The Carboniferous low stand complex: a new conceptual petroleum play in the Kosyu-Rogov Foredeep, the Timan-Pechora Basin
Key words: Kosyu-Rogov Foredeep; Timan-Pechora Basin; oil; petroleum exploration; low-stand complex; pinchout zone;karst.
For citation: Sobornov K.O. The Carboniferous low stand complex: a new conceptual petroleum play in the Kosyu-Rogov Foredeep, the Timan-Pechora Basin. Geologiya nefti i gaza. 2022;(5):17–30. DOI: 10.31087/0016-7894-2022-5-17-30. In Russ.
Acknowledgement: The author would like to thank T.I. Grigorenko, V.N. Danilov, V.A. Zemchugova, V.F. Kolesnik, I.P. Korotkov, N.I. Nokonov for fruitful discussions of the geological setting and petroleum habitat of the study area.
Petroleum exploration in the Kosyu-Rogov Foredeep of the North Urals has been mainly based on testing of the four-way dip closures in the regionally prolific Upper Devonian deposits. This exploration method, which has been proved successful throughout much of the Timan-Pechora Basin, failed in the Kosyu-Rogov Foredeep. A study of petroleum systems in this area suggested that many anticlinal traps have been developed after the principal phase of the hydrocarbon migration. This left them undercharged. Another disadvantage is the limited development of reservoirs over much of the basin. On one side, it was mainly because the Kosyu-Rogov Foredeep continuously represented starved trough filled predominantly with shale deposits. On the other side, it was due to significant burial depths of the prospective intervals in the eastern Cis-Uralian part of the foredeep. A new conceptual exploration play related to Visean-Middle Carboniferous low-stand deposits is proposed based on an integrated reinterpretation of available geological and geophysical data. The low stand complex and its drape beds include prospective traps of structural and stratigraphic types. Testing of these traps may provide substantial petroleum reserves build-up. The low stand zone is identified in the western part of the Kosyu-Rogov Foredeep. It follows the eastern margin of the Upper Devonian-Tournaisian shelf extending in to the inner part of the trough.