Isotopic composition of uranium, water and oils of some oil-gas bearing provinces

A study into the pattern of distribution of uranium isotopes and 234U/238U ratio in the stratal waters, oils and water-bearing rocks of active water-exchange zones and oil fields in Central Asia, the Terek-Sunzha region, and the Volga region has been made. The radioactive ratios for stratal waters in the water-oil contact area are suggestive of an active isotopic exchange which leads to an isotopic equilibrium at the water-oil interface. The less intensive interphase isotopic exchange of uranium in the ''oil-rock'' system, as compared to the ''water-rock'' system, is indicative of a stronger link between uranium and oil, than between uranium and water. The deficit of the 234U isotope in the hypergenesis zone attests to the fact that, in the active water-exchange zone, depletion of rocks in 234U is currently taking place, while the values of 234U/238U ratios close to equilibrium, in water-bearing rocks indicate the absence of processes of intensive uranium migration in the rocks of the oil-gas provinces studied