A method and apparatus are provided for determining and expressing the elastic moduli within a body of earthen material; the method and apparatus for processing the method follows the steps of: (a) establishing the location of the body; (b) determining the Young's Modulus E using the formula E=.rho.V.sub.p.sup.2; (c) determining the Shear Modulus .mu. using the formula .mu.=.rho.V.sub.s.sup.2; (d) determining a Bulk Modulus .kappa. using the formula .kappa.=.rho.V.sub.p.sup.2/3(1-2.gamma.) where .gamma. equals Poisson's Ratio; and (e) selecting one or more of the determined moduli and entering such selected moduli in a data processor adapted to convert such selected moduli into a visual expression as, for example, a map of the selected moduli for the purpose of oil, gas or coal exploration, or earthquake hazard mapping.