METHOD OF FORMATION WATER SHUTOFF IN HORIZONTAL OIL WELLS (VERSIONS) Russian patent published in 2002 - IPC

FIELD: oil producing industry, particularly, methods of formation water shutoff. SUBSTANCE: according to the first version, method includes drilling of multihole oil well with horizontal holes in one vertical plane. One of horizontal holes is located in oil-bearing part of formation, the second horizontal hole is located in water-bearing part, below water-oil contact; side-tracking of the third horizontal hole is carried out at level of water-oil contact between existing holes. In this case, cone of depression produced by each hole does not reach the nearest hole. According to the second version, method includes drilling of multihole oil well with horizontal holes in one vertical plane. One horizontal hole is located in oil-bearing part of formation, the second horizontal hole is located in water-bearing hole of formation. Side-tracking of the third hole is performed in water-oil transition zone between existing holes. In this case, depression cone produced by the third hole embraces the entire transition zone in height. EFFECT: simplified regulation of position of water-oil contact in formations with bottom water. 2 cl, 3 dwg