Hell Creek Formation

Who doesn’t like dinosaur bones?

Although the name doesn’t necessarily incline one to visit, Hell Creek Formation is one of the most popular tourist destinations in Montana. In keeping with the state’s history as a naturalist’s dream, Hell Creek is a major exposure of prehistoric fossils and rocks.

Located near Jordan, Hell Creek lies in the badlands along the eastern portion of the state. The whole region itself spreads across a few different areas, including parts of North Dakota, South Dakota and Wyoming.

The Hell Creek Formation is actually more of a geological term than a place. It refers to the current geographical state of the region, as it has existed since the Cretaceous period. Hell Creek Formation actually lays on top of the Lennep Formation, the uppermost crust located in Montana itself.

Fun Fact : Visitors to “Pompey’s Pillar,” the site designated by famous explorer William Clark during the Lewis and Clark expedition, is located at the Pompey’s Pillar National Monument, an isolated section of the Hell Creek Formation.

So what is the Hell Creek Formation?

The Formation itself is comprised of freshwater clay, mudstone and sandstone deposits, left during the last part of the Cretaceous, the Maastrichtian period. Fluctuating river activity during this time caused various deltas and swamp areas to develop, crafting the land as it stands today.

What about the dinosaurs?

Currently, Hell Creek Formation is one of the premier excavation sites for the introduction of dinosaur fossils into the commercial market. The area is known for its dinosaur teeth and fragments of an ancient reptile called the crocodylian osteoderm.

Other notable fossils include the lasting presence of various invertebrates (prehistoric animals with no spinal column), plants, mammals, fish, reptiles and amphibians.

Fun Fact : Despite its existence as a freshwater habitat, shark and ray teeth have been found in the area around Hell Creek Formation, suggesting that these ocean creatures could once survive without saltwater.

Some notable dinosaur bones found in the Hell Creek Formation area include:

And yes, even evidence of the feared Tyrannosaurus Rex has been found in and around Hell Creek!