The article considers the prediction of permeability of terrigenous-carbonate rocks based on well logging data. According to the lithological description of the core and the filtration and capacitive properties, the rocks are divided into lithological types (lithotypes). These lithotypes are divided into reservoirs and low permeability non-reservoirs. Non-reservoirs are represented by rocks with a high content of clay and anhydrite material, microcrystalline and micro-fractured dolomites. The reservoirs are represented by sandstones, aleurolites and dolomites. The permeability of terrigenous rocks, with the same values of porosity, decreases with a decrease of grain size and an increase of the content of minerals with high dispersion, sorption and ion exchange. Permeability of carbonate rocks depends on the structure of their void space. According to specific electrical resistance and nuclear-magnetic resonance studies of core samples, it was found that the presence of large cavities reduces the hydrodynamic connectivity of voids and the permeability of rocks. The considered features were taken into account when predicting permeability based on well logging data through a synthetic parameter – flow zone indicator (FZI). To determinate this parameter, a three-dimensional relationship is proposed that connects the FZI from core with geophysical parameters. The results of FZI calculation are consistent with core determinations. Calculating the permeability coefficient using the FZI more accurately reproduces core measurement than calculating using the standard dependence on the porosity coefficient. During well testing, the largest inflows of formation fluids were obtained from the most permeable intervals identified by this method.
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