The Dinosaur Park Formation is the uppermost member of the Belly River Group (also known as the Judith River Group), a major geologic unit in southern Alberta. It was laid down during the Campanian stage of the Late Cretaceous epoch between 76.6 and 74.8 million years ago. It was deposited in alluvial and coastal plain environments, and it is bounded by the nonmarine Oldman Formation below it and the marine Bearpaw Formation above it.