Six American geophysicists spent three weeks in the U.S.S.R. during the early fall of 1965 as members of an exchange delegation in petroleum geophysics set up under the terms of a treaty on technical exchanges between the U. S. and the U.S.S.R. The group visited eleven different activities located in four cities, Moscow, Oktyabr'skiy, Krasnodar, and Leningrad. These activities included a number of geophysical and geological research institutes, the Moscow State University, and the Gubkin Institute. The principal difference between exploration geophysics in the U.S.S.R. and in the Western countries is the great emphasis in Soviet oil exploration on regional studies as a preliminary to the more direct search for petroleum deposits. As a result of such emphasis, their exploration program involves much greater use than ours of long refraction lines, electrical prospecting, and aeromagnetic surveys with close line spacing. Reflection work follows conventional lines without such recent refinements as common depth point shooting, impact sources, or vibrators. A possible reason these newer field techniques are not used is that no processing equipment appears to be generally available for compositing signals from more than one tape on to a single channel. Seismic shear waves generated at the surface have given reflections from depths as great as 5,000 ft but they have thus far been used only on an experimental basis. A technique of recording “exchange” (PS) waves from earthquakes has been employed for mapping basement depths in regional investigations.

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