Isotopic molecular and fraction level changes of organic matter in carbon-rich rocks during maturation and simulation

The results of molecular level studying of the carbon isotopic composition of bitumens from the rocks of different organic matter maturation and artificially matured rocks are presented. In the case of domanic (Middle Frasnian) organic matter the isotopic n -alkanes profiles of naturally and artificially matured rocks are similar indicating correctness of artificial maturation. In the case of Upper Jurassic shales we demonstrated that source of n -alkanes of bitumens is not uniform at different maturation stages.