Page 40 - A Geology Walk up the Clyburn Valley

ISSUE : Issue 67

Published by Ronald Caplan on 1994/8/1

almost all the way to the summit of Beinn Franey. Because you can see, there's a ridge covered in deciduous trees, with some rock poking through it there. Then it seems to go back over that ridge and then up the cliff to the top of Beinn Franey. Now, cliffs are not very stable phenomena. They tend to get eroded away quite quickly. And I wouldn't be surprised if this whole face of the mountain is actually one large landslide that slid hundreds, or probably thousands, of years ago. The boulders themselves have fallen off the landslide itself. We can tell that these boulders have not moved far for a long time, because they're covered by a thick growth of different li? chens and reindeer moss. I suspect that if you turned some of these boulders over, you would see a much fresher and much less lichen-encrusted rock underneath them. They're here to stay, basically. A few of them have been turned over--peo- Lookingfor Something Different?... ALL UNDER ONE ROOF! • Cappucino • 1/ictorian (Prints df Cards • Photographs of Cape Breton Scenes • Bulk Ground Coffee • Crafts 'Poetry • Dried Flotver Arrangements • Custom Framing ... AND MUCH MUCH MUCH MORE • Unique Gift Ideas • VICTORIA R'SE "' BEAN BANK Cafe 243 Charlotte Street • Sydney pie have obviously been here and turned them around. You see the pink fresh gra? nite showing through there, on the under? sides of some of them. And I don't think those have fallen recently at all. The whole slope looks fairly stable. The trees are growing up through it. The trees have got good clean bark on the up-slope side, so the slope is no longer falling. Maybe most of it came down when the landslide happened initially. (We're not talking about something that took place in any kind of recorded memory, though, these slides....) No. There was one large slide that took place, we think, in 1904, on the North Mountain on the Sun? rise Valley. You see it as you drive along the Cabot Trail between Cape North and the warden's station at the Aspy Intervale. There's a big clear, cleaned-off ridge of granite showing through there. There have been some samples taken of trees that were killed in that landslide. And, counting the tree rings, they were able to date it back to about 1904. And we know that there was an earthquake in the area around 1904, so the two have been correlated together. The landslide probably happened at the earthquake. But that was the only known large landslide of this scale, in recorded history. This one, I would think, is prob? ably a few thousands of years ago. The origin of this whole mountain, of the rock that made this whole mountain, is what we have called the Cameron Brook gra? nodiorite. Cameron Brook is a little brook that flows down through Ingonish. And the Cameron Brook granodiorite is the name of this granite mass which forms a great cir? cular blob underneath Ingonish, extending inland a ways. The rock itself--we've been able to date it by analyzing the uranium and lead isotopes--it's 403 million years WE HAVE INFORMATION ON YOUR PROPERTY • AND YOU SHOULD KNOW WHAT IT IS! We have over 20 pieces of information on every number you see on this map, and we have a number on every property in Cape Breton, Richmond. Victoria, and invemess Counties. ~ A SERVICE WORTH INVESTIGATING ~ Cape Breton Land Information Central From BADDECK Department of Municipal Affairs Land Information Management Services Division ~ 500 George Place, Sydney, N. S. B1P 1K6 ~ CONTROL SYSTEM of concrete monuments for surveying BASE MAPS: Orthophoto for rural areas, Line Maps for cities, town, villages PROPERTY MAPS with boundary information and ownership information REGISTRY ASSISTANCE for government and private users Your Property Is Our Business • Ask Us About It TELEPHONE (902) 563-2280 or 563-2281 • FAX 563-0503

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