METHOD OF DEVELOPING TWO OBJECTS OF DIFFERENT STRATIGRAPHIC ACCESSORIES Russian patent published in 2018 - IPC E21B43/16 E21B43/20 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas production industry, namely to development of a multi-object deposit. Method of developing an oil field includes drilling of obliquely directed production and injection wells, selection from production wells and injection of a displacing agent into injection wells. Before drilling wells, zones of overlapping in plan two oil-bearing objects of different stratigraphic affiliation with a vertical distance of 100 to 400 m are determined, isolate zones of oil-bearing objects with a thickness of 0.5 to 50 m. At a thickness of oil-bearing objects from 0.5 to 4 m, at least one vertical well is drilled and oil-bearing objects are simultaneously developed in a separate way. At a thickness of oil-bearing objects from 4 to 50 m, horizontal wells (HW) are drilled. First, the HW is drilled to the lower oil-bearing facility. Entry points to the oil-bearing objects according to the HW are in plan separated from each other by half the distance of the grid along the drilling path. Drilling is performed with a zenith angle of 68–80° on the roof of the upper oil-bearing object. After the fall of the zenith angle, the zenith angle is again set to 74–83° on the roof of the lower oil-bearing object and enter the oil-bearing object 12 m below the roof along the trunk. Then, geophysical surveys of wells (GSW) are carried out, the roof hypsometry is clarified and the casing string is lowered. After isolating the cavernous space, GSW is carried out to determine the tightness of the cavernous space. After drilling a horizontal trunk with a smaller diameter along the length equal to the grid distance, with an outlet in an oil-bearing facility at 89–91° depending on the structural features of the topography of the roof of the lower oil-bearing object in the direction to the slaughter in plan, and in the zones with plantar water the trunk is located above the oil-water contact (OWC) by 10–45 m, and in zones without plantar water – above the dense underlying rocks by 2–46 m. Horizontal trunk is filled with a hydro-emulsion solution. Then, the upper horizontal trunk is drilled in the upper oil-bearing object from a removable wedge-deflector. Horizontal barrel is cut over the roof or within the oil bearing object and the drilled with a smaller diameter and the same azimuth as the lower trunk, with an acceptable divergence from 0 to 7° and with an exit in the facility at 89–91° depending on the fall or rise of the relief of the roof of the oil-bearing object in the direction of slaughter in plan. Moreover, the trunk is located above the OWC at 10–45 m in zones with plantar water, and in zones without plantar water it is higher than dense underlying rocks by 2–46 m. Trunk is left open or planted with a filter, depending on the petrophysical characteristics of the oil-bearing rocks. Well is equipped with equipment for simultaneous-separate operation and is put into operation.

EFFECT: proposed method allows to increase oil recovery factor, and also to shorten development term due to development of reserves of two objects with a single well grid.

1 cl, 2 dwg, 1 ex