15. Specifics of the eclogite-facies metamorphism in the Precambrian
Michael V. Mints, 2015. "15. Specifics of the eclogite-facies metamorphism in the Precambrian", East European Craton: Early Precambrian History and 3D Models of Deep Crustal Structure, Michael V. Mints, Ksenia A. Dokukina, Alexander N. Konilov, Irina B. Philippova, Valery L. Zlobin, Pavel S. Babayants, Elena A. Belousova, Yury I. Blokh, Maria M. Bogina, William A. Bush, Peter A. Dokukin, Tatiana V. Kaulina, Lev M. Natapov, Valentina B. Piip, Vladimir M. Stupak, Arsen K. Suleimanov, Alexey A. Trusov, Konstantin V. Van, Nadezhda G. Zamozhniaya
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In Chapter 2, we showed that the eclogite-facies metamorphism within the Mesoarchean–Neoarchean Belomorian eclogite province can be correlated with “hot” subduction. However, was such a thermal regime specific to the Archean? Comparison of pressure-temperature-time paths and data for peak metamorphic parameters demonstrates the general similarity of the Archean and Paleoproterozoic eclogites worldwide and their association with anomalously “hot” environments. In contrast, Phanerozoic high- and ultrahigh-pressure eclogite complexes formed in connection with “warm” subduction zones. The high-temperature character of the eclogite-facies metamorphism in the Proterozoic is impossible to explain through a distinctively anomalous thermal regime, as is often suggested for the Archean mantle. The occurrence of high-temperature conditions during eclogite-facies metamorphism can be attributed to either subduction of a mid-ocean ridge (Archean, Belomorian eclogite province) or to interaction with mantle plumes (Proterozoic).