Sunday, December 16, 2012

IS there Iron? - Part 3

As a refresher, this is a continuation of the series report on field walking in November. Generally not a bad time for this, the vegetation has died back, the bugs are gone, the water levels often lower. This year (despite claims by fools in America) the impact of global climate change (and Canadian warming) was clear. Mid November and still no snow!

IS there Iron - Part 1
IS there Iron - Part 2
North Erie Shore - Bog Iron

Take a look at the map of the region around Wareham again:

10 km range circles
Location 1, Bellfountain, was discussed in Part 2.

A couple of days later I had occasion to run up to Collingwood (look NE of Wareham, along Georgian Bay). On the way back I ran on a rough diagonal line back to Wareham, more or less along County Road 32. This lays along a valley cut into the edge of Blue Mountain. Note that Blue 'Mountain' is really the slope of the edge of the massive limestone block of the Niagara Escarpment - not a true 'mountain'. 
I did see at least one spot that looked like it was at least worth a closer examination when seen from the road. This was a very sharp cut of a stream bed that exposed the underlaying rock. Massive problem however - hunting season! It was late afternoon, and the road was dotted with trucks unloading men in orange jackets with rifles. (I was furious at this, the area was well sign posted as being provincial park land - 'No Hunting' signs all over.) I most certainly was NOT going to chance leaving the roadway!

Location 2 - Chepstow

A week later, I paid a visit to my close friend David Robertson, who had seen potential signs of iron south of his home / shop near Chepstow (look to the far west side of the map).


The spot was a rock cut into a shallow valley, which had a swampy bottom with a small stream running through it. David's thought was that this bottom land might contain bog iron ore, deposited from what he thought looked like iron contained in the surrounding rock.
On closer examination, the staining on the limestone was in fact a reddish yellow clay deposit, washing out of the stone. Although the colour was likely do to traces of iron oxide, there was only minimal amounts of iron present. Certainly not enough to constitute a useful ore.
(And truthfully, it was absolutely pissing down a hard cold rain - we were soaked to the skin in the five minutes at the rock cut alone. Retreat for hot wiskeys was called for!)

Location 3 - East Owen Sound.

Another place where the parent rock of the Escarpment is cut through is at Owen Sound, about 45 minutes drive north of Wareham. About mid November, I had to run up that way for steel supplies. I drove over to the east of town, where again the rock is exposed. I ended up not getting out of the truck for a closer look. The stone was very similar in appearance to that seen in the image above - a light yellow porous limestone.

Location 4 - East Markdale

On the way back home, I travelled down via a series of dirt roads more or less straight south from the Owen Sound area. The table of the Dundalk Plateau is cut by a number of deep river valleys (originally glaciers) through that area. The Beaver Valley is the one just to the north of Wareham, running SW to NE, from roughly Flesherton towards Thornbury on the map.

(Sorry about the image quality on these next)

Limestone at the edge of the valley cut
Tumbled blocks at the foot of the cliff
As you can see from the image, the stone here is a more solid, hard, dark to medium grey limestone. There was no evidence of iron staining at all. Although the heavily moss covered rocks were quite magical in appearance, there is no iron present.

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