Alsea Formation

The Alsea Formation is a geologic formation in Oregon. It preserves fossils dating back to the Rupelian stage of the Oligocene period.

Fossil content
The following fossils have been reported from the formation:

Mammals

 * Aetiocetus cotylalveus
 * Maiabalaena nesbittae
 * Simocetus rayi

Fish

 * Orthechinorhinus davidae