Petroleum Potential of the North Uralian Foredeep, Timan Pechora Basin, Russia

Abstract

Historically petroleum exploration in the North Uralian foredeep was focused on easy targets provided by high-relief structures in the western inverted and uplifted flank of the foredeep and the North Uralian foreland thrust belt. The structures were defined mainly by surface mapping, structural drilling and low-fold 2D seismic. First cycle of exploration has resulted in discoveries of about a dozen of oil and gas deposits including the giant Vuktyl gas-condensate field made mainly in 1960–1970ies. As the simple plays matured, oil and gas exploration shifted to fresh areas in the northern part of the basin, leaving large areas of the Upper Pechora foredeep virtually unexplored with only a handful of wells drilled there. A reinterpretation of vintage seismic and borehole data as well as new regional seismic lines provide important constraints for the regional geology and permit identification of new exploration opportunities. Revisited regional geology shows that the Upper Pechora foredeep may contain a significant yet-to-find potential. The buried Upper Devonian carbonate platform covering up to 3000 km² is seen as a potential focus of a new exploration campaign. It sits over a basement high in the north-central part of the fodeep and rimmed with an extensive system of reefs. These reefs and their drapes are viewed as prime exploration objectives, which are proven to contain prolific oil and gas deposits in better studied analogous areas of the basin. Additional plays include subtle traps as lowstand by-pass sands, dolomitized oolitic shoals, reef talus / debris aprons, lagoonal patch reefs and shoals. Significant opportunities are thought to exist in karstified Silurian-Lower Devonian carbonates truncated by the pre-Frasnian unconformity.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014