Fossil Butte National Monument
During the Eocene Epoch (56 to 34 million years ago) part of what is now south west Wyoming north east Utah and north west Colorado was a sub-tropical lake ecosystem. For around two million years this part of Wyoming was at the bottom of a large lake. The remains of plants and animals that lived in the lake were preserved in the sediment at the bottom of the lake and became fossilised so the ancient lake is known as Fossil Lake. The lake has long gone and this part of Wyoming is now cool sagebrush desert. In the 19th century coal was mined in the area and the miners found plenty of fossils which they sold to collectors. On October 23, 1972 Fossil Butte National Monument was created on 3,318 hectares (8,200 acres) in order to preserve a small part a of the former lake bed.
Cast of Caiman Fossil
The ancient lake was home to crocodilians. This picture shows a cast of a T. greenriverenis Caiman. Other reptile fossils on display include snakes and turtles. Click Tab 2 to see a cast of soft shell turtle fossil. This picture has been edited to reduce reflections from the glass case.
Cast of Lizard Fossil
On display in the Visitor Center is a cast of a Monitor Lizard (S. ensidens) fossil, the largest lizard species found in the National Monument This specimen measures 1.86 metres (6 feet). Like living monitor lizards, Its long neck, powerful limbs and claws for climbing are very like those of a living Monitor Lizard. The exceptionally long tail would have been used both for balance and for defence.
Visitor Center
While the creation of Fossil Butte National Monument has protected the fossils within its boundaries, outside the National Monument there are numerous quarries where commercial fossil hunting continues to to discover fossil specimens which are sold to museums and private collectors. Inside the National Monument the scenery is pleasant rather than spectacular and there is no much else to see outdoors. There is a scenic drive through the National Monument but it is mainly unsurfaced (unpaved) and rough in places. The Visitor Center is the place to go to find out about the fossils found here. Click Tab 2 to see a view across Fossil Butte National Monument from Chicken Creek Road Scenic Drive
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