Trabajo presentado en el VII Simposio Peruano de Geoingeniería.Por: G. Zúñiga, Skava Consulting, Santiago, Chile.AbstractOne of the main challenges facing engineering geology is the generation of models of major structural discontinuities that are useful for rock engineers to assign mechanical properties to these discrete bodies in open-pit deposits for the estimation/quantification of the likely physical behavior of these and the rock masses at the engineering scale. This paper presents a brief description of the application of the Geological-Engineering Classification of Fault Rocks of Fasching & Vanek (2011) for use as a geotechnical characterization tool to contribute in decreasing the epistemic uncertainty associated with these discontinuities.