Tensleep Sandstone

The Tensleep Sandstone is a geological formation of Pennsylvanian to very early Permian age in Wyoming.[2]

Tensleep Formation Stratigraphic range: Late Pennsylvanian-very Early Permian ~308–298 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Underlies	Phosphoria & Chugwater Formations
Overlies	Sacajewea & Amsden Formations
Thickness	up to 535 feet (160 m)
Lithology
Primary	Sandstone
Other	Limestone
Location
Coordinates	42.6°N 108.2°W
Approximate paleocoordinates	4.3°N 35.2°W
Region	Wyoming
Country	USA
Type section
Named for	Ten Sleep, Wyoming
Named by	N.H. Darton[1]
Year defined	1904
Tensleep Sandstone (the United States) Tensleep Sandstone (Wyoming)

Trace fossils

Hylonomus

In 1932 Edward Branson and Maurice Mehl reported the discovery of a fossil trackway in the formation.[3] A new ichnospecies, Steganoposaurus belli, was erected for these footprints.[3] The tracks were probably made by a web-footed animal slightly less than three feet long.[3] This creature was originally presumed to be an amphibian, but the toe prints it left behind were pointed like a reptile's rather than round like an amphibians. The actual trackmaker may have been similar to the genus Hylonomus.[4] The ichnogenus Tridentichnus are similar footprints preserved in the Supai Formation of Arizona.[5]

References

1. Darton, N.H., 1904, Comparison of the stratigraphy of the Black Hills, Bighorn Mountains, and Rocky Mountain Front Range: Geological Society of America Bulletin, v. 15, p. 379-448
2. U.S. Geological Survey. "Geologic Unit: Tensleep". Retrieved 2014-12-23.
3. "Western Traces in the 'Age of Amphibians'," Lockley and Hunt (1995); page 34.
4. "Western Traces in the 'Age of Amphibians'," Lockley and Hunt (1995); page 35.
5. "Western Traces in the 'Age of Amphibians'," Lockley and Hunt (1995); pages 34-35.

Bibliography

• Lockley, Martin and Hunt, Adrian. Dinosaur Tracks of Western North America. Columbia University Press. 1999.