Hell Creek Formation

dinosaurs · fossils · geology · Montana

Ancient rock layers. The Hell Creek Formation is a division of rocks mostly from the Upper Cretaceous period, which was the very end of the age of dinosaurs. Scientists study these rocks to understand what the world was like back then.

Spans four states. This formation stretches across Montana, North Dakota, South Dakota, and Wyoming, covering a huge area of the northern United States. Hell Creek near Jordan, Montana, is where scientists first discovered and studied these rocks.

Packed with fossils. The Hell Creek Formation is intensively studied because it contains amazing fossils of ancient creatures and plants. These fossils help scientists understand what lived during the last days of the dinosaur era.

Protected landmark. In 1966, the Hell Creek Fossil Area was officially designated as a National Natural Landmark by the National Park Service, recognizing how important it is for science. A small piece of it is even protected at Pompeys Pillar National Monument.

Windows to the past. By studying the rocks and fossils in the Hell Creek Formation, scientists have discovered what happened when dinosaurs disappeared from Earth about 66 million years ago.