| ca. 1,000 m (3,300 ft)|
Arica y Parinacota Region
| Zapahuira Formation, Huaylas Formation|Oxaya Formation Wikipedia
Oxaya Formation (Spanish: Formación Oxaya) is a geological formation in northern Chile made up of ignimbrite sheets. The formation formed about 25 to 19 million years ago in the Late Oligocene and Early Miocene.