The article considers the possibility of increasing the efficiency of oil recovery in one of the fields in Iraq, which has been actively developed for several years using the waterflooding process. The object of development is the Mishrif reservoir with a fracture reservoir. At the same time, a decrease in reservoir pressure has been noted recently due to insufficient compensation of reservoir energy by pumped water. Based on the complex data analysis from well logging, aerospace geology, well testing, well development and operation indicators, conclusions are drawn about the emerging negative trends in field development associated with changes in fracture configurations, which in turn is due to a decrease in reservoir pressure below their closure pressure. To take into account the distribution of the volume and permeability of the cracks, the previously used methodology for constructing a model of the volumetric network of cracks tested at the objects of the Perm region and the Republic of Komi, adapted in the course of research to the specific conditions of the field under consideration. An analysis of the results showed the possibility of applying the methodologies used at carbonate sites in Russia for the conditions of Iraq. Based on the constructed model of a network of fractures, analysis of changes in the permeability of the formation during the development and analysis of other technological indicators, specific technological recommendations have been issued for restoring the reservoir pressure and for choosing the operating mode of the wells, as well as for placing additional production and injection wells. A feasibility study of the proposed recommendations has been made. Taking into account the revealed dynamic dependences of permeability on pressure, the location of fracture zones, can significantly reduce the well stock and capital investment at the research object.
References
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