On the role of thermodynamic conditions in rocks and minerals stability

This paper presents a new thermodynamic method for analyzing and determining the stability conditions of various rocks and minerals. The new method proves that, in most cases, the actual pressure applied to rock or minerals is different from the lithostatic pressure that is very important for estimating the depth of both rock and mineral formation. It also shows that the stability conditions for any rock or mineral depend on the deviations of the pressure and(or) temperature from their normal conditions, which are different for different rocks and minerals. The essential parameters for rock and mineral stability analysis are their volume thermal expansion α and compressibility β, the ratio P/T and the slope dP/dT. Thorough research of these parameters indicates a presence or absence of external (tectonic) forces during mineral or rock formation.