First, remember the physical size of the Niagara Escarpment:
Now, take a look at the Ontario Roads map of the region around my home base in Wareham:
West Central Ontario, range circles (10 km) centred on Wareham |
Did I say FLAT? What the ground around here looks like! |
I felt the only hope of finding anything at all would be at one of the rare places where erosion had exposed the base limestone of the Escarpment.
Four locations are indicated (yellow circles) on the map above, in the order I looked at them. For each I was looking for places where the under laying rock was exposed.
ONE - Belfountain
This point, just south of Orangeville and west of Highway 10. is where an ancient river had cut through the loose gravel cover to expose the limestone. There was enough water moving originally to both cut the rock, but also to throw refrigerator sized blocks around. Today there is a waterfall down one exposed face of this cut.
From the waterfall, we travelled about 200 m down the path that runs along the top of the cut on the north side. Eventually this trail runs down to the bottom of the cut.
One feature there is a pile of larger stones, obviously cut from further upstream at some point in the distant past. These have been tossed into a pile along the south bank, in a fairly localized area. It looks like the force of water could carry them this far, but no further. These blocks are of a different limestone than those in the rock cut at the same area.
Showing the limestone face, part way up the pile of jumbled rocks (to the right here) |
Kelly standing beside one of the large rocks showing iron staining |
Iron staining on rock surface - bag is 4 1/2 inches |
Iron staining appearing to form a line through the pile (?) |
On closer examination, what was happening was that these rocks had a smaller amount of iron contained within the matrix. As the water seeped into the stones, then later evaporated from the surface, there was a small amount of iron forming like a scale on the very surface. Although I did flake off a couple of fragments as samples, it was clear that the 'iron' was only a thin film on the surface. At best only one or two mm thick. More like pulling off a surface layer of rust flakes.
(Stay tuned for part Three)
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