METHOD FOR EXPLOITATION OF A DEPOSIT WITH POROUS-CAVERNOUS-FRACTURED RESERVOIR BY HORIZONTAL WELLS Russian patent published in 2022 - IPC E21B43/16 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the oil and gas industry and can be used in the development of oil deposits by horizontal wells with water displacement. A method is proposed for exploiting a reservoir with a porous-cavernous-fractured reservoir by horizontal wells, including drilling horizontal production and injection wells located one above the other in the productive formation of the deposit, analyzing the cores to determine the pressure of the integrity of the roof of the formation, making a preliminary exposure to a pressure below the pressure of breaking the integrity of the roof, injection the displacing agent into the injection well and the selection of products from the production well. The upper production well is drilled closer to the reservoir top and above the oil-water contact (OWC), and the lower injection well is drilled closer to the formation bottom and below the OWC level. The analysis of cores also determines the pressure of violation of the integrity of the sole of the formation, compares the pressure of violation of the integrity of the roof and the sole of the formation, determining the least. The secondary opening of wells is carried out using directional opening, and the upper well is opened towards the roof, and the lower one - towards the sole. For preliminary impact, pressure is increased in a well remote from the roof or bottom of the formation with the lowest pressure of integrity damage to a pressure of 5-10% less than the lowest pressure of violation of the integrity of the roof or bottom. After that, the insulating composition is injected in another well to form an impermeable first screen between this well and the top or bottom of the formation. After technological soaking sufficient to harden the screen, the pressure is increased in the well remote from the sole or roof of the formation to a pressure 5-10% less than the pressure of violation of the integrity of the sole or roof. After that, the insulating composition is injected in another well to form an impermeable second screen between this well and the bottom or top of the formation. After a technological exposure sufficient to harden the second screen, an additional secondary opening of both horizontal shafts is performed to increase the filtration area. As a displacing agent, fresh or mineralized water is used, pumped through an injection well with a pressure not exceeding the smallest pressure of destruction of the roof or formation outside the corresponding screen.

EFFECT: expanding the scope of application by providing the possibility of producing also light oil and increasing the efficiency of the implementation of the method by arranging appropriate impermeable screens between the upper well and the roof, as well as between the lower well and the sole.

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