The Paleozoic Stage of the Bogdo Massif Alkaline Rocks Formation, Arctic Siberia: Data of ⁴⁰Ar/³⁹Ar Dating Results

The Ar-40/Ar-39 age is determined for K-bearing minerals from high-K nepheline syenite (rischorrites), liebenerite and carbonatized nepheline syenite, and pseudoleucite syenite of the Bogdo alkaline massif (Arctic Siberia). The polychronous formation of alkaline complexes of the Tomtor type at the Paleozoic stage is revealed from summarizing and analysis of the Ar-40/Ar-39 age data on the thermochronological diagram for minerals of rocks of the Tomtor massif, Udachnaya-Vostochnaya kimberlite pipe, and alkaline rocks of the Bogdo massif. The isotopic data indicate a complex three-stage evolution of rocks of the massif with the most productive Late Devonian-Early Carboniferous rare metal-rare earth element mineralization. The Devonian stage of the formation of the Tomtor and Bogdo massifs is related to the impact of the Vilyui plume on the eastern margin of the Siberian Craton. A similar age range is registered during the formation of rocks of the Kola alkaline province.