Spence Shale

Spence Shale
Stratigraphic range: Cambrian, Miaolingian, Wuliuan
~
Hyolitha, Spence Shale
TypeMember
Thickness9–120 m (30–394 ft)
Lithology
Primarycarbonate mudstones
Othercarbonate-rich siliciclastic mudstones and Wackestones
Location
RegionIdaho, Utah
CountryUnited States
Type section
Named forSpence Gulch
Named byCharles Doolittle Walcott

The Spence Shale is the middle member of the Langston Formation in southeastern Idaho and northeastern Utah. It is exposed in the Bear River Range, the Wasatch Range and the Wellsville Mountains. It is known for its abundant Cambrian trilobites and the preservation of Burgess Shale-type fossils.

The type locality is Spence Gulch in southeastern Idaho, near the town of Liberty. It was first described by Charles Doolittle Walcott in 1908.