... stratigraphy deposition environments facies Jurassic West Siberia Fig. 1. Generalized map of Callovian and Upper Jurassic facies regions in West Siberia and location of SDB-6. 1 — Yamal-Nadym subfacies (Abalak Formation), 2 — Upper Pur subfacies (Vasyugan Formation) of Pur-Irtysh facies; 3...

...Fig. 3. Lithology and geophysical characteristics of the Vasyugan Formation: A, Ob-Tara sub-region in the Krapivinskaya 201 well, B, Ob-Agan sub-region in the West Sorominskaya 16 well (for well locations see Fig. 2 ). Legend to Figs. 3 , 4 : Gr, Georgievka Formation, TM, Tyumen Formation...

... or younger source rocks in the study area. Core samples from the Lower Cretaceous Frolov Formation either are thermally immature (Hauterivian) or show little oil-generative potential (Berriasian-Valanginian). The Upper Jurassic Vasyugan Formation shows lower oil-generative potential than the Bazhenov...

...V.A. Kontorovich; S.A. Berdnikova; L.M. Kalinina; A.A. Polyakov A new approach to detection and mapping of oil and gas traps in the Callovian-Tithonian section on the basis of combined seismic, log, and core data has been tested in a field within the Vasyugan Formation. The sand bed U 1 1...

.... In the first of them, the Callovian-Oxfordian deposits include the Vasyugan and Abalak Formations; in the second, the Tochino and Sigov Formations; and in the third, the Naunak Formation. Lithological and mineralogo-petrographical studies invoking well logging, geochemistry, and paleontology showed...

... grains of terrestrial plants) and bio- and lithostratigraphic features of the uppermost Middle and Upper Jurassic part of the reference section from the Tyumenskaya superdeep borehole. The Vasyugan, Georgiev, and Bazhenov Formations are described in detail, taking into consideration...

... producing beds, is still much disputed. The article reports correlations between these beds at the level of zonal cyclites. More reliable age analogs of the Bazhenov Formation have been recognized in eastern-type sections. The diachronous nature of the upper boundary of the Vasyugan Formation...

... in the Middle Jurassic deposits suggest that the areas appropriate for hydrocarbon migration from petroleum-generating rocks of the Bazhenov and Togur Formations into Bajocian-Bathonian traps are the most favorable for petroleum deposition. Such are the areas where the marine sediments of the Vasyugan Formation...

...S. V. Meledina Collections of Middle-Upper Jurassic ammonites found in core samples from West-Siberian boreholes are described. New Upper Callovian species of Longaeviceras and one Lower Oxfordian species of Cardioceras have been discovered in the Abalak and Vasyugan Formations. The small-shell...