Friday, 14 August 2020


There is a small roadcut exposure of the Eager Formation on the Ktunaxa Nation lands. The Lower Cambrian Eager Formation outcrops at a few localities close to Fort Steele, many known since the early 1920s, and up near Mount Grainger near the highway. 

This particular outcrop is on First Nations land. We wanted to take photographs of the site and be respectful of who live on and own the land now. This is the Ktunaxa traditional territory and while their history does not intersect directly with the fauna who lived here half a billion years ago, their boundaries need to be respected.

We stopped for about 10 minutes to photograph the exposures. I hopped out to look at a few pieces and photograph this specimen. The Olenellus trilobite bits & pieces were moults & remains that had a slight deformation or warping — perhaps laid down in a seabed with high action, active turbidity.

Olenellus are a genus of trilobites — extinct arthropods  — common in but restricted to Early Cambrian rocks some 542 million to 521 million years old and thus a useful guide fossil for the Early Cambrian. Olenellus had a well-developed head, large and crescentic eyes, and a poorly developed, small tail. The cephalon you see here was likely a moult as this particular specimen grew and shed his snug earlier head shield.