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苏鲁超高压变质带的形成时代究竟是印支期还是新元古代争议始终很大。对山东胶南地区超高压变质带中超镁铁岩和榴辉岩的锆石激光拉曼、阴极发光和离子探针原位定年的研究获得超高压变质作用发生的时代为印支期。其中超镁铁岩含柯石英锆石的年龄为221±12Ma,该深成岩侵位时代为新元古代(581±44Ma)。此外,锆石中另有约400Ma年龄记录,可能代表岩石形成后另有一期热事件。榴辉岩的下交点年龄为228±29 Ma,与超镁铁岩含柯石英锆石年龄一致,代表超高压变质时代;上交点为中元古代(1821±19Ma),代表原岩年龄,后者与其片麻岩围岩时代相一致,说明榴辉岩是原位俯冲。
Sulu UHP metamorphic belt formation era what is Indosinian or Neoplasmic controversy has always been great. The era of ultrahigh-pressure metamorphism of the zircon laser Raman, cathodoluminescence and ion probe dating of ultramafic and eclogite in the UHP metamorphic belt in the Jiaonan area, Shandong Province, was Indosinian. The age of the kerogenite with ultramafic rocks is 221 ± 12Ma, and the emplacement time of the deep plutons is Neoproterozoic (581 ± 44Ma). In addition, another 400 Ma ages record in zircon may represent another thermal event after the rock was formed. The eclogitic dating point of eclogites is 228 ± 29 Ma, which is consistent with the age of coesite zircons from the ultramafic rocks, representing the epochs of the UHP metamorphism. The turning point of the eclogites is the Mesoproterozoic (1821 ± 19Ma) They are consistent with their gneiss rock age, indicating that the eclogite is in situ subduction.