Birth and evolution of a cryogenian basin: Glaciation, rifting and sedimentation in the Vorogovka basin, Siberia

The Vorogovka Basin records the establishment and infilling of a rift-related basin during Cryogenian time. Its infill records the whole spectrum of continental clastic and carbonate shelfal to deep marine systems. Initiation of the Vorogovka trough as a sedimentary basin was accompanied by subsidence, and the accumulation of diamictites and conglomerates, of probable glacial affinity. The accumulation of Sturtian-age diamictites and the unsorted gravelstones resting on a metamorphic basement was coeval with rifting. Based on a facies analysis, it is shown that the Vorogovka trough demonstrates the evolution of a basin characterized initially by a half-graben with glaciofluvial deposits, and with a shelf shallow-marine shelf passing into a slope at the passive continental margin side. Episodic re(activation) of trough bounding faults can be illustrated on the basis of palaeocurrent analysis of fluvial–deltaic plain deposits, in deepwater fans and in shelfal, tide-related sediments. The final stage in basin evolution was characterized by the establishment of carbonate systems of probable microbial affinity and mixed tidal siliciclastic–carbonate sediments in the outer shelf. The phases of subsidence and palaeogeographic evolution proposed herein provide the basis for correlation between Cryogenian sediments of the Vorogovka Basin with those on other continents.