“…Paleocene to Eocene sections at the Pacific offshore region and Central Valley area are controlled by normal faults (Becerra et al, 2013), while to the east over the axial Andes and retroarc region arc-related rocks are present (Suárez and Emparán, 1997) with an unknown mechanics of formation. These offshore Paleogene depocenters were inverted by latest Eocene times (Becerra et al, 2013), while at the retroarc region a contractional pulse of deformation has been related to the Chos Malal fold and thrust belt (Cobbold and Rossello, 2003). Oligocene to Miocene extensional processes affected the Present arc and A c c e p t e d M a n u s c r i p t retroarc regions with no basin record at the forerac zone.…”