A 75-million-year-old floodplain
The stark, sculpted terrain of Dinosaur Provincial Park is a relatively recent feature. Around 13,000 years ago, meltwater from receding glaciers carved through soft sedimentary rock, creating the badlands we see today. This ongoing erosion, occurring at a rate of up to four millimeters per year, continually exposes the rock layers of the Dinosaur Park Formation. These layers of sandstone, mudstone, and siltstone were originally deposited between 77 and 75 million years ago during the Late Cretaceous Period.
At that time, this area was a low-lying coastal plain bordering the western edge of the Bearpaw Sea, an immense inland sea that split North America. The climate was subtropical, and the environment consisted of swampy river deltas and lush forests of giant redwoods, palms, sycamores, and magnolias. Rivers flowing from mountains to the west deposited the sediments that would eventually entomb a vast array of life. This specific set of conditions was perfect for preserving the bones of dinosaurs and other animals, creating one of the most concentrated fossil deposits in the world.
A world-class fossil deposit
Dinosaur Provincial Park has yielded an unmatched diversity of fossils from the Late Cretaceous. More than 500 species of organisms, from microscopic fern spores to giant dinosaurs, have been identified here. The park contains its dinosaurs, with fossils representing more than 50 distinct species discovered. Over 150 complete or near-complete dinosaur skeletons have been unearthed since excavations began in the late 1800s.
The fossil beds contain remains from every known group of Cretaceous dinosaurs. Herbivores are abundant, including horned dinosaurs like Centrosaurus and Styracosaurus, and a wide variety of duck-billed hadrosaurs. Armored ankylosaurs and dome-headed pachycephalosaurs also roamed these ancient floodplains. The primary predator of this ecosystem was the tyrannosaurid Gorgosaurus, a smaller relative of Tyrannosaurus rex. The fossil record is not limited to dinosaurs; it includes a complete paleo-ecosystem. Remains of fish like sharks and rays, amphibians, turtles, lizards, and crocodile-like champsosaurs are common. The fossils are so plentiful that large deposits of jumbled bones, called bone beds, have been found, some containing the remains of hundreds of individual animals.