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根据大量天然变泥质岩石样品的相关数据, 采用经验标度方法, 修正了石榴石-白云母温度计. 采用非对称Fe-Mg-Mn-Ca石榴石活度模型和对称Fe-Mg白云母活度模型分别描述石榴石、 白云母的非理想混合性质. 所采用变质岩石的变质条件为490( 700℃、 238(1306 MPa. 其中, 以11个氧原子为基础计算的白云母中Fe原子数在0.03(0.19之间、 Mg原子数在0.04(0.16之间, 石榴石Fe/Mg比值在3.387(18.986之间、锰铝榴石分子在0.01(0.289之间、钙铝榴石分子在0.028(0.273之间. 假设压力计算误差为±200 MPa、 白云母中Fe、 Mg分析误差各为±5%, 石榴石中Fe, Mg, Mn, Ca的分析误差各为±5%, 则本文的石榴石-白云母温度计偶然误差为±37℃. 假设白云母中分别含有10, 20, 30, 40, 50%的Fe3+, 则计算得到的温度, 比将白云母中Fe全部作为Fe2+时得到的温度分别低1 ( 6, 2 ( 12, 3 ( 16, 5 ( 24, 7 ( 29℃. 根据修正的温度计计算温度不仅与石榴石-黑云母温度计计算结果十分接近, 并且能准确反映递增变质带、 热接触变质晕等典型变质地质体不同变质地带温度的有规律变化情况. 该温度计使用范围为绿片岩相至角闪岩相的低压至高压变质岩石. 使用该温度计时, 可以将石榴石、 白云母中Fe全部作为Fe2+.
Based on the related data of a large number of natural shale samples, the garnet-muscovite thermometer was modified by empirical scaling method. The asymmetric Fe-Mg-Mn-Ca garnet activity model and the symmetric Fe-Mg muscovite The degree model describes the non-ideal mixing properties of garnet and muscovite, respectively. The metamorphic rocks metamorphic conditions are 490 (700 ℃, 238 (1306 MPa), in which the number of Fe atoms in muscovite calculated on the basis of 11 oxygen atoms At 0.03 (0.19, the number of Mg atoms is between 0.04 (0.16, the garnet Fe / Mg ratio is between 3.387 (18.986), the mullite molecules are between 0.01 (0.289), the almandine molecules are between 0.028 0.273. Assuming that the error of pressure calculation is ± 200 MPa, the errors of Fe and Mg in muscovite are ± 5% and the errors of analysis of Fe, Mg, Mn and Ca in garnet are ± 5% The accidental error of the stone-muscovite thermometer is ± 37 ° C. Assuming that the mica contains 10, 20, 30, 40, 50% Fe3 +, respectively, the calculated temperature is higher than the temperature obtained when all the Fe in the muscovite is taken as Fe2 + Respectively, low 1 (6, 2 (12, 3 (16, 5 (24, 7 (29 ℃. According to the revised thermometer to calculate the temperature It is not only close to the result of garnet-biotite thermometer, but also can accurately reflect the regular change of temperature in different metamorphic zones such as increasing metamorphic zone, thermal contact metamorphic halo, etc. The thermometer is used in the range of greenschist facies to angle Low-pressure to high-pressure metamorphic rocks of amphibolite facies, and when using this thermometer, all of Fe in garnet and muscovite can be regarded as Fe2 +.