The Handbook discusses the features of geological exploration of oil and gas fields during their commercial development. It contains detailed information on the conditions of occurrence of oil, gas and water, hydrogeology of oil and gas fields. The book contains the energy characteristics of the oil and gas reservoirs, the geological justification for penetrating the pay zones, and the methodology for estimating oil and gas reserves. In addition, much attention is paid to the geological foundations of the development and subsequent use of oil and gas fields. Designed for specialists in oil and gas geology, teachers, graduate students and students of higher educational institutions of geological profile.