There were investigated the composition and morphology of Lower Cretaceous formations within the Gurarinsko-Sobolin oil field (Tomsk region). According to the facies, litho-petrographic and electro-facies analyses, the sedimentation occurs under the transition conditions from shallow sea to coastal-sea and continental environment. There were determined the favorable and unfavorable sedimentation and post-sedimentation factors and their influence on the formation of terrigenous reservoir rock properties.