Выпуск: 8 , Том: 52 , Год издания: 2011

On the basis of available sedimentological, isotope-geochemical, and geophysical data, we have refined the intrabasinal correlation and the structure of Mesoproterozoic deposits of the Baikit anteclise. A pre-Vendian section was stripped within the Baikit anteclise, which can be correlated with the section of the Mesoproterozoic Teya and Sukhoi Pit (pre-Pogoryui) Groups of the Yenisei Ridge. Most of the overlying deposits of the Tungusik Group were destroyed during the tectonic events in the Early Neoproterozoic (-860 Ma) and in pre-Vendian time. Using the results obtained, we have refined the variations in the sedimentation environments of Mesoproterozoic deposits in the Baikit anteclise and Yenisei Ridge and constructed paleogeographic schemes for particular time intervals in the modern frame of references. The predominance of peritidal complexes and numerous signs of subaerial exposition indicate that the carbonate accumulation was periodically interrupted. In the periods (sometimes, long) when this process stopped, fine silicoclastic material transited from the shelf edge into a deep basin localized southwest of the Baikit anteclise. The longest transition periods were in Early Yurubchen, Dolgokta, and Late Vingol'da time, though the main flow supplying silicoclastic material to the Yenisei Ridge passed south of the Baikit carbonate shelf. In the Mesoproterozoic, the basin with predominantly carbonate sedimentation occupied a vast area in the western Siberian Platform, extending to the western margin of the Anabar Shield, where the Mesoproterozoic deposits were similar in structure and isotope-geochronological and isotope-geochemical characteristics to the pre-Vendian deposits of the Baikit anteclise. Most part of the area with carbonate sedimentation in the Baikit anteclise was remote from the shelf edge. The Mesoproterozoic shelf was much wider than its fragments in the recent structure on the western margin of the Siberian craton.