Choosing a strategy for the development of hard-to-recover oil reserves based on integrated modeling

Abstract

The article presents an integrated approach to the selection of the most optimal option for involving in the development of oil reserves confined to thin-layered clay-bearing reservoirs, based on integrated modeling. Previous studies of facies, geological and petrophysical reservoirs of the reservoir under consideration using a newly sampled core made it possible to reconsider the prospects for oil production, which was previously considered unprofitable. The use of the spectral method made it possible to take into account the high anisotropy of properties and achieve a highly detailed geological model, on the basis of which an increase in the initial geological reserves (IGZ) by more than 50% and their belonging to the category of hard-to-recover (TRIZ) is justified. The assignment of the deposit to the category of TRIZ made it possible to apply a preferential coefficient to the mineral extraction tax, which increased the economic attractiveness of the project. To reduce the risk of involvement of the underlying water-saturated interval, studies of the elastic-deformation properties of the reservoir rocks were carried out, on the basis of which a geomechanical model was built to select the optimal parameters for the hydraulic fracturing (HF) operation. To select the optimal location of production and injection wells, as well as the parameters of their injection using a hydrodynamic model, a feasibility study of development systems using directional (DW) and horizontal wells with multi-stage hydraulic fracturing (HW+MHF) was carried out. An integrated approach made it possible to develop solutions to more than double the oil recovery factor (ORF) and net present value (NPV) of the project.