Fossil Butte National Monument
| Fossil Butte National Monument | |||
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| Location: | Wyoming , United States | ||
| Specialty: | Fossil deposit, with predominantly aquatic life | ||
| Next city: | Kemmerer | ||
| Surface: | 33.2 km² | ||
| Founding: | October 23, 1972 | ||
| Visitors: | 16,552 (2011) | ||
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Fossil Butte National Monument is a protected area by the type of National Monuments in the southwest of the US -Bundesstaates Wyoming . It preserves a fossil deposit , the Fossil Lake with the deposits of the Green River Formation , including the very rich fossil Butte Member , from the Eocene about 50 million years ago.
The reserve was established in 1972 after the deposit was explored from the 1870s and finds were commercially marketed for several decades. It is administered by the National Park Service .
description
The reserve is located in Lincoln County , about 25 km west of Kemmerer . In the Eocene, about 50 million years ago, this was one of the three great lake landscapes that were found in the western United States from this period. The climatic conditions at that time are reminiscent of today's subtropical Florida .
The fossil finds consist almost exclusively of aquatic life forms, largely fish (e.g. Notogoneus osculus ), as well as crocodiles , softshell turtles , two types of bats , some dragonflies and other species. The finds are embedded in the Green River Formation, sedimentary rock of the great lake landscapes, which consists of sandstone and siltstone with embedded coal and oil shale . The particularly interesting layers are embedded limestone and dolomite , which are found here in such a fine composition that they have preserved not only bone structures, but also soft parts of the fossil fauna. The best preserved finds are in the so-called 18-inch layer , a limestone layer .
When the transcontinental railroad was built in the Rocky Mountains , settlement in the west also reached the region, which was previously only crossed sporadically by settlers' treks. In the 1870s, the near-surface hard coal was developed to supply the railroad. The miners made the first fossil finds. Between around 1900 and 1937 the fossil sites were used commercially and the fossils were sold to museums and private collectors around the world.
Web links
- National Park Service: Fossil Butte National Monument (official site; English)