La Portada Formation () 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.Mejillones Peninsula at Fossilworks.org
See also Cerro Ballena Coquimbo Formation Navidad Formation
References
Further reading 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