METHOD OF DEVELOPING HIGH-VISCOSITY OIL DEPOSITS Russian patent published in 1999 - IPC

FIELD: oil and gas production. SUBSTANCE: deposits are opened by uniform triangular grid of production wells to form 13-point development surface elements, each concentric raw embracing 6 wells. In the central well, horizontal holes are drilled from individual windows over specified packets of beds belonging to development object and having length about 1/3 distance between the grid wells. Oil production and pumping-in of heat carrier are carried out cyclically with the same amount of heat carrier in each cycle. Each cycle is accomplished in three phases. In the first one, heat carrier is pumped in through central well and through every second peripheral production well. Remaining peripheral production wells are used to take off product. Then central well and peripheral wells receiving heat carrier are switched over to oil production and those producing oil are switched over to receive heat carrier. In the third phase, all production wells produce oil. Distribution of heat carrier between central and peripheral wells is made in accordance with relevant math expressions. EFFECT: increased oil recovery of deposit.