Originally uploaded by Mic2006.
Short of having your own kayak or private vessel, the glass bottomed boat tour is the only way to access the wave-swept islands off the coast of the Bruce Peninsula. Here, the explorer, amatuer geologist and geography enthusiast can see Ontario’s rock and it’s erosional formations at their finest. There are a number of complex issues that have combined to create a landscape that is both rugged and sublime. All around the edge of the islands there are cliffs and ancient cedars that tumble down to deep blue bays and seething, foam flecked shorelines.
Ontario’s most dominant geographical feature, the Niagara Escarpment dips beneath the water here. Georgian Bay and Lake Huron now connect in a wild storm tossed channel. Over the last 12 000 years, (since the disappearance of the last great glacier) the lake levels have fluctuated quite drastically. Where once the waves scoured away cavities along the shoreline, the caves are now left exposed as mysterious black holes high up in the cliffs. Some are as much as 40 feet above the present day lake level.
These eroded cavities abound all along the edge of the Bruce Peninsula and around its many islands. They are quite uniquely different from the typically imagined “solution caves” in that they have generally been formed by wave action along some sort of weakness in the rock.
The most famous of these caves is “The Grotto” near Cypress Lake. It formed along a structural weakness and the roof is comprised of a relatively less erodible fossilized reef. A pool within dips down to a depth of over 30 feet and from its luminous glow explorers can see that it connects to the bay outside. This beautiful place is a short hike along the lakeshore. (See my book, “Rockwatching; Adventures Above and Below Ontario” in the sidebar to the right, it has a chapter that guides you along that hike).
The Georgian Bay sea caves have been formed in the area’s cap rock, the strata of the “Guelph Formation”. It is a dolostone that formed in the late Silurian Age. at that time the area was submersed beneath a warm, clear sea, rich in lifeforms that are still preserved in the fossils of that strata. The Guelph Formation is a mustardy-tan colored stone beneath the water but on the surface it weathers grey and is generally stained with orange scabs of lichen.
Another interesting exposure of the Guelph Formation is in the Elora Gorge, just north of the town of Guelph. Possibly its most recognized use has been in the endearing statue of the famous weather prognosticator, “Wiarton Willie”. His likeness is celebrated in an eight foot high statue along the edge of the Wiarton Marina. (More on Willie later)
This image of the Flowerpot Island sea caves was taken from the deck of the “Blue Heron V”. The cave can be easily visited by tourists and hikers; it is but one of many such features that pit the landscape. Maggie and I were dropped ashore by zodiak (At Beachy Cove) and a twenty minute stroll along a beautiful woodland trail bought us to the mouth of the cave. When booking your tour in Tobermory you can arrange to be dropped off on Flowerpot Island and then collected later in the day. There are six campsites for those who wish to stay the night but booking must generally be done well in advance of your visit.