Experimental investigations of density and velocity characteristics of gneises at high pressures and temperatures

Elastic-density characteristics of gneises with a depth change on nonlinear laws. The experiments show that the VP=f(H) and p=f(H) dependences have complicated regularities: on the curves velocity and density inversion zones with maxima and minima manifestation are marked. It was shown that rocks differentiation on elastic-density parameters in probed varieties of gneises in laboratory conditions at the atmospheric pressure and room temperature and at the simultaneous influence on samples of deep PT parameters depends on the percentage content of high-density pyroxene and amphibole, and also stratified biotite. These materials enabled to complement and correct before the known information about “velocity-density” dependence on different depths, widely use at a seismic-gravity modelling.