ABSTRACT Russian patent published in 2009 - IPC E21B43/02 E21B43/16 

FIELD: oil and gas production.

SUBSTANCE: invention refers to oil and gas industry. It facilitates decrease of penetrability of borehole environment of massif of rock due to change of electric-physical properties of rock by means of successive layer-by-layer mudding from top downward and from the centre of the well to periphery. There is determined value of duration of pulse droop, the reverse value of which is maximal frequency of electric current. Further borehole environment is effected with pulses of electric current step-by-step successively diminishing frequency of electric current from maximal value to a value close to zero; also penetrability of conducting clusters of borehole environment of massif of rock is decreased from the centre to periphery by means of mudding porous and capillaries of environment. Further effective values of current strength and voltage are measured in borehole environment and gradients of electric resistance are determined. When gradient of electric resistance equals zero, current strength is increased. At positive value of electric resistance gradient current strength is not further increased; effecting is carried out at the same value of current strength, while at negative value frequency of electric current is diminished.

EFFECT: initially there is determined maximal value of electric current frequency facilitating conducting maximal amount of electric current pulses in near surface layer of borehole environment by means of influencing it with electric current pulse.

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