Stob Coire nan Lochan, Glencoe Image from the SAIS Glencoe |
Tuesday, 29 March 2011
stob coire nan lochan
Saturday, 26 March 2011
Saturday, 5 March 2011
palimpsest
manuscript of text from Louis Agassiz |
Friday, 4 March 2011
the parallel roads of glen roy
A picnic near the Zermatt Glacier Louis Agassiz, from Etudes sur les glaciers, 1840 |
Hugi's hut on a medial moraine of the lower Aar glacier Louis Agassiz, Etudes sur les glaciers, 1840 |
Rocks polished and striated by a glacier Louis Agassiz, from Etudes sur les glaciers, 1840 |
One of his more significant discoveries was made in Scotland when Agassiz finally unlocked the mystery of the parallel roads of Glen Roy when he proposed that the "roads" were not of a marine nature, as was erroneously proposed by Darwin, but were in fact caused by the rapid damming by a glacier of a loch in the period of the Loch Lomond stadial (a mini ice age around 12000 years ago, and lasting for a brief 600 years) and it's subsequent melting, in three stages.
the parallel roads of Glen Roy |
I've spent much time walking and camping during winter in Glen Roy and have a favourite wild camp spot near Fersit. It's amazing to think that in the relatively recent past, this familiar valley would have been hidden under water, and my wild camp buried under a glacier near the head of Loch Trieg. I've seen the parallel roads marked on the Ordnance Survey maps, always rather assuming that they were indeed "roads", perhaps forestry tracks or some system of roads where a higher track existed to avoid boggy ground, but of course, that would eliminate the need for the lower tracks. Instead, they are completely natural, and lie on the horizontal, mapping, marking and measuring dramatic moments in the valley's past where the ice dams spectacularly broke and the glacial loch drained.
Stob Coire Easain (near Fersit), Dec 19th 2007 |
Subscribe to:
Posts (Atom)