DEVELOPMENT METHOD FOR OIL DEPOSIT HAVING OIL-WATER ZONES Russian patent published in 2006 - IPC E21B43/20 

FIELD: oil production, recovery methods for obtaining hydrocarbons, namely by oil displacing with water.

SUBSTANCE: method involves drilling horizontal producing wells in productive pool and extracting oil through producing wells. Productive pool is drilled from pool roof with at least one conditionally horizontal well having 75-85° bore inclination angle to vertical line in down-slope contour. Angle of bore inclination provides well bottom location near oil-water contact out of high pressure gradient field having pressure gradients of not more than 0.25 MPa/m. The well is cased and production string is lowered in well up to well bottom. One string section is formed as fiberglass pipe having 10-15 m length and arranged at pool roof. Then 30-70% of productive pool is penetrated beginning from pool roof. As well watering increases oil is finally withdrawn by drilling the second inclined and/or horizontal bore, which is cut from fiberglass string section.

EFFECT: increased efficiency of oil deposit having thin pool development, improved well deliverability and oil recovery due to reduced volume of produced water, simplified structure and reduced costs of producing well drilling.

1 dwg, 3 ex