483 
The Black Sea and the Sea of Azov are part of a major intracon- 
tinental basin. The Black Sea depression contains sedimentary rocks 
up to 15 kilometers thick. The Mesozoic and Cenozoic deposits in 
the Karkinit deep of the Black Sea basin offer the best hydrocarbon 
potential. They vary from 5 to 7 kilometers in thickness. Exploration 
will be concentrated along a series of local structures in the 
Cretaceous and older Teritiary rocks.® 
In the Sea of Azov, the Azov-Berezan bank on the mid-Azov uplift 
is the best oil and gas prospect. The rocks in this area are of 
Cretaceous and early Cenozoic age. 
NORTHWESTERN AND ARCTIC U.S.S.R. 
More than 70 percent of the Soviet shelf area fronts the Arctic 
Ocean. Much of it is poorly explored geologically, but sufficient data 
are avilable to show that the Arctic shelves are associated largely 
with ancient Precambrian platforms. Mesozoic and Cenozoic sub- 
sidence and sedimentation on the Arctic shelves have enhanced oil 
and gas potential and local tectonic characteristics often favor large 
hydrocarbon accumulations, especially in the gently dipping platform 
sedimentary rocks that extend from the land onto the shelf. This 
potential is supported by the major discoveries in northern Siberia 
and in Alaska. 
The Russian sector of the Baltic Sea contains the Baltic synclinal 
basin whose flanks dip moderately from the margins into the bowl- 
like depression. The rock section is predominately lower Paleozoic. 
Approximately 60 prospective oil and/or gas structures have been 
identified onshore and offshore. Oil shows are numerous and several 
oil fields have been discovered onshore. The increasing stratigraphic 
thickness offshore, with favorable structure, indicates that even larger 
subsea reserves could be present. Source beds, volume of reservoir 
rocks and the density of local structures appears to increase seaward.’ 
The Arctic Barents Sea, opening on the Arctic Ocean, is about 
1,405,000 square kilometers in area. About one half of this expanse 
is deeper than 200 meters. The sea is underlain by fold belts of 
several ages, each of which is the basement of a younger rock cover. 
The Barents-Pechora synclinal basin of the Russian platform occupies 
a large part of the southern Barents Sea. Farther north is the North 
Barents synclinal basin which is a part of the Barents-Kara platform. 
In the Barents Sea, seismic surveys have determined the present of 
all the basic requirements for an oil and gas bearing complex.* The 
principal hydrocarbon objectives are the Devonian rocks. 
In the Pechora Sea, the southeastern part of the Barents Sea, exten- 
sions of anticlinal axes occur which have been traced from the 
northern part of the onshore Timan-Pechora oil and gas province. 
In the offshore zone, Mesozoic and Tertiary sediments total 12 to 
15 kilometers in thickness. The white (Beloye) Sea to the west in- 
cludes a portion of the Mezen basin, but much of the sea lies within 
the unproductive Baltic shield. 
§ Ibid. 
7 Ibid., pp. 240-241. 
é Eremenko, N. A., Ovanesov, G. P., and Semenovich, V. V. Status of Oil and Gas Prospecting in 
U.S.S.R. in 1971. American Association of Petroleum Geologists Bulletin, V. 56, no. 9, September 
1972, p. 1716. 
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