Drumheller: A Rocky Dinosaur Story

One of the largest collections of dinosaur bones in the world is continuously being found in Drumheller, AB, Canada. After being dug out of the ground, cleaned, preserved and examined the fossils are scattered around the globe for millions to see.

When I visited the Australian Museum in Sydney I frolicked through the dinosaur skeletons and soon realized almost the entirety of their collection was from Alberta. With over 130 000 fossils in their collection, Drumheller and Dinosaur Valley is a one stop shop for fossils.

It wasn’t until recently that I was able to actually visit Drumheller, on a frigid dry winter morning, I got up before the sun and drove through the sprawling prairies in order to explore this wonderment for the day.

The Royal Tyrell Museum gets hundreds of thousands of visitors per day. You can walk through the badlands and see the rock formations and hills that preserved the dinosaur fossils for millions of years.

The Ideal Day:

To experience Drumheller in a Day, you need to make a stop at the Royal Tyrell Museum where you will wander through the entire history of time. Then you can drive through the rolling hills of the badlands and take a walk through the Hoodoos. Definitely stop for a leisurely stroll through old downtown Drumheller, and maybe catch a photo with the worlds largest dinosaur (don’t worry he doesn’t bite).

Let’s Go Back in Time:

To talk about Dinosaurs, we should go back, way back, about 253 Million years ago to the beginning of the Mesozoic Era and the Lower Triassic. This is when the age of the dinosaurs began. However, in Drumheller the real history begins at 75 Millions years go near the end of their reign and the end of the Cenozoic.

(If I’m confusing you about geologic history jump here for a handy guide! It’s a hard topic to get your head around, when you think about millions of years!)

At this time Alberta was considered a low lying coastal plain. As the Rocky Mountains formed to the West and the continent grew on the East this area was intermittently covered and uncovered by rising oceans. The climate was sub-tropical, think Florida. These conditions meant the ability for perfect preservation.

Fossilization in simplest terms means the preservation of animal bones by having them slowly replaced by minerals. When you have warm wet conditions it allows for animals to die near the water and sink into the mud or silt. This allows their tissues to be dissolved quickly and the bones sheltered from the elements and encased. The mud and silt turns into a sedimentary rock as pressure around it causes it to dry and compress. As the bones lay in this rock, the bone matter is replaced by harder minerals that allow them to survive for millions of years this is a fossilization process known as permineralization.

 

Now for the Rocks:

Drumheller is in south east side of Alberta and lies a few hundred kilometers from the Rockies. It is easiest to access from Calgary, but I made the drive from Edmonton.

Three geologic formations explain the fossil record here, the Oldman formation, Dinosaur Park formation and Horseshoe Canyon formation. Similarly, all three of these formations are described as sandstone, siltstone or quartzite with interlaying layers of mudstone. Now you can ask my how can you get layers of different things throughout a geologic formation?

A geologic formation is described as a unit of stratigraphy, which is layers of rock laid down on top of each other that have similar properties and occurred during a similar time period. These are useful for dating fossils as you can often find the same formations across a large area. Let’s think for a minute though, you might be imagining these formations as kilometer thick. There you’d be wrong, some of these formations may be at most a few meters thick and that’s including all the various stratigraphic layers within them. Some may be barely there.

To give fossils an age there are typically two methods used, relative dating which uses the stratigraphy I just mentioned to place layers of rock on top of one another and determine the age based on fossils which have been dated absolutely. Absolute dating is done through a machine and measures half lives of the material in the rock, such as carbon dating.

Geologic Record:

Imagine you’re in the late Cretaceous (about 80 Million Years ago (Ma)), Tyrannosaurus is the dominant predator that you are looking out for. Some mammals are starting to appear and marine life is flourishing.

Oldman:

If you’re in what is now Dinosaur Valley then you are in a fluvial environment, practically paradise, where there is lots of water running through and many river systems. The area is thriving with plant and animal life and it stays this way for a million years, from 77.5Ma- 76.5 Ma. Now this formation is 40 m thick in some places.

Dinosaur Park:

As time keeps going, the landscape starts to change. Rivers are flowing from the mountains into Dinosaur Valley and leaving thin sediment through the area. Rivers are still widespread. You still have tropical temperatures. There is a variety of dinosaur species roaming the area from Ornithopods to Ceratopsians to Ankylosaurs. Life goes on from 76.5Ma- 74.8Ma. Now this formation is 70m thick and a UNESCO world heritage site for the amount of fossils found.

Above Dino Park:

The Bearpaw formation overlies Dino park, it is full of Ammonites. It is shale. This means it was a marine environment, think ocean. Imagine if you will a tropical perfect environment completed covered by the Bearpaw Sea. Dinosaurs are still found in this formation but rarely.

Then there is the Horseshoe Canyon formation, spanning 7 Million years and up to 230m thick in some areas. This formation is full of coal seams and mudstone. If you lived in this time the landscape of Alberta would be full of estuaries, floodplains and swamps. It is also colder than during the millions of years before. Albertosaurus and Edmontosaurus are roaming freely, enjoying their environment.

The End of an Era:

We all know what happens next. The dinosaurs go extinct; the planet is hit by a meteor 15 km wide. The earth goes dark and cold, until it rebuilds.

The Landscape Now:

You drive into Drumheller now and you don’t see the flat landscape you might expect from this story. Instead you see what looks like rolling hills, crevices showing the layers of sedimentary rock that was deposited millions and millions of years ago.

This is because up until almost 12 000 years ago there was mass glaciation throughout North America and the World during the quaternary. These glaciers and some rivers carved through the soft rocks and created the landscape we see today.

So as you drive through the long and windy roads you can clearly see the layers of sediment and definitely worth a stop along one of the roadside turnouts to admire the layers of rock, and maybe even spot a fossil.

The Hoodoos:

The Hoodoos trail is one of the best walks to do while out exploring Drumheller. Hoodoo was a form of Aboriginal magic through North America, don’t confuse it with Voodoo! The Hoodoo’s are harder rock placed on the top of softer sandstone. Over time the elements erode down and the hard rock protects the pillar from eroding down. This causes large cones.

Drumheller is fascinating and awe inspiring. The ability to glimpse back in time millions of years can’t be beat anywhere.