Study of the geochemical processes of radionuclides of oil and gas fields

Ural State Mining University, 620144 Ekaterinburg, Russia

^* Corresponding author: groupnedra@mail.ru

Abstract

The objects of study of the geochemical processes of radionuclides are deposits of the West Siberian Plate, the distribution of radioactive elements in the areas of the Tyumen oil and gas region. In the process of work, the chemical composition of sedimentary rocks was investigated, and the mass fractions of uranium, radium, thorium, potassium, and other chemical elements were determined. Data on the distribution of radionuclides in individual wells and areas were considered, correlation diagrams of geochemical specificity were constructed. To determine the mass fractions of uranium, radium, thorium, potassium, and other chemical elements, gamma spectrometric, neutron activation, X-ray spectral, and laser-luminescent measurements were used. In order to control the measurement results, the determination of uranium in the samples was duplicated using the delayed neutron method in a specialized facility. The accuracy of uranium determination, estimated from independent measurements, was ~ 6.4% (rel.). The radioactive equilibrium is shifted towards uranium, which indicates an increase in the mass fractions of naturally radioactive elements in the raw of sandstones -sandstone-siltstone open pits - siltstones. The increase of the level of natural radioactivity in the direction from sandstones to siltstones is explained by the difference in brittleness between quartz and grains of active accessories, which indicates a stable ratio between radium and uranium in the sandstones-siltstones in relation to the considered areas of the Tyumen region.