Paleogeography of the Bazhenov Formation of Western Siberia According to the Distribution of Rare Earth Elements

Abstract

The Bazhenov Formation is represented by Late Jurassic black shales. Russia is the first in the world by the reserves of shale oil, which is mostly related to the Bazhenov Formation. To reconstruct the sedimentation settings for the main types of formation of rocks, the distributions of lanthanides have been used. The results pointed to the formation of the Bazhenov deposits in relatively shallow environments, within the inner and outer shelf of the epicontinental sea, similarly to the Kara Sea or the East Siberian Sea. The deep-water part of the epicontinental sea was located north of the Latitudinal Priobye. These results confirm some previous estimates, but have been obtained on the basis of quite different and independent data. The geochemical study of different types of rocks of the Bazhenov Formation gave identical results, which testifies in favor of the reliability of the results obtained.