The scientific community started to focus its attention on this region, in particular because of the well-known enigma that concerns the generation of a plateau in the absence of a collision scheme. Hence, over the past decades, a series of seismological projects (e.g. Wigger, 1991; Wigger et al., 1994; Schmitz et al., 1997, ANCORP Working Group, 1999 and 2003; Graeber and Asch, 1999; CINCA Working Group, 1997; Bock et al., 1998; Haberland and Rietbrock, 1999; Schurr et al., 2006;) were undertaken to bring light on understanding the many interacting geologic-geodynamical processes in the Central Andes. These passive and active seismic experiments provided unique results that enabled, for the first time, the identification of deep structures in the crust as well as the depth and topography of the Moho- discontinuity (Beck et al., 1996, Zandt et al., 1996; Yuan et al, 2000). The Moho and implicitly the crust of the Andes mountain chain is a topic of study that has always been controversial.