DEVELOPMENT METHOD OF OIL DEPOSIT WITH HORIZONTALLY BRANCHED WELLS Russian patent published in 2015 - IPC E21B43/20 E21B43/14 E21B43/30 

FIELD: oil and gas industry.

SUBSTANCE: according to the method direction of reservoir-scale fractures is defined. Development elements are formed by drilling vertical and/or inclined injectors as per square grid and horizontally branched wells (HBW) with rounded borehole endings. HBW boreholes are placed around injectors. Pumping of working agent is done through injectors and recovery of products through producers. At that each development element is formed by four injectors so that edges of elements are oriented at angle of 40-50° to predominant direction of natural reservoir-scale fractures. Distance between edges of the neighbouring elements is equal to length of 3L, where L is half length of the element edge. Distance between injectors inside the element is accepted as 2L. At each element there are two perpendicular dual producing HBW. Each of these wells is S-shaped in plane, where rounding shape is the borehole end. Entries of HBW to the productive stratum are placed in the central part of the element. Each horizontal borehole is led in different oil-bearing interlayers so that in plane they envelope the opposite injectors with radius of L and semicircle length of π·L, where π=3.14. Length of one HBW borehole is L·(π+1).

EFFECT: increasing sweep efficiency and oil recovery rate from productive stratum of the oil deposit.

2 ex, 3 dwg