Radioactive Investigations of Oil and Gas Wells: A Textbook focuses on the radioactive methods used in the investigations of oil and gas wells, including radioactivity, nuclear reactions, and tracer method. The book first offers information on physical principles of the radiometry of wells and radioactive properties of rocks. Discussions focus on artificial transformation of elements and nuclear reactions; radioactivity and the law of radioactive disintegration; natural radioactivity; and induced radioactivity of rocks. The text then ponders on the methods of well geometry and radiometric apparatus. The publication examines the interpretation of results of measurements by the natural radioactivity method and working technique and interpretation of diagrams of the tracer method. Topics include selection of the radioactive isotope and technology of preparation of activated fluid and determination of absorbing strata and of communication between the strata outside the tubing in production wells and pressurized wells. The text is a dependable reference for readers interested in the radioactive methods used in the investigations of oil and gas wells.