LATE JURASSIC (151–147 Ma) DIKE MAGMATISM OF THE NORTH-EASTERN MARGIN OF THE SIBERIAN CRATON
Dikes of intermediate and composition from the area of the Vyun deposit and Shumnyi occurrence assigned to the Yano–Kolyma gold belt (North-East Asia) were first dated at 151–147 Ma (Late Jurassic) based on U–Pb zircon ages (SHRIMP II method). Trace element distribution in the dike rocks is much like that un the previously studied basic dikes of Late Jurassic age observed in similar blocks – fragments of the Siberian craton margin. This fact permits their combination into a single complex. The dikes could have formed from mixed enriched and depleted mantle sources, probably in the north-east (in present-day coordinates) of the Siberian platform in the active continental margin setting. This event predated or was synchronous with the early (Late Jurassic) stage of the collision between the Siberian craton and the Kolyma-Omolon superterrane.