PROCEDURE FOR DEVELOPMENT OF OIL DEPOSIT Russian patent published in 2011 - IPC E21B43/16 

FIELD: gas-and-oil producing industry.

SUBSTANCE: procedure consists in analysis of geological structure, in plotting maps of roof and bottom of reservoir, in determination of absolute mark of water-oil contact, and in analysis of presence and zone of spread of impermeable interlayer between oil saturated and water saturated reservoirs. According to the invention rock is drilled rock for a production string of producers with a bit of a smaller diametre up to 215.6 mm in zones of spread of impermeable interlayer between oil saturated and water saturated reservoir. At sections of geological profile formed with mud shale, liable to fall, well borehole is made to the roof of a producing reservoir at zenith angle 70°. A production string is lowered into a drilled borehole and casing annulus is cemented. Upon hardening cement stone in annulus, a borehole is drilled with the bit of diametre smaller, than internal diametre of the production string at zenith angle 72-78°. Length of borehole below the lowered string is determined from an analytic expression.

EFFECT: increased waterless period of oil extraction and reduced water cut of extracted production at development of deposit due to avoiding exposure of water-bearing horizon.

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