Geologic Points of Interest on the drive from Calgary to Field

As you begin your drive west from Calgary, you’ll see the terrain change from generally flat prairie to gently rolling hills. If you keep an eye out along the highway, you might notice some drumlins, teardrop-shaped hills caused by the motion of glaciers during the last Ice Age, when Alberta was completely covered by ice.

Drumlin at Morley

Drumlin at Morley

If you keep an eye on the left side of the road as the terrain becomes more hilly, you might be lucky enough to spot the first outcrop– loose shaley rock tilted down towards the east. This outcrop marks the beginning of the Foothills region, where rock is deformed by the force of the collisions between proto-North America and volcanic island arcs which formed the mountains between the Pacific coast and Alberta. In the Foothills rock layers dip down toward the west because they were formed as a result of buckling in the land as rock from the east was pushed forwards. In the mountains proper the rock layers dip down to the east because layers of rock from the east have been thrust above layers of rock to the west.

The first major mountain you’ll encounter as you travel into the mountains is Mount Yamnuska, which has Cambrian limestone (520 million years old) thrust over Cretaceous sandstones and shales (75 million years old). If you take a close look, you’ll notice the McConnell Thrust Fault, the boundary between the Cambrian and Cretaceous rock.

McConnell Thrust Fault on Mount Yamnuska

McConnell Thrust Fault on Mount Yamnuska

If you stop to stretch your legs in Canmore, you can visit the Hoodoos, tall structures formed from glacial till.

Hoodoos near Canmore

Hoodoos near Canmore

After you pass Canmore, you’ll notice several quarries. A particularly impressive example is found at Lac Des Arcs. If you look out across the lake to your right, you’ll see an industrial complex and a massive pile of whitish rock. At quarries like this, limestone is extracted and processed to be used as cement.

As you enter the town of Banff, you’ll notice an impressive anticline, a fold in the rock shaped like an arch.

As you continue through Banff, you may want to stop for a dip at the Banff Hot Springs, naturally heated water from Sulfur Mountain. The water’s temperature ranges between 37 and 40 degrees Celsius, and it contains minerals such as sulphates and bicarbonates derived from the water’s passage through the rock. The water from the hot springs percolated through Mount Rundle for hundreds of years, heated by the pressure of the rock, before emerging through the Sulfur Mountain Thrust Fault.

Water Movement

Water Movement

This is by no means an exhaustive list of the geologic points of interest you can find as you drive through the Canadian Rockies, so (as long as you’re not the one driving) pay lots of attention to the scenery as you drive! It may also be a good idea to invest in a guide book such as Ben Gadd’s Handbook of the Canadian Rockies, a large and comprehensive guide describing the natural history of the region, hikes and trails, and wildlife and plants. At $45 it’s an expensive guide, but well worth it. Another choice is Frommer’s British Columbia and the Canadian Rockies, which is priced lower at less than $17 but is more general and focusses more on recreation.

Pictures are from the Geologic Survey of Canada and Parks Canada. For a virtual tour of more geologic points of interest in Southern Alberta, visit the Geologic Survey of Canada.

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