Oil families and their potential sources in the northeastern Timan Pechorabasin, Russia

Oil and rock samples collected throughout the northeastern Timan Pechora ba sin identify key oil families and correlate these oil families to stratigra phic units that sourced them based on distinctive molecular characteristics . Three distinctive hydrocarbon systems have been identified within the nor theastern Timan Pechora basin. Hydrocarbons, both oil and gas, are found in elastic and carbonate reservoirs from the Lower Silurian to the Triassic, Three major oil families have been identified based on physical properties, gas chromatography: liquid chromatography, and gas chromatography-mass spe ctrometry. Family A oils are found in Permian-Silurian reservoirs within th e Sorokin swell and Upper Devonian reservoirs within the eastern and wester n edges of the Khoreyver depression. This oil family is sourced from an Upp er Devonian bitumen-laminated carbonate mudstone informally known as the do manik facies. Family B oils are found only in Upper Devonian reservoirs wit hin the central Khoreyver depression. This oil family is most likely source d from Upper Devonian hypersaline marine mudstones with significant bacteri al input. Many of the family B oils were generated at temperatures less tha n that for peak oil generation. Family C oils are found in Carboniferous-Lo wer Devonian reservoirs within the northern Sorokin swell. This family is s ourced from marine mudstones that have Gloecapsamorpha prisca, as well as o ther marine algae, present. Organic-rich Lower Devonian and Silurian shales contain similar molecular characteristics and are potential sources for th e family C oils.