Comment on Volodichev et al. Archean Zircons with Omphacite Inclusions from Eclogites of the Belomorian Province, Fennoscandian Shield: The First Finding. Minerals 2021, 11, 1029

Sergey G Skublov,Aleksey V Berezin,Laysan I Salimgaraeva

doi:10.3390/min12020141

Abstract

Volodichev et al. (Volodichev et al., 2021) reported on the first finding of omphacite (23%–25% Jd) inclusions in 2.68 Ga metamorphic zircons from Gridino eclogites and presented it as evidence for Archean eclogite-facies metamorphism in the Belomorian Mobile Belt. We believe that the Archean age of the garnets referred to by the above authors was estimated incorrectly. Our interpretation is that omphacite origin is related to Archean high-pressure granulite-facies metamorphism.

Highlights

One of the major problems in the study of Belomorian mobile belt (BMB) eclogites is determining the timing of their formation
Available geochronological data on BMB eclogites are interpreted in various ways
The dominant point of view of the Paleoproterozoic age of BMB eclogites is based on the results of a set of independent isotopic-geochemical dating methods, such as the local U–Pb method for heterogeneous zircons with magmatic cores and eclogite rims, as well as the Lu–Hf and Sm–Nd methods for rock-forming minerals of eclogite paragenesis

Summary

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Findings

Gridino using theGa