Assessment of Sakhalin shelf reservoirs by geomechanical modeling

Abstract

Background. The complex tectonic structure of the Sea of Okhotsk shelf, its high geodynamic activity and the presence of non-anticlinal traps in plays requires special technologies for studying the secondary filtration-volumetric parameters of reservoirs. The prediction of the location and direction of open fractures is complicated by their small size. Such fractures are frequently too small to be detected by such conventional logging or seismic instruments. The detection of fracturing by seismic methods is impossible in principle; however, some high-resolution logging tools are capable of detecting fractures under favorable circumstances. In cases where neither logging nor seismic exploration can detect fractures, geomechanical modeling can be used. Geomechanical modeling makes it possible to predict the effective porosity and permeability in the сrosshole space.Aim. To assess the geomechanical properties and secondary permeability parameters of the Sakhalin shelf reservoirs.Materials and methods. The ROXAR reservoir modeling software was used to assess the secondary filtration-volumetric parameters of the Sakhalin shelf reservoirs.Results. The modern shear stress field was revealed. The permeability of each stratigraphic horizon was calculated. The filtration capacity of local structures was established.