An analysis of pressure stimulated currents (PSC), in marble samples under mechanical stress

The pressure stimulated current (PSC) technique was used in two variations, LSRT and SST for the investigation of the relations governing stress rate dS/dt, electric charge release and the behaviour of the damage parameter D, when a rock sample is driven to fracture by application of uniaxial compressional stress. It was verified that PSC originates from the change in the Young’s modulus rather than from the change in the stress rate. The total charge released during stress application up to fracture reaches almost the same values irrespectively of the stress rate, which is in full agreement with theory. It was also found that a proportionality exists between D and the scaling factor γ that correlates PSC peaks with the stress rate.