Abstract
Petrophysics referred to the intact rock or “rock matrix” studies its physical properties interpreting them in terms of its rock-forming components and characteristics (voids –pores and fissures–, grain interlocking, anisotropies, minerals, chemical composition, etc.). This interpretation has required: new microscopies for imaging the rock-forming components, new petrographic parameters and specific procedures for their quantification. The basic principles of Petrophysics referred to the intact rock and the main physical properties of interest in Applied Geology, Engineering Geology, Rock Engineering, etc. are summarized.
