Abstract <p>The first Rb–Sr and ¹⁴⁷Sm–¹⁴³Nd results on Early Mesoproterozoic rift-related picrite–picrobasalt volcanism and metamorphism have been obtained in the northern part of the Rybinsk-Panimba volcanic belt. Petrogeochemical data indicate the sedimentary–terrigenous nature of most of the samples from the Mikhailovskii site taken from the section of the Kordinskii formation. The presence of a noticeable admixture of basitic matter in them in the form of tuffs or outwashed volcanomictic material is confirmed by the increased content of MgO and CaO and reduced REE, Zr, Hf, and Nb. The results of geothermobarometry and the analysis of the metamorphism features of volcanogenic–sedimentary rocks of the reference sites indicates the inhomogeneous character of the PT conditions of the source rock transformation: 4.8–4.9&#xa0;kbar/527–549°C for picrobasalt metatuffites; 5.0–5.8 kbar/543–612°C for metabasites; 3.5–4.6&#xa0;kbar/522–636°C for metapelites. The established age of rift-related picrite–picrobasalt volcanism and associated processes of metamorphism in the Precambrian of the central Yenisei Ridge correlates with the timing of formation of plagiogranites of the Nemtikhinskii terrane and with the reference Mashak plume magmatism in the Southern Urals, which manifested themselves in the geodynamic setting of extension during the breakup of the Nuna supercontinent.</p>