earthquake epicenter 6 earthquake magnitude 6 Ambato 4 Andes 4 Argentina 4 Catamarca 4 Compressive deformation 4 Decollement levels 4 Earthquakes 4 Sierras Pampeanas 4 basement rock 4 compression 4 crustal structure 4 decollement 4 deformation 4 earthquake mechanism 4 focal mechanism 4 modeling 4 seismic moment 4 seismicity 4 seismotectonics 4 strain 4 strike-slip fault 4 waveform analysis 4 Arica 2 Arica and Parinacota 2 Chile 2 Major Chilean earthquakes 2 Nazca plate 2 South American plate 2