Discover Canada and Explore the Fossils and Geodiversity of Fort McMurray in Alberta
- Wayne Munday
- Oct 15
- 4 min read
Sip back and discover Canada and explore the fossils and geodiversity of Fort McMurray situated on the Athabasca River in north east Alberta and serves as the gateway to the Athabasca Oil Sands one of the world’s largest bitumen deposits. Beneath its industrial landscape lies a remarkable Early Cretaceous record preserved in the Wabiskaw–McMurray succession that tells a story of a vast ancient area of rivers, estuaries and a shallow sea shaped by sediment washed down from the Canadian Shield, Appalachian–Grenville belt and Cordilleran mountan building event. Over millions of years, kerogen-rich organic matter was deposited underwent burial and thermal maturation, producing the region’s heavy, viscous bitumen trapped in porous sands of the McMurray Formation. The formation also preserves a fossil record of ichnofossils such as Skolithos, Teichichnus, and Thalassinoides, alongside rare macrofossils. Notable vertebrate discoveries include the nodosaur Borealopelta markmitchelli as well as marine reptiles including Nichollssaura borealis, Wapuskanectes betsynichollsae and Athabascasaurus bitumineus showing the diversity of Early Cretaceous terrestrial and marine ecosystems in northern Alberta.
Fort McMurray is located in north east Alberta by the Athabasca River approximately 435 Km kilometres from the provincial capital of Edmonton. Fort McMurray serves as the gateway to the Athabasca Oil Sands one of the world’s largest bitumen deposits. Visitors can reach Fort McMurray via Highway 63, locally known as the “Northeast Alberta Trade Corridor” or through Fort McMurray International Airport (YMM) which offers regular connections to Edmonton, Calgary and beyond. Despite its industrial reputation the region has a surprising natural beauty of dense spruce forests and winding waterways. Fort McMurray is where the Canadian Shield and the Western Canadian Sedimentary Basin meet and has been shaped over millennia by glaciation.
Beneath the operations of Alberta’s oil industry lies an older story written in sand, silt and bone. The Athabasca Oil Sands is one of the world’s largest hydrocarbon reserves and is made up of the Wabiskaw–McMurray succession that also preserves an Early Cretaceous landscape of rivers, estuaries and shallow seas that shifted repeatedly as sea levels rose and fell back leaving behind ubiquitous trace fossils the occasional dinosaur and marine reptile.
The Wabiskaw–McMurray succession dates to the Early Cretaceous and tells a story of the gradual transformation of a vast river-dominated landscape into a shallow marine environment shaped by tectonic uplift, sediment supply from the Canadian Shield, the Appalachian–Grenville belt of eastern North America, the Cordilleran orogen to the west and rising sea levels.
The story begins with the McMurray Formation laid down for 7 million years between the Late Barremian – Aptian Stage into an network of rivers and tidal estuaries that flowed northward across a low-lying plain along the edge of the Western Interior Basin. These channels and floodplains laid down alternating layers of sandstone and mudstone and in the meandering bends where the river and tidal currents slowed down or met the sea both point bars and channel sands formed. These in combination with abandoned channel belts and bay fills not only acted as natural traps for the Athabasca bitumen but also the rapid burial of animals.
The Athabasca bitumen formed over millions of years through a combination of organic deposition of kerogen rich organic matter, its burial and the influence of thermal maturation. Over time, the sand, silt and clay derived from surrounding regions such as the Canadian Shield, Appalachian, and Cordilleran orogens were deposited and increasing burial increased pressure and temperature to initiate diagenesis and the transformation of kerogen into a heavy viscous bitumen rather than oil.
The regional fossil record is dominated by ichnofossils or trace fossils created by the activity of invertebrate organisms living in estuarine and brackish conditions rather than from he presence of abundant bonebeds. Trace fossils, including burrows and feeding structures, record the activity of invertebrates from both tidal and river environments with common ichnogenera such as Skolithos, Teichichnus, Thalassinoides, Planolites and Siphonichnus.
Among fossil discoveries of vertebrates in the region has been a nodosaurid ankylosaur called Borealopelta markmitchelli (meaning 'northern shield') dated to about 110 million years ago. This was a plant-eating, armored dinosaur, weighed nearly 1,400 Kg, shows an extraordinary level of preservation presumably as the result of its body being washed out or possibly floating out to sea where it sank and was rapidly buried allowing such delicate features to be conserved. Discovered by accident in 2011 in an oil-sands mine north of Fort McMurray Borealopelta is now displayed at the Royal Tyrrell Museum.
Interestingly, analysis of this fossil has suggested that Borealopelta may have exhibited "countershading" by having a red-brown pigment on its back and a lighter belly this possibly acted as camouflage against predators. Although this interpretation is debated among experts due to uncertainties about fossilised pigments and chemical alterations.
The Early Cretaceous Wabiskaw Member of the Clearwater Formation has also yielded some of North America’s most remarkable and oldest marine reptile fossils that lived in the Western Interior Seaway over 100 million years ago. Among these discoveries, Nichollssaura borealis, a small short neck leptocleidid plesiosaur found in 1994 at the Syncrude Canada Base Mine and is one of the oldest and most complete Cretaceous plesiosaurs in North America.
In 1998 and 2000 other significant fossils were recovered from the same oilsands region including Wapuskanectes betsynichollsae the continent’s oldest known elasmosaurid and Athabascasaurus bitumineus a medium-sized ichthyosaur. These specimens were preserved in siliciclastic sediments of the Wabiskaw Member and have helped to shed light on the diversity and evolutionary history of long-necked and predatory marine reptiles during the Early Cretaceous.
Public stewardship of these finds is governed by provincial law. Alberta’s Historical Resources Act protects fossils, and while surface collection of loose specimens outside protected areas is sometimes permitted, excavation without a permit is illegal. Reporting discoveries, documenting GPS locations, and contacting institutions such as the Royal Tyrrell Museum is the responsible way to report fossil finds.
