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最近,在柴北缘中段的锡铁山地区新发现有榴辉岩的出露,与这之前在柴北缘西段的鱼卡地区和东段都兰地区发现的榴辉岩一起构成了一个长350km的榴辉岩带。通过对鱼卡地区和锡铁山地区榴辉岩的对比研究显示,它们在围岩特征、岩石的显微结构、矿物组合,特别是它们的峰期温压条件、其减压过程的PT轨迹以及岩石的同位素特征等具有明显的差异。鱼卡榴辉岩的峰期变质温度较低,保存有进变质的矿物组合和石榴子石生长环带,显示出与快速折返有关的
Recently, the eclogites have been newly discovered in the Xishishan area in the middle of the northern Qaidam and together with the eclogites previously found in the Yuka area in the western segment of the northern Qaidam and the Dulan area in the eastern segment constitute a 350-km Eclogite belt. By comparing the eclogites in the Yuka and Xitiaishan areas, it shows that their characteristics of the surrounding rock, the microstructure of the rock, the mineral assemblage, especially their peak temperature and pressure conditions, the PT trajectory of the decompression process As well as the isotopic characteristics of rocks have obvious differences. The peak metamorphic temperature of the eclogites was lower with the presence of metamorphic mineral assemblages and garnet growth annuli, which were shown to be associated with rapid reentry