40Ar/39Ar dating of Usol'skii sill in the south-eastern Siberian Traps Large Igneous Province: evidence for long-lived magmatism

Main part of the Siberian Traps Large Igneous Province was formed in a short time‐span at the Permo‐Triassic boundary c. 250 Ma. New 40Ar/39Ar dating results for the Usol'skii dolerite sill in south‐eastern part of the province indicate its probable emplacement c. 6 Myr after the main Permo‐Triassic magmatic phase. Compilation of the published 40Ar/39Ar and U‐Pb ages implies that basaltic and related magmatism lasted in total as long as 22–26 Myr. Therefore, similar to other large igneous provinces, magmatism of the Siberian Traps combined voluminous short‐lived and less prominent long‐lived events.