Devonian layer terrigenous deposits reserves recovery status was carried out. It is shown that, as a result of long-time development processes, the residual reserves have localized in the roof part of monolithic benches, or in low permeability benches and interlayers. These results are verified by the oil saturation assessment during the operation drilling and the stock restoring by sidetracking. The 80 drilled into the D2ps Tuymazinskoye deposit wells’ operation records show that the initial oil recovery does not exceed 5-6 t/24h and the initial water-cut is more than 85 per cent. The cause of the low production rate is coning, i.e. raising the water-oil sector surface along the borehole axis. In order to assess contact or floating area's size impact on the basic parameters of the reserves recovery, the D2ml Tuymazinskoye oil field Devonian layer terrigenous deposits reservoir compartments having a different floating zone share in the site area recovery analysis has been made. The resulting dependence of the oil recovery factor on the contact space areas shows that the zones with the maximum size contact areas are characterized by low oil recovery factor and poor recovery efficiency. It is shown that, for the floating areas, the recovery is characterized by unfavorably high initial water cut values and its intensive growth in oil recovery range of 0.1 to 0.3. The high accumulated floating areas water-oil ratio tends to be accompanied by high oil well water-cut and a high watering time of the recovered product from the beginning of the site development. To obtain the residual oil reserves higher recovery, a technology has been developed to extract oil reserves from the roofing area, which is based on the phased formation drilling. Multiple regression equations have been worked out to calculate the oil cone formation periods and the subsequent water cone formation period in the contact areas, depending on the reservoir geological and physical parameters and the rate of fluid withdrawals.
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