The geochemistry of pillow basalts from the Chonos Metamorphic Complex (CMC) and the Eastern Andes Metamorphic Complex of Aysen (EAMC) indicates contrasting tectonic environments for these basic lavas. They have E-MORB and continental alkaline affinities, respectively. The MORB-like basalts are metamorphosed in the pumpellyite-actinolite metamorphic facies, with mineral associations indicative of relatively high P/T metamorphism. The continental alkali basalts exhibit pumpellyite-chlorite assemblages developed in a low to intermediate P/T regime. These contrasting eruptive and metamorphic settings agree with recently established age differences between the complexes, and invalidate direct correlation between them.
Áreas temáticas de ASJC Scopus
- Procesos de la superficie terrestre