The Baykit Region coincides with the Baykit Anteclise and occupies about 120.000 square kilometres in the southwestern sector of the Siberian Platform in the Krasnoyarsk Region. The Baykit Anteclise is bordered to the west by the Yenisei Ridge, and to the north and south by the Kureyka and Sayan-Yemsei syneclises, respectively. To the east it is separated from the Nepa-Botuoba Anteclise by the Katanga Saddle. The thickness of the sedimentary cover ranges from 2.500 m to over 6.000 m. It comprises mainly Riphean, Vendian and Cambrian formations. Ordovician-Silurian, Upper Paleozoic and Triassic formations are less well developed. Lower Triassic intrusive trapps are widespread, individual intrusions are some 250 meters thick, but the overall thickness of sills is in many places exceeds 1,000 m. Systematic geological and geophysical exploration for hydrocarbons began in 1939. Upper Precambrian (Vendian and Riphean) as well as Lower Cambrian sections soon turned out to be prospective. In 1971, the first commercially significant flow of gas (105,000 cu In/day) was obtained from the top of the Riphean section. In 1976, commercial oil flows were also obtained in Riphean carbonate rocks. It is expected that future Baykit Region production of oil may reach 15-20 million tons per year. To date, over 40.000 kilometres of seismic profiles have been shot within the Baykit Region and over 60 exploratory/appraisal wells have been drilled. It would appear that major hydrocarbon accumulations are connected with the Riphean section but additional potential also exists within Vendian formations. Hydrocarbon generation and entrapment began in Vendian and Early Cambrian times. Permo-Triassic volcanism has only a limited effect on the hydrocarbon potential of this sector of the Siberian Platform. The petroleum geology of the area is, however, complex, as a result of a major phase of upwarping of the Baykit Anteclise during Post Triassic time, which resulted in extensive remigration of oil and gas and in the present-day diversities in the distribution of hydrocarbons in the area.