The Mudstones – in spanish ‘lodolitas or fangolitas’, so called in Ibero and Suramérica – are natural materials conformed up of the subclasses silt and clay, or their combinations, which usually also include the sand grain size, fine to very fine; are overconsolidated rocks, from an geotechnical point of view. These sediments can be evaluated both by classical methods and instrumental analysis techniques, revealing unknown and important variables in the genesis of wide and acute processes that compromise the Crust, object of study of modern geodynamics exogenous. While it is true that the problems in clay shales (mudstones) date back many years, it was only from the early 1960’s that they were extensively studied [1].