A method is described for creating a petro-elastic model including receiving, at a computer processor, well log data; computing in situ rock properties; calculating dry frame moduli for a range of porosities based on a rock physics model such as a modified critical porosity model; performing fluid substitutions and computing elastic properties by statistical sampling for the range of porosities; creating a petro-elastic model in a seismic domain; and identifying and producing target hydrocarbon reservoirs based on the petro-elastic model. The method may be executed by a computer system.