Neoproterozoic intraplate magmatism along the western margin of the Siberian Craton: Implications for breakup of the Rodinia supercontinent

The fold-and-thrust belt of Yenisey Ridge is a key to understand the Precambrian tectonic evolution of the Siberian Craton as well as crustal evolution in the Central Asian Orogenic Belt. Here we report the occurrence of felsic and mafic dyke swarms in the Yenisey Ridge providing evidence for rift-related magmatism. The dikes and sills occur in narrow linear zones along faults, and show bimodal composition with geochemical features indicating intraplate settings. Zircon SHRIMP U-Pb analyses constrain the timing of emplacement of the dykes as 797-792 Ma. The magmatic event at c.800 Ma along the western margin of the Siberian Craton and other continental blocks can be correlated with the onset of the breakup of the Neoproterozoic Rodinia supercontinent. Post-Grenville episodes of regional crustal evolution are correlated with the synchronous successions and similar style within the Valhalla orogen along the Arctic margin of Rodinia and supports the spatial proximity of Siberia and North Atlantic cratons (Laurentia, Baltica, Svalbard) at c.800 Ma, as proposed for the Neoproterozoic paleogeographic reconstructions for the Rodinia supercontinent and as robustly constrained from large igneous province (LIP) record.