomagnetite deposit has the highest Sc contents (average 29.5ppm)~ tita.nomagnetite from the vanadium-bearing titanomagnetite deposit has moderate Sc contents (average 9.2)~ magnetite (or martite), hematite and specularite from various iron ores have lower Sc contents (≤3.18pp.m). The higher Sc content of ilmenite is ascribable to the higher temperature of its formation, the larger amounts of Fe2+ it contains and the easier emplacement of Sc3+ in the lattice of this mineral, whereas the lower Sc content of hydrothermal magnetite is attributable to the lower Sc concentration of hydrothermal system and the difficulty with which Sc3+ displaces Fe2+. In short, the foregoing discussion has led the author to believe that the contents of Sc in ores and minerals can serve as a probable indicator in the ore genesis problem. |
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