The Story of Pipestone Creek

During the Late Cretaceous, what is now the Peace Region was a low-lying flood plain. Rivers carried huge amounts of sediment from the mountains in the West toward the Bearpaw Sea in the East. Although there were no grasses at this time yet, the flood plain was covered with lush vegetation that plant-eating dinosaurs were feeding on.

It must have been an extremely wet year, and all the rivers were in flood. Turbulent waters were overflowing the banks. The pachyrhinosaur herd was following their usual migration route when they reached a spot they had to cross the river. Normally it would have been an easy crossing: some wading in the muddy waters, some swimming. Even the old and the babies could make it without much trouble.

This time it was different. The leading animal cautiously stepped into the water, and with great difficulty managed to reach the other shore. Since the water level was so high, it was hard to gain a foothold on the muddy shore on the other side. The herd followed him. They were good swimmers, but not in a flooding river. Some were not able to stay afloat, were pulled down and swept away to their death. Those that reached the other bank had trouble climbing up to dry ground. As they trashed and struggled, the ground became more and more muddy and slippery to the point where it became impossible to gain a foothold. Yet, the animals kept coming. Sensing their immediate death, they panicked, and hundreds of animals drowned.

The flooding river carried their carcasses downstream, together with other debris, until they were thrown or stuck on the banks, maybe at a sharper bend of the watercourse. There they laid, the bodies decomposing. Meat eaters soon found this bounty, and they came to feast. As they tore into the flesh, their teeth left marks on the bones, and some of their loose teeth were shed.

The carcasses lay on the banks for years. Scavengers and subsequent smaller floods mixed and rearranged the bones without carrying much away. The next major flood buried this gruesome scene with a fresh layer of mud which prevented further decay and scattering of the bones. Subsequent floods buried the bone layer deeper and deeper. Due to the increasing pressure, even the fine pores of the bones were filled with fine sediment.

As geologic time passed by, mineral bearing ground water turned the bone material to stone. Pressure somewhat deformed these mineralized, fossil bones.

Some seventy two million years later, the area was emerging from under the ice cover as the glaciers melted. The landscape was much different. A completely new type of vegetation and animal life returned to the barren land. New rivers and creeks were cutting into the sediments the ice left behind. One such creek happened to cut a small valley intersecting the bone layer. It is called Pipestone Creek.

Katilin Ormay, Paleontological Society of the Peace (PSP)