Fish Fossils

Fossil fish occur within the beds of what was once the ancient lake Uinta, now part of the Green River Shale formation of western Wyoming. Sometime during the Eocene Epoch of geologic time (50,000,000 years ago) volcanic or climatic changes probably occurred which disrupted the lake’s ecology and resulted in massive fish mortality. When quarried today, the shale reveals impressions and actual bones of several species.