La Portada Formation (Spanish: Formación La Portada) is a geologic formation of Miocene and Pliocene age located near the Coast Range of northern Chile. The coarse-grained sandstones of the formation contain penguin fossils.[1][2]
| La Portada Formation | |
|---|---|
| Stratigraphic range: Miocene–Pliocene | |
 View of La Portada, the namesake arch made of La Portada Formation rocks resting on darker rocks of Jurassic La Negra Formation | |
| Type | Geological formation |
| Sub-units | Cerro Bandurrias & Cuesta del Burro Members |
| Underlies | Mejillones Formation |
| Overlies | Caleta Herradura Formation |
| Lithology | |
| Primary | Sandstone |
| Location | |
| Coordinates | 23°24′S 70°30′W / 23.4°S 70.5°W |
| Approximate paleocoordinates | 23°36′S 69°30′W / 23.6°S 69.5°W |
| Region | Antofagasta Region |
| Country |  Chile |
| Type section | |
| Named for | La Portada de Antofagasta |
  La Portada Formation (Chile) | |
See also
editReferences
edit- ^ Mejillones Peninsula at Fossilworks.org
- ^ Chávez, Martín F. (2008). "Los pingüinos fósiles de Sudamérica". Libro de Actas. I Simposio - Paleontología Chile - 2008 (in Spanish). pp. 116–120.
Further reading
edit- L. Ragaini, C. di Celma, and G. Cantalamessa. 2008. Warm-water mollusc assemblages from northern Chile (Mejillones Peninsula): new evidence for permanent El Nino-like conditions during Pliocene warmth?. Journal of the Geological Society 165:1075-1084