Geodynamic processes, hydrocarbon migration and their occurrence in geophysics

Abstract

The paper shows that in the oil deposits formed in the Earth crust, due to the overpressure hydrocarbon components migration to the sedimentary cover and penetration to the field occur. As a result of vertical hydrocarbon migration in the oil and gas fields, a subvertical zone differing by its physical properties from the environment is formed. Such a subvertical zone affects geophysical, geochemical and logging data as well. Therefore, while migrate to the near-surface zone, hydrocarbons interact with a complex of rocks of sedimentary cover. As a result of impacting of fines forming hydrocarbons with the complex of subsurface rocks, a part of hydrocarbon flow energy transforms into the fluctuations of minor particles of subsurface rocks, and the other one, in the result of atoms and molecules impact - into the irregular molecule motion. A part of mechanical energy of moving particles transforms into another - thermal type of energy, as a result of which the environment gets “warmed”. Herewith, the temperature in near-surface zones differs from environment. Therefore, in the oil and gas fields in subvertical zones a heterogeneous area differing from the environment by geophysical, geochemical and other characteristics is formed. Based on the research data carried out by numerous specialists, it was justified that the changing of geophysical parameters is affected not only by oil-gas field, but near-surface zone as well. This feature is recommended to consider in the analysis of geophysical data.