A combined study of garnet and zircon from the same growth stages can provide effective constraints on the pressure–temperature-time path of metamorphic processes. This is illustrated by distinguishing different episodes of garnet and zircon in metabasites from North Qaidam. Two different garnet domains grown under eclogite- and granulite-facies conditions were recognized to have different trace elements and inclusions. The variable trace elements are ascribed to the coexisting MREE-rich minerals and whole-rock compositions under eclogite-facies conditions, and to variable growth of feldspar and consumption of precursor garnet at the continuous granulite facies metamorphism. The majority of zircon cores with ages of 430–441 Ma and zircon rims with ages of 419–424 Ma record metamorphism at eclogite-facies and granulite-facies, respectively. They exhibit different trace elements and Hf-O isotopes, indicating zircon growth via different mechanisms with differential involvement of precursor zircon and other minerals as well as anatectic melts under eclogite- and granulite-facies conditions. The metabasites experienced an increase of metamorphic thermal gradients with time and thus the tectonic transition from deeply continental subduction for Alpine-type HP to UHP eclogite-facies metamorphism at 2.6–3.1 GPa and 827–864 °C through decompressional exhumation to the lower crust for Barrovian-type HP granulite-facies overprinting at 1.05–1.70 GPa and 725–872 °C, eventually to extensional exhumation to the mid-crustal level for Buchan-type low-pressure amphibolite-facies overprinting at 0.34–0.56 GPa and 528–667 °C in the collisional orogen. While HREE disequilibrium between the two minerals is common, the equilibrium HREE partitioning may be achieved between zircon and garnet rims during crustal anatexis at the late HP granulite-facies metamorphism.

对同一生长阶段的石榴石和锆石进行联合研究，可以有效地限制变质过程的压力-温度-时间路径。这可以通过区分柴北缘变玄武岩中不同的石榴石和锆石片段来说明。在榴辉岩和麻粒岩相条件下生长的两种不同的石榴石域被认为具有不同的微量元素和包裹体。可变微量元素归因于榴辉岩相条件下富含MREE的矿物和全岩成分共存，以及在连续麻粒岩相变质作用下长石的可变生长和前体石榴石的消耗。大多数年龄为 430-441 Ma 的锆石核和年龄为 419-424 Ma 的锆石环分别记录了榴辉岩相和麻粒岩相变质作用。它们表现出不同的微量元素和 Hf-O 同位素，表明锆石通过不同的机制生长，前体锆石和其他矿物的不同参与以及榴辉岩和麻粒岩相条件下的深熔熔体。变质岩经历了随时间增加的变质热梯度，因此构造从高山型 HP 的深大陆俯冲到 2.6-3.1 GPa 和 827-864 °C 的超高压榴辉岩相变质作用，通过减压折返到下地壳Barrovian 型 HP 麻粒岩相在 1.05-1.70 GPa 和 725-872 °C 下叠印，最终以 0.34-0.56 GPa 和 528-667 GPa 叠印到 Buchan 型低压角闪岩相叠印到中地壳水平碰撞造山带中的°C。