中文摘要:本文着重对天皮山伟晶岩的氧、氢、碳同位素的组成和成因进行了研究。经测定，伟晶岩中石英的氧同位素值域为12~14. 4‰；平均值为l3.8‰白云母的氧同位素值域为11.5 ~12.2‰，平均值为11.9‰。这些数值与其围岩的氧同位素值一致，表明伟晶岩导源于周围的变质岩。白云母的氢同位素值域为-30.3~ -59.4‰，平均值为-48.9‰，石英中流体包裹体中水的氢同位素值域为- 32~ -73.4‰，平均值为- 59.1‰。δ18OH2O和δDH2O 值域表明本区伟晶岩中的水主要来自岩浆水，少部分来自地表水。石英包裹体中的碳同位素值有- 5.5‰和-19.6‰两组，重碳可能来自地壳深部的原生碳，轻碳可能来自围岩中的有机碳。
Abstract:The Tianpishan ore district located in central Inner Mongolia is one of the well-known muscovite mines in China. The hydrogen, oxygen and carbon isotope compositions of fluid inclusions and minerals from the pegmatite are studied in this paper to approach its genesis. δ18O values of quartz minerals from the pegmatite range from 12‰ to 14.4‰, with the average being 13.8‰, whileδ18O values of muscovite minerals are within the limits of 11.5‰ to 12.2‰, averaging 11.9‰. These values are somewhat higher than the oxygen isotope values of pegmatites reported in foreign literature, but are consistent with those of the wall rocks in this ore district, suggesting that the material of the pegmatite might have come from the metamorphic rocks of this area. δD values of muscovite are in the range of -30.3‰ ~ -59.4‰, averaging -48.9‰, and δD values of waters in fluid inclusions of quartz extend from-32‰ ~ -73.4‰, averagely -59.1‰, quite in conformity with the values reported abroad. Theδ18OH2O -δDH2O range implies that the waters in pegmatite of this area were predominantly from magmatic water and partly from the surface water. Two groups of δ13C values are recognized for CO2 in fluid inclusions of quartz, i.e., -5.5‰ and -19.6‰. This indicates that the heavy carbon might have derived from the primary carbon in the depth of the crust and the light carbon from the organic carbon in the wall rocks.
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王时麒，郑淑慧，郑斯成，陈成业.1987.内蒙天皮山伟晶岩的碳、氢、氧稳定同位素组成及成因分析[J].矿床地质,6(3):85~90.1987.Hydrogen, Oxygen And Carbon Isotope Studies On The Genesis Of The Tianpishan Pegmatite In Inner Mongolia[J].Mineral Deposits6(3):85~90
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