Equilibrium regions validation to build reservoir static models in San Jorge Basin. "Adding value to making decisions" Since the beginning of the hydrocarbon exploration and production times, conceptual models as a preliminary visualization, constituted a key point in the understanding of a field. The application of conventional methodology for reservoir characterization has some limitations in San Jorge Basin (CGSJ) due to particularities in the architecture and composition of its sedimentary column. Sur Piedra Clavada (SPC) field shows the characteristics of a multi-reservoir field, common within this basin, while having most of its hydrocarbon accumulations and production concentrated in Bajo Barreal formation. Evidence of vertical connectivity between different sand bodies was found by analyzing their location within the stratigraphic column, measured formation pressure and fluid distribution. The original study, performed in year 2009, pointed to identify interconnected sections of the column by means of pressure gradient behavior under original conditions applying a calculus procedure. Sedimentary complexity required a vertical and horizontal refinement, concluding in the presence of twenty-one equilibrium regions finally verified. Each one of them was described by means of its corresponding facies, fluid contacts and saturations. Since 2009, more than 40 new wells were drilled in the area allowing validation techniques application to support the equilibrium regions recognition methodology originally applied. The validation analysis concluded that the calculus procedure proved to be a powerful methodology for establishing the first equilibrium-region hypothesis for the complete Bajo Barreal formation. Proved the existence of @75 % of the original equilibrium regions, new appraisal well locations were proposed to continue quantifying hydrocarbon accumulations of this mature field.