Organic matter maturation stages in Tutleim formation rocks depending on maceral composition

Abstract

The paper presents the results of coal petrographic and geochemical studies of the Tutleim Formation rocks organic matter in the area of the Em-Egovskaya summit. Five macerals were identified that compose the organic matter of the studied formation: “standard” bituminite, “atypical” bituminite, radiolarian organic matter, alginite and vitrinite, as well as bitumen and bitumen films, which are the products of the original organic matter transformation. The metamorphosis in macerals during catagenesis is described, and the order of their entry into the generation phase is established. It has been shown that alginite starts transforming first, then “standard” bituminite, “atypical” bituminite, and the last one is the radiolarian organic matter. The results obtained were confirmed by the laboratory modeling of the further organic matter transformation. New bitumens are formed with different fluorescent properties compared to the initial ones. The results obtained in combination with the study of changes in the composition of both macerals and bitumen can make it possible to assess the contribution of individual organic matter microcomponents to the process of petroleum hydrocarbons generation.