Lithofacies Model of Riphean Formation of Yurubcheno–Tochomskoe Field

Carbonate oil reservoirs have complex structure and vertical and lateral variations of properties. Carbonate rocks are highly transformed by secondary processes, which may entirely change the structure of rocks and the cavity geometry. A geological model of carbonate oil reservoir must take into consideration all of the following factors: the detailed lithologic analysis, rock characteristics, cavities structure and reservoir distribution in section and by area. This article reveals how the complex studying of material (core samples, thin sections analysis) may help to predict the productivity of carbonate reservoir, for example Yurubcheno-Takhomskoe oil field, esp. when geophysical measurements, e.g. seismic or logging, are non-informative for oil content estimation. Different type of dolomite were defined. Intraclast dolomite is the main type of dolomite rocks with additional volume. Well tests confirm that assumption. Intraclast dolomite embeds in the top of sedimentology cycle. As the result of the investigation the productive zones were delineated