oa Using Geomechanical and Fluid Flow Models to Predict Hydrocarbon Accumulation Zones

Location and redistribution of oil and gas deposits resulted by geologically long seepage of liquid and<br>gaseous hydrocarbons are determined significantly by the stress-deformed state of the Earth in upper<br>strata of 3-5 km thickness. Lithostatic and tectonic components make a decisive contribution to the<br>total stress field, with the tectonics effect changing stress essentially. So that accounting for the stress<br>anomalies of tectonic origin using geomechanical and fluid flow models enables characterizing<br>reservoirs and determining accumulation zones of hydrocarbons more precise and reliable.<br>The proposed approach to estimate palaeotectonic stresses within the framework of the elastic medium<br>theory includes the successive stages: (1) creation of the 3D structure velocity models of sedimentary<br>deposits using the seismic prospecting data; (2) estimation of boundary conditions to calculate tectonic<br>stresses by modeling of point displacements on layer boundaries due to long time deformations of the<br>sedimentary cover; (3) development and identification of 3D geomechanical models based on FEM<br>algorithms to calculate the tensor of tectonic and lithostatic stresses; (4) hydrodynamic evaluation and<br>contouring of hydrocarbon accumulation zones.