Abstract: Oil Families and Their Potential Sources in the Northeastern Timan Pechora Basin, Russia
ABRAMS, MICHAEL A., ANNA M. APANEL, OLGA TIMONSHENKO, and NATALIA KOSENKOVA
Oil and rock samples were collected throughout the northeastern Timan Pechora Basin to identify key oil families and to correlate these oil families to stratigraphic units which sourced them based upon distinctive molecular characteristics. This largely Paleozoic basin lies between the uplifted Timan Ridge and the Hercynian fold system of the Ural Mountains. Hydrocarbons, both oil and gas, are found in clastic and carbonate reservoirs that range in age from Early Silurian to Triassic. Three major oil families have been identified. The "Classic Domanik" family is found in Late Devonian, Early Devonian, and Silurian reservoirs within the Sorokin Swell and east-central Khoreiver Depression. This oil family is sourced from a Late Devonian bitumen-laminated carbonate mudstone informally known as the Domanik facies. The "Chemically Stressed" family is found only in Late Devonian reservoirs within the Central Khoreiver Depression. This oil family is most likely sourced from Late Devonian strongly reducing, evaporitic carbonate marine mudstones with significant bacterial input. Many of the Chemically Stressed oils were generated at lower than peak maturity. The "Sawtooth" family is found in Carboniferous, Late Devonian, and Silurian reservoirs within the northern Sorokin Swell. This family is sourced from marine mudstones dominated by a single organism, Gloecapsamorpha prisca. Organic rich shales from the Lower Devonian and Silurian contain similar molecular characteristics and are potential sources for the Sawtooth oils.
AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria