Аннотации:
Polycyclic hydrocarbons (biomarkers) were detected in the organic matter of Paleozoic and pre-Paleozoic rocks from the Romashkinskoe oil field in the Volga-Ural region using gas chromatography-mass spectrometry. Coefficients were calculated from the ratio between tetra- and pentacyclic hydrocarbons, and the facial genetic types, possible generation sources, and evolution transformation conditions of the initial organic matter were determined from the array of these coefficients. © Pleiades Publishing, Ltd., 2010.