At the moment, hydrocarbons confined to carbonates are the target of increasing interest and are the drivers of oil production growth and maintenance. The involvement of carbonates into production requires the use of new approaches due to poor reservoir properties and complex geological structure. The article discusses the use of lithofacies modeling for carbonate development optimization in Borovskoye field, located in the Samara Region. Dividing reservoirs into petroclasses depending on petrophysical differences of voids is the new differentiated approach to geological modeling. The Borovskoye field is multihorizon and multi-domed. The main productive formation is Bashkirian stage (reservoir A4), which contains most of residual recoverable reserves. The reservoir A4 is defined by poor PVT characteristics and poor continuity of rocks in terms of thickness, quality and also lateral continuity. The results of the research work on creating a unified petrophysical model of Bashkir carbonates in Bashkortostan oilfields were used as a basis for refining the petrophysical dependencies and constants of A4 reservoir. As a result three petrophysical types of A4 reservoir were distinguished: fracture-porous, vugular-porous and porous. This division of A4 reservoir into petroclasses is confirmed by the differences in flow rates and cumulative oil production of wells. The choice of the optimal production case of A4 reservoir of Borovskoye field was based on reservoir simulation model adapted to the production history. Based on the concentration of the main part of residual recoverable reserves and appropriate petrophysical reservoir type the pilot area of the field was chosen for future expansion on the field.
References
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