Erratic behaviour?

A glacial erratic on the Coquitlam River.

Hopefully, you got my pun.  The term erratic is often used to describe someone's behaviour that is unusual and unpredictable.  However, it is also a geological term referring to a large rock which seems out of place, usually an isolated feature.  Erratics are post-glacial relics, prominent signs of a retreating mass of ice.  Sometimes boulders will fall onto a moving glacier and will be carried along with the flow and then deposited.  Other times these enormous testaments of mass movement are literally plucked from the rockface, being scoured by the eroding embrace of the ice.

I have always had a fascination with glaciation, both alpine and continental.  I grew up in southern Ontario where there are tremendous numbers of glacial artefacts.  Drumlins, kettles, eskers, and endless deposits of moraine cover the landscape.  I remember going on a school field trip to explore some of these features in Grade 9.  I was in awe at their majesty and still am inspired when I see evidence of their existence. 

It was when I moved to Alberta though that I got my first taste of alpine glacial features.  Cirques, aretes, U-shaped valleys, and horns all declared their presence.  I took a course on geology through the University of Calgary and went on a field trip to the Porcupine Hills.  There I was reunited with the old familiar features I knew in Ontario.  Tremendous, spectacular, exhilarating!

Most of Canada was covered by the ice sheets which created much it's current surface.  There are a few places which were not affected by the moving mayhem.  One of those places is Cypress Hills, which is located at the southern border between Alberta and Saskatchewan.  I have never been there but hope to explore its wonders some day soon.

Thanks for reading.   www.ericspix.com   Eric Svendsen