Fossils

Fossils like this turtle and fish provide information about past environments.
Fossil fish with turtle.

Photo by Cliff Miles

The fossil record preserved within the Eocene Green River Formation of Fossil Basin is world-renowned. Discoveries of new fossil species from the ancient lake sediments continue to expand understanding of the paleoecosystem.

The quality of fossil preservation is extraordinary, nearly unparalleled in the fossil record. The quiet-water, fine-grained lake sediments, and water conditions that excluded scavengers combined to preserve articulated skeletons (all bones are in place rather than scattered). Delicate fossils, rarely preserved elsewhere, yield valuable scientific data.

Today less than 1% of Fossil Lake is protected and managed by the National Park Service. Fossil Butte National Monument is a site that promotes the protection of this world-class paleontological heritage.

Click on links below to learn more about fossil species from the Fossil Butte Member (FBM).
 
fish with forked tail and deep belly
D. dentatus FOBU791 specimen

NPS Photo

Fossil Fish Species

27 fish species have been identified from the Fossil Butte Member (FBM).
 
flattened bat skeleton with long tail and claws on each digit
O. finneyi cast of private specimen

NPS Photo

Fossil Mammal Species

10 mammal species have been identified from the Fossil Butte Member (FBM).
 
flattened snake skeleton curled up
B idelmani cast of private specimen

NPS Photo

Fossil Reptile Species

The 15 species of reptiles identified from the Fossil Butte Member (FBM) include turltes, lizards, crocodilians, and snakes.
 
flattened frog with long hind legs
A. paulus cast of private specimen

NPS Photo

Fossil Amphibian Species

2 amphibian species have been identified from the Fossil Butte Member (FBM).
 
flattened dragonfly with 4 long wings with markings
Dragonfly FOBU448 specimen

NPS Photo

Fossil Arthropod Species

Several arthropod specimens have been identified from the Fossil Butte Member (FBM).
 
flattened palm frond with long stem
Palmites FOBU446 specimen

NPS Photo

Fossil Plant Species

Several plant specimens have been identified from the Fossil Butte Member (FBM).
 
flattened bird skeleton with bent long legs and disarticulated wings
P. cercanaxius cast of private specimen

NPS Photo

Fossil Bird Species

Over 30 species of birds have been identifiefd from the Fossil Butte Member (FBM).
 

For raw data from the Fossil Butte Research Quarry, click here.

Last updated: December 11, 2020

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Kemmerer, WY 83101

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