Plume magmatism in the northeastern part of the Altai–Sayan region: Stages, source compositions, and geodynamics (exemplified by the Minusinsk Depression)

Abstract

The results of geochronological (U–Pb, Ar–Ar), geochemical, and isotopic (Sr, Nd) studies of the Ordovician and Devonian mafic volcanic–subvolcanic rock associations of the Minusinsk Depression are presented. The obtained ages of magmatic associations and the basite composition, considering previous studies, witness to the impact of two mantle plumes different in age (Late Cambrian–Ordovician and Devonian) on suprasubduction rock complexes in active continental margin settings.