Sundance Formation

Sundance Formation Stratigraphic range: Upper Jurassic
Type	sedimentary
Underlies	Morrison Formation
Overlies	Chugwater Formation
Lithology
Primary	limestone
Other	shale, sandstone
Location
Region	Western North America
Country	United States

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The Sundance Formation is a western North American sequence of Upper Jurassic agemarine shales, sandy shales, and sandstones.

The Sundance Formation underlies the western North American Morrison Formation, the most fertile source of dinosaur fossils in the Americas, and is separated by a disconformity from the underlying Upper Triassic Chugwater Formation red beds.

The Sundance Formation is known for fossils of an extinct species of marine cephalopod, Belemnites densus.

Fossil dinosaur 'footprints' on an ancient ocean shoreline are preserved in the formation and protected at the Red Gulch Dinosaur Tracksite, located in the Bureau of Land Management Red Gulch/Alkali National Back Country Byway, near Shell in Big Horn County, Wyoming.

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