This paper reports on the issues on the study of the lithological and petrographic composition and formation of oil occurrences within the fields of the Surgut Dome and the Frolov Megabasin. It has been revealed that the formation of the oil occurrences of the sedimentary cover is associated with the peculiarities of the geological structure and the oil-bearing capacity of the basement rocks. In the study area, a high level of oil-bearing sedimentary cover is observed within the central part of the Surgut Dome. The Pre-Jurassic part of the section can have additional sources of intensification of hydrocarbons in the Lower–Middle Jurassic deposits. The presence of deep fault zones is the search criterion for the detection of secondary reservoirs in them, both in the destruction zones, basement, and in the Lower–Middle Jurassic deposits. Therefore, fields can be formed due to deep fluids vertically ascending through faults that cross the basement and the sedimentary cover. This paper also reports on the potential oil and gas bearing capacity of the Lower–Middle Jurassic deposits. In this regard, study of granitoid massifs, the degree of detail in distinguishing sedimentation conditions, and establishment of contact zones between the sedimentary cover and underlying formations have to be considered.