MORPHOLOGY AND DISTRIBUTION OF THE RIPHEAN DEPOSITS IN THE NORTHEAST OF THE ANABAR ANTECLISE

V. S. Staroseltsev, B. B. Shishkin, G. A. Berilko, T. V. Salnikova, P. N. Sobolev

The paper shows that the Riphean deposits, which are exceedingly important for tectonic evolution of the Siberian Platform cover and its petroleum potential, despite beliefs of many experts, are not continuous in the northeast of the Anabar anteclise and are detached in form of two isolated basins. Their cross-sections structures are principally different. The distinctions between them are in dislocations of the Riphean complexes, which is shown in four seismic sections (composite traverses), and in their formation compositions as well, which are successively considered in four age intervals of separated northeastern Olenyok and southwestern Udzhi-Sukhan basins in the article. The first Uchur interval of the Olenyok basin includes the Lower Riphean deposits, the second Aimchan interval – the Middle Riphean, the third and fourth Kerpyl and Lakhanda intervals – the Upper Riphean. Each cycle in the lower part is characterized by dominating terrigenous varieties, and the upper part is prevailed by carbonaceous ones. In four age intervals of the Riphean deposits of the Udzhi-Sukhan basin there are volcanogenic formations along with purely terrigenous and carbonaceous deposits. The authors give geochemical description of studied cross-sections and highlight the most promising petroleum levels mainly in the Olenyok basin.

Key words: Riphean basins, Riphean age intervals, Olenyok and Udzhi-Sukhan basins, geochemical properties, petroleum potential.

Download PDF