INFLUENCE OF NATURAL FACTORS OF SUPPORTING RESERVOIR PRESSURE AT THE LATE STAGE OF DEVELOPMENT OF GAS CONDENSATE FIELDS

Abstract

The object of the research is natural factors that can affect both the maintenance of reservoir pressure in the process of developing gas condensate fields and the recovery of depleted deposits. Such factors include: waterflooding of deposits, subsidence of the surface, elasticity of rocks, water and gas, initial gradients of reservoir pressure in deposits, capillary forces. When studying the recovery of reserves in depleted gas condensate fields, it is necessary to take into account the influence of the above factors on the maintenance of reservoir pressure in order to identify the volumes of gas that flow from deep horizons (external sources). The paper shows the dynamics of waterflooding volumes and average reservoir pressures over the years. It is emphasized that waterflooding does not significantly affect the maintenance of reservoir pressure. Correlation dependencies of waterflooding volumes over time and the dependence of waterflooding volumes on reservoir pressure are given. An original system for calculating the volume of the water pressure system is proposed for the purpose of forecasting further waterflooding of deposits. The influences of all the above factors on the process of maintaining reservoir pressure are taken into account. It is shown that for the Shebelinsky GCF, all these factors do not significantly affect the recovery of reserves. The influence of capillary forces and evaporation of water in deposits on the development processes from the point of view of maintaining reservoir pressure at the late stage of GCF operation is studied.