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对北大别变质杂岩中的麻粒岩包体进行详细的氧同位素地球化学研究,发现其全岩δ~(18)O值偏低,为3.3‰～4.4‰。在麻粒岩相变质条件下,大别山麻粒岩包体的共存矿物对之间达到并保存了氧同位素平衡,后期退变质作用未明显破坏这种平衡。由矿物氧同位素地质测温得到的顶峰变质温度800～875C,与一般麻粒岩相变质温度相吻合。在变质作用之前或顶峰变质作用过程中,大别山麻粒岩包体的原岩曾与一δ~(18)O值低于3‰的外来流体发生了高温水—岩交换作用,并且这种交换作用在一定范围内是相对均一的。
The detailed study of oxygen isotope geochemistry of granulite inclusions in the North Dabie metamorphic complex shows that the δ 18 O value of the whole rock is as low as 3.3 ‰ ~ 4.4 ‰. Under the condition of granulite facies metamorphism, the isotope balance of oxygen isotopes is reached and preserved between the coexistent minerals in the Dabie Mountain granulite inclusions, and the late retrograde metamorphism did not obviously destroy the balance. The peak metamorphic temperature from mineral oxygen isotope geothermics is 800-875 C, which is consistent with the temperature of general granulite facies metamorphism. Prior to the metamorphism or during the summit metamorphism, the original rocks of the granulite inclusions in the Dabie Mountains had been subjected to high-temperature water-rock exchange with foreign fluids with δ 18 O values less than 3 ‰, and this exchange The role of a certain range is relatively uniform.