MULTI-FORMATION OIL DEPOSIT DEVELOPMENT METHOD Russian patent published in 2025 - IPC E21B43/20 

FIELD: mining.

SUBSTANCE: invention relates to the oil industry, in particular to methods for developing a multi-formation oil deposit using a branched horizontal well and downhole pumping and can be used both at the early stage of development, and at the later one. Method of multi-formation oil deposit development includes drilling of branched horizontal well, start-up of well for production. Branched horizontal well is drilled with length of shafts of 250-350 m in productive formation with oil-bearing thickness of 4.5-7.0 m, oil is extracted, water cut of the extracted product is measured. With water cut of 98% or more branched horizontal well is transferred into injection well, main horizontal shaft is isolated from the side horizontal branches and from the underlying water-bearing donor bed, a working agent is pumped into the branched horizontal well for five days with a constant flow rate equal to 1.2-1.4 of the volume of the product extracted from the surrounding production wells, then performing the process exposure – for one day the branched horizontal well is in idle time, the working agent injection cycles to the branched horizontal well are repeated. When the water cut of the product increases to 80% of the initial water saturation, pumping is stopped, and after the water cut of the product is reduced to 10% above the initial water saturation, pumping of the working agent is resumed, after stopping injection of working agent for up to 60 days, determining average water cut of products in branched horizontal well, which is taken as the initial water saturation, and the working agent pumping cycles are continued according to the same pumping principle for five days and process holding for one day, but based on the new value of the initial water saturation.

EFFECT: providing maximum and uniform oil displacement from the deposit, increasing well productivity due to using downhole pumping to branched horizontal wells.

1 cl, 1 dwg