|Article # 33_2013||submitted on 07/09/2013 displayed on website on 09/10/2013|
|20 p.||Skachek K.G., Larichev A.I., Bostrikov O.I.|
|Geological and geochemical criteria of oil and gas bearing section in the contact zone of the Pre-Jurassic basement and sedimentary cover in the sublatitudinal Pre-Ob region|
|Numerous oil and gas fields, including the Rogozhnikovskoe large field and the Talinskoe giant field, have been discovered in Frolovsk and Priuralsk oil-and-gas bearing regions in Western Siberia. This area is covered with a dense network of wells reaching the Pre-Jurassic basement in the unconformity contact zone between the Pre-Jurassic basement and the sedimentary cover. The unconformity contact zone is poorly investigated by drilling within the territory of "Lukoil-Western Siberia" Ltd. activity in the sublatitudinal Pre-Ob Region. However, oil inflows enabling to rely upon the discovery of commercial pools have been obtained here as well. Assumed, reservoirs of hydrocarbons are as follows: crushing and fracture zones, weathering crusts of carbonate and effusive rocks belonging to the basement highs, sand-silt traps of the lower layers of the sedimentary cover. Geochemical data proved that oil source are predominantly clayey layers: Levinsk, Kiterbyutsk, Laydinsk, and Leontievsk Formations, overlapping the basement highs (or adjacent to them) in different areas in the region. Kitchen of the most intense hydrocarbon generation are confined to depressions of the 1st structural order. For the whole study area and especially for the most promising targets, distinguished by seismic, gravity, and geological-geochemical data were analyzed. The space genetic method as quantitative estimation of the initial hydrocarbon geological sources was used.
Key words: Western Siberia, sublatitudinal Pre-Ob Region, oil-and-gas content criteria, contact zone, oil and gas formation, quantitative assessment of resources.
|article citation||Skachek K.G., Larichev A.I., Bostrikov O.I. Geologo-geokhimicheskie kriterii neftegazonosnosti zony kontakta doyurskogo fundamenta i osadochnogo chekhla v Shirotnom Priob'e [Geological and geochemical criteria of oil and gas bearing section in the contact zone of the Pre-Jurassic basement and sedimentary cover in the sublatitudinal Pre-Ob region]. Neftegazovaya Geologiya. Teoriya I Praktika, 2013, vol. 8, no. 3, available at: http://www.ngtp.ru/rub/4/33_2013.pdf|