f The Variation of Electric Properties of Minerals and Rocks at High Pressure and High Temperature

The investigation of the physico-chemical activities of minerals and rocks is important both for seismology and for magnetotelluric surveys. This paper presents the variation of electric properties of geological samples under the most spread process of metamorphism-dehydrogenation. The investigation has been caried out with high pressure and temperature at isothermal (T = const.) and isobaric (p = const.) conditions on quasihydrostatic pressure devices. Characteristic properties of the variation of electric resistivity were obtained in many minerals and some rocks.