Estilos eruptivos de basaltos cenozoicos del oeste de Santa Cruz extraandina, Argentina

GONZÁLEZ GUILLOT, M.; PONCE, J.F.

Congreso; XX Congreso Geológico Argentino; 2017

Eruptive styles of Cenozoicbasalts of western extra-Andean Santa Cruz, Argentina. Characteristics of Pliocenebasaltic flows and volcanoes in Patagonia are presented. The basalts wereerupted during the post-plateau stage in a slab window model. While most of thepost-plateau emissions occurred through scoria or spatter cones, along thewestern flank of the mesetas the effusions appear to have occurred through lavashields of scutulum type. One representative example occurs on the mesetaDesocupada, north of Viedma lake, where the shield also shows evidences of activityafter the retreat of piedmont glaciers. This suggests the slab window modelshould be revisited for the western basalts and to consider, in addition, amechanism of lithospheric relaxation and isostatic rebound for the genesisand/or ascent of the magmas.