The effect of catagenetic maturity on the formation of reservoirs with organic porosity in the Bazhenov formation and peculiarities of their extension

Abstract

Results of Bazhenov formation deposits organic matter complex investigations to assess its oil generation potential and maturity are presented. Researches were performed by Rock-Eval pyrolysis, rock structure analysis using scanning electron microscopy and organic matter transformation and distribution in the bulk of rocks using luminescent microscopy. As a result of the research, the general pattern for the Bazhenov formation kerogen thermal maturity variability along Western Siberia was confirmed, and the high maturity areas delimitation around the Salym high and the Krasnoleninsky arch was significantly specified. The areas of anomalously high maturity are not related to regional patterns of sedimentation. The possible influence of thermal maturity on the unconventional reservoirs with kerogen porosity formation in the Bazhenov formation and the features of their distribution were established. High thermal maturity that refers to the end of oil window is one of the main condition for the Bazhenov formation oil capacity formation, but knowledge of maturity change through the area pattern is not a sufficient condition for unconventional reservoirs including that with kerogen porosity retrieval.