The Northeastern Boundary of the Siberian Craton and Its Formation Peculiarities (Derived from Occurrences of Early Cambrian and Devonian Intraplate Magmatism)

摘要

The formation of the Siberian Craton ended in the Paleoproterozoic. Subsequently, it was repeatedly subjected to destruction in response to interaction between the lithosphere and the mantle plumes. The most significant events of that time were the Neoprot-erozoic and Middle Paleozoic rifting epochs, which determined the configuration of the Siberian Craton close to the present one. For example, the Neoprot-erozoic rifting epoch is correlated with the breakup of Rodinia [ 1 ]. This epoch culminated with separation of the craton from the Laurentian part of Rodinia in the late Neoproterozoic [2] and formation of its southern (in modern coordinates) boundary. The Middle Paleozoic rifting epoch resulted in the formation of the eastern boundary of the Siberian Craton [3]. The continental breakup was accompanied by the formation of a triple rift system, the best known branch of which is represented by the intracontinental Vilyui rift pinching out in the craton body [4]. Two other branches of this system determined the breakup boundary of the continent and separation of its eastern segments. These branches are represented by the Verkhoyansk and Sette Daban rifts, fragments of which are now observable in the Olenek (Kharaulakh segment) and South Verkhoyansk marginal zones of the Mesozoic Verkhoyansk fold-thrust belt (VFTB) [5].