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大别山北部榴辉岩及英云闪长质片麻岩的锆石U Pb年龄分析表明 :北部榴辉岩相峰期变质时代为 2 2 6～ 2 30Ma左右 ;北部塔儿河一带英云闪长质片麻岩经历过印支期变质事件 ;大别山北部与南部超高压岩石中一致的 (2 2 6～ 2 30Ma)高压或超高压变质年龄表明 ,北部镁铁 -超镁铁质岩带中部分岩石也曾作为扬子俯冲陆壳的一部分 ,在印支期发生过高压或超高压变质作用 ;本区锆石发生过两期变质增生事件 ,一是印支期高压或超高压变质 ,另一期是燕山期热变质事件 ;榴辉岩及英云闪长质片麻岩的原岩形成时代为晚元古代 ;锆石U Pb年龄可用多期变质增生模型来解释。
Zircon U Pb ages of eclogite and diorite gneisses in the northern part of the Dabie Mountains show that the peak metamorphic age of eclogite facies in the north is about 226-26-30 Ma, The gneisses experienced Indosinian metamorphic events. The consistent (226-2630 Ma) high-pressure or ultrahigh-pressure metamorphic ages in the UHP rocks from the northern and southern parts of the Dabie Mountains indicate that the northern part of the mafic-ultramafic rocks As a part of the subducted continental crust, the rocks also occurred overpressure or ultrahigh pressure metamorphism in the Indosinian. Two stages of metamorphic and proliferative events occurred in the zircons of the area. One is the high pressure or ultrahigh pressure metamorphism during the Indosinian and the other one Is a Yanshanian metamorphic event; the eclogites of the eclogites and the Yingyun dioritic gneisses are formed in the Late Proterozoic; zircon U Pb ages can be explained by the multi-stage metamorphic model.