METHOD OF DEVELOPING OIL OR OIL-GAS CONDENSATE MINEFIELDS AT LATE STAGE Russian patent published in 2009 - IPC E21B43/00 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil industry, and can be used when developing oil or oil-gas condensate minefield having wide production history or being at the late stage of development. According to the method, product is taken through production wells, operating agent is injected through pressure wells, logging surveys of wells are performed, formation fluids and core are analysed, data on operation of production and pressure wells is analysed, a geological hydrodynamic model of productive fields is built, areas with residual saturation of productive fields are defined, actions regarding additional extraction of deposits and prognosis of product extraction product indices on geological hydrodynamic model is prepared, and further development of the field according to geological hydrodynamic model data is performed. In addition, there carried out are seismic investigations of the minefield and logging surveys of wells in operation, covering 20-25% of existing well stock, and actual values of porosity, permeability, oil-water contact position, oil-gas contact position, and residual oil-gas condensate saturation of layers are determined. New wells are bored or surface holes are drilled for wells with recovery of core in amount of 0.5 -1.5% of existing well stock, and properties of productive layers are determined as per the core. Downhole fluid samples are taken in amount of 3-5% of the existing well stock, and complex analysis thereof is made. Thermal hydrodynamic surveys of wells of not less than 60% of existing well stock are carried out. At the late stage of formation development there prepared is a database according to current parameters and there built is geological hydrodynamic model of the field development status, which considers technogenic object changes with its monthly adaptation according to parameters of wells' operation for the last 1-3 years. There defined is a state, volumes and distribution of technogenically changed hydrocarbon reserves of the minefield. There predicted are different versions of development with regard to present thermal hydrodynamic conditions, characteristics of formations and saturating fluids, and the most effective version is implemented on the minefield.

EFFECT: improving oil-gas condensate production rate of the minefield having wide production history at the late stage.

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