Abstract The Aysén-Río Mayo Basin was a back-arc/marginal basin developed in southwestern South America (43°–47°S) between the Tithonian–Aptian. Its sedimentary fill corresponds to Coyhaique Group, which represents transgressive–regressive succession. Six lithofacies and five microfacies were defined for three outcrops exposed south of (45°40’S). have mixed calcareous–volcaniclastic composition...
