METHOD FOR STUDYING THE CORE OF TERRIGENOUS ROCKS Russian patent published in 2023 - IPC G01N3/32 E21C39/00 

FIELD: petrophysical research.

SUBSTANCE: invention can be used to determine the conditions for the flow of elastic and irreversible deformations of rocks in drained formations in the development of oil and gas fields and the operation of underground gas storages (UGS). A core of terrigenous rocks is saturated with fluid and placed in a core holder. The core and fluid in the core are brought to reservoir conditions and the deformation properties of rocks are determined with a stepwise change in the initial pressure in the core. At the same time, the deformation properties of rocks are determined with a cyclic stepwise decrease and the same increase in pressure in the core with an increase in this value at each cycle, the core deformation and the amount of pressure reduction in the core are recorded, at which the core deformation, determined with a decrease in pressure, becomes different from the deformation core determined at the same pressure increase in the core. According to the such minimum decrease in pressure, the pressure value in the core is determined, below which the deformation of the rocks of the core passes from elastic to irreversible, and according to the maximum decrease, at which there is no deformation of the rocks at the stage of pressure increase, the pressure is determined, below which the deformation of the rocks becomes only irreversible.

EFFECT: ability to assess the feasibility of constructing geodynamic polygons in UGSs and to determine drawdowns on the reservoir when defining operating conditions of production wells that do not lead to the destruction of reservoir rocks in the bottomhole zone.

1 cl, 1 dwg