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The overview of the Phanerozoic volcanism of the northeastern Eurasia (a territory that includes Russia and other CIS countries) is based on the analyses of the Atlas of paleovolcanological maps of 1:5,000,000 scale compiled by geologists from Russia and other CIS countries. The Atlas consists of five maps (age intervals V-S1, S2-C1, C2-T, J-K, Pg-N) showing the present and the reconstructed distributions of various volcanic and volcanogenic-sedimentary formations, the types of eruptions, the paleogeographical settings, and the economic minerals associated with volcanism.
Evolutionary tendencies of the Phanerozoic volcanism of the last 600 mln years manifest in the diminishing of its intensity, the increase of the portion of andesites and rhyolites, and the increase of the potassium content in volcanic rocks. Moreover, the predominant submarine settings change to subaerial, the portion of the sedimentary rocks within the volcanogenic-sedimentary sequences diminishes, and the periods of the volcanic activity became shorter. In the course of these processes the role of Ag, Mo, W, Sn, Pb among the economic minerals of volcanic origin increases, while the role of Fe, Cu, Zn decreases. These basic evolutionary tendencies were repeatedly complicated by rifting accompanied by outflow of basalts (including mid-alkaline varieties) and the formation of the ultramafic alkaline volcanic rocks and the kimberlites. The cratons, continental margins, as well as mobile regions were subjected to destruction which interrupted the trend of the volcanic evolution of the latter, and controlled the appearance of U, Hg, the fluorine, and the native Cu deposits. Various types of identified volcanic areas (provinces, belts, zones, and regions) differ in rock composition and the paleogeographic setting. The types of the accompanying economic minerals show closer correlation with types of these areas than with certain volcanic association. The epochs of the maximum eruptions of basalts (D2-3, T1 - on cratons and on continental margins, a, S1, D2-3, T1, J3 - in mobile regions) or rhyolites, dacites, and andesites (D2-3, C2-P, K-Pg - in mobile regions) as indicators of either extensional or compressional settings correspondingly are either alternating or coinciding. In general, the evolutionary changes resulted from the formation of the Eurasian supercontinent and the involving of the continental crust into the magma-producing processes.
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