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Ellis和Green(1979)对石榴石—单斜辉石KD(Fe,Mg)地质温度计的实验校正与B类、C类榴辉岩主要相和次要相的简单体系实验资料相吻合,亦与相平衡结果的热力学简单外推相吻合。使用榴石石—单斜辉石KD标度计时,自然组合的显微探针分析必须对Fe~(3+)做校正。榴辉岩的地质测压术更为困难。斜长石的缺失定量地确定了石英檀辉岩的压力下限。平衡压力的其它资料来源于榴辉岩次要相的稳定性实验工作。诸如硬柱石、黝帘石,滑石,钠云母,钠长石和透闪石。根据热力学分析,许多研究详细的石榴石和单斜辉石的产区所需压力最低为12～13kb。根据高温下干的基性成分实验工作的远外推,早期6～9kb的估计是不正确。榴辉岩很可能形成于很高的水压下;水压远小总压的条件可以出现,但一般不是必须条件。地壳榴辉岩可以概略地划分为三类。低温类(450～500℃),有硬柱石的假象;高温类(600～750℃),含有滑石和蓝晶石或者产于同变质泥质岩含有这一组合的地体中;中温类(500～600℃),既无硬柱石亦无滑石—蓝晶石。这些岩石的推测压力变化在12～18kb之间,一些地区在形成粗粒石榴石和绿辉石的过程中,其压力可达20kb,或更高一些。如此高的压力必然是大陆边缘俯冲作用的结果。塔斯马尼亚和挪威南部的石榴石—绿辉石核部与边部的成分差,以及厄瓜多尔Raspas组的榴辉岩矿物成分范围均指示了温、压增加的递进变质的俯冲作用过程,但没有得到证实。许多榴辉岩的次生绿片岩组合标志着在相对高温条件下的上升活动。另一方面,等压冷却之后,上升至地表之前,可能在浅部发生另一期的、温度上升的变质作用。最低的T/P平衡条件见于较年轻(晚白垩—第三纪)的产区,包括了所有的与硬柱石有关的实例。它们视平均俯冲作用地热梯度约为埋深的11℃/km,或者更低些。最老的(晚元古—早元古代)榴辉岩见有最高的视地热梯度约为16℃/km。这包括与白云岩有关的样品。尽管样品相对较少,计算中误差较大,但这一视俯冲作用地热梯度范围亦可表明,适于形成低温地壳榴辉岩的条件在较晚的地质历史中更为普遍。
The experimental calibration of the garnet-clinopyroxene KD (Fe, Mg) geothermometer by Ellis and Green (1979) is consistent with the experimental data of the simple system of the major and minor phases of the B and C eclogites. The thermodynamic simple extrapolation of the phase equilibrium results is consistent. Using a garnet-clinopyroximate KD scale, naturally-combined microprobe analyzes must be calibrated for Fe 3+. Geological manometry of eclogites is more difficult. The absence of plagioclase quantitatively determined the lower limit of the pressure of quartz dacitestone. Other sources of equilibrium pressure are derived from the stability experiments of the secondary phases of eclogites. Such as dacite, zoisite, talc, mica, albite and tremolite. According to the thermodynamic analysis, the pressure required for the production of many of the most studied garnets and clinopyroxenes is 12-13 kb. According to far extrapolation of experimental work on dry base at high temperatures, the estimation of 6 to 9 kb early is not correct. Eclogites are likely to form under very high water pressure; conditions of far lower total pressure of water pressure may occur but are not generally required. Crust eclogites can be roughly divided into three categories. Low-temperature type (450-500 ℃) with the illusion of a dacite; high-temperature type (600-750 ℃) containing talc and kyanite or produced in the same metamorphic mudstone containing this combination of the ground; 500 ~ 600 ℃), neither the nor the dacite nor kyanite - kyanite. The speculative pressures for these rocks vary between 12 and 18 kb, and pressures can reach 20 kb or more in some areas during the formation of coarse-grained garnets and omphacites. Such a high pressure must be the result of continental margin subduction. The poor composition of the nuclei and edges of the garnet-omphacite in Tasmania and southern Norway, and the eclogite mineral composition of the Raspas Formation in Ecuador all indicate a progressive metamorphic subduction process with increasing temperature and pressure , But it has not been confirmed. The secondary greenschist combination of many eclogites marks ascending activity at relatively high temperatures. On the other hand, after the isobaric cooling, another phase of temperature-rising metamorphism may occur in the shallow part before it rises to the surface. The lowest T / P balance conditions are found in the younger (Late Cretaceous-Tertiary) producing area and include all examples related to lianas. They are subducted by average geothermal gradients of about 11 ° C / km, or lower. The oldest (Late Proterozoic-Early Proterozoic) eclogites had the highest apparent geothermal gradient of about 16 ° C / km. This includes samples related to dolomites. Despite the relatively small number of samples and large computational errors, this subduction-like geothermal gradient range also suggests that conditions suitable for the formation of low-temperature crust eclogites are more prevalent in later geological history.