Published online by Cambridge University Press: 01 May 2009
The Soviet Arctic extends 6700 km from the border with Norway, on the west, to the border with the United States, on the east. The region contains the largest unexplored shelf area on earth – approximately 3917000 km2. Of the several onshore petroleum-bearing basins, at least two extend into the offshore – the Timano-Pechora basin, which passes beneath the Barents Sea, and the West Siberian basin, which includes much of the Kara Sea. The Laptev and East Siberian Seas seem to be underlain by separate offshore basins, possibly unrelated to any onshore. The Chukchi Sea is geologically a part of the Alaskan North Slope. The Vilyuy basin, along the Vilyuy and Lena Rivers, does not extend offshore. Only small basins are present along the Pacific shore; of these, two have petroleum potential – the Khatyrka basin which passes eastwards into the Navarin basin of the Bering Sea, and the Anadyr' basin which joins the St Lawrence basin. Peripheral to the Arctic, but of great importance relative to several Canadian Arctic basins, is the Irkutsk amphitheatre in which the main hydrocarbon accumulations are Proterozoic.
Of the three largest onshore basins, the West Siberian is the greatest, with major production from Lower and Middle Cretaceous, and smaller production from Upper Jurassic and Upper Palaeozoic rocks. The major production from the Timano-Pechora basin is from the Middle Devonian and Upper Carboniferous–Lower Permian; minor production is from the Silurian, Lower Devonian, Upper Devonian, Lower Carboniferous, Upper Permian and Triassic. Production in the Vilyuy basin – all of it gas – is from Lower and Middle Jurassic, Triassic and Permian. Although non-commercial, known potential production from the Nordvik area is from Triassic and Permian sandstones; that from the Khatyrka basin is Oligocene and that from the Anadyr' basin is Miocene. The potential of the Soviet Arctic is huge, with major oil reserves and the largest known gas reserves on the earth.