Clearwater Formation, Shale formation in Cold Lake, Alberta, Canada.

The Clearwater Formation is a stratigraphic unit of Early Cretaceous (Albian) age in the Western Canada Sedimentary Basin of northeastern Alberta. It consists mainly of black and green shale with interbedded grey and green sandstone and siltstone, and ironstone concretions. It reaches a maximum thickness of 85 metres on the Athabasca River, thins to 6 metres in the Cold Lake area, and wedges out towards the south.

The layer was named in 1893 by geologist R.G. McConnell after the Clearwater River near Fort McMurray. This early study helped scientists understand the region's underground rock structure.

Fossils from the Clearwater Formation are held at the Royal Tyrrell Museum of Palaeontology in Drumheller. The nodosaurid Borealopelta markmitchelli, a well-preserved holotype, was recovered at the Suncor Millennium Mine. Plesiosaurs such as Nichollssaura and ichthyosaurs such as Athabascasaurus came from Syncrude Canada Ltd.'s mines near Fort McMurray.

The Clearwater Formation lies mostly in the subsurface of northeastern and central Alberta; it is exposed only on the lower Athabasca River and along the Christina River, a tributary of the Clearwater southeast of Fort McMurray. It reaches 85 metres thick on the Athabasca River, thins to 6 metres near Cold Lake and wedges out southward, absent south of Edmonton.

The nodosaurid Borealopelta markmitchelli, an armoured dinosaur, was found at the Suncor Millennium Mine in Clearwater strata, about 200 km from the nearest known palaeo-shoreline. Its bloated carcass likely floated for days before sinking. All Clearwater specimens, including Nichollssaura and Athabascasaurus, are held at the Royal Tyrrell Museum of Palaeontology.