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The internal structures of zircons in eclogite from Huangzhen have been studied by cathodoluminescence (CL) microscopy. Two growth stages were distinguished: protolith magmatic cores and metamorphic overgrowth rims. These different domains were analyzed for trace elements using LAM-ICP-MS. The protolith and the overgrowth zircons have different trace elements characteristics. The trace element contents of protolith zircons are high and very variable. The overgrowth zircons show a typical trace element feature of equilibrium with garnet, e.g. low contents of HREE (132.2-197.6μg/g) and small differential degree of HREE ((Yb/Gd)cN=8.6-11.9). The contents of Nb, Ta and the ratio of Nb/Ta are lower in the metamorphic domains (0.5-1.4μg/g, 0.7-1.5μg/g, 0.3-1.3, respectively) than in the protolith domains (3.8-19.7μg/g, 2.7-12.1μg/g, 1.0-4.6, respectively). This is the first time to give the evidence that the metamorphic zircon equilibrates with the rutile, which formed during the peak metamorphic stage. T
The internal structures of zircons in eclogite from Huangzhen have been studied by cathodoluminescence (CL) microscopy. Two growth stages were distinguished: protolith magmatic cores and metamorphic overgrowth rims. These different domains were analyzed for trace elements using LAM-ICP-MS. The protolith and the overgrowth zircons have different trace elements characteristics. The overgrowth zircons are high trace elements feature of equilibrium with garnet, eg low contents of HREE (132.2-197.6 μg / g) and small differential degree of HREE ((Yb / Gd) cN = 8.6-11.9). The contents of Nb, Ta and the ratio of Nb / Ta are lower in the metamorphic domains (0.5-1.4 μg / g, / g, 0.3-1.3, respectively) than in the protolith domains (3.8-19.7 μg / g, 2.7-12.1 μg / g, 1.0-4.6, respectively). This is the first time to give the evidence that the metamorphic zircon equilibrates with the rutile, which formed during the peak m etamorphic stage. T