Thursday, March 12, 2015

The missed summit, James Hutton's window into the depths of time...and an antidote to our failure.

The goal: Arthur's Seat, Edinburgh's inner city mountain.
We had hoped to head out into Cairngorms National Park but wind gusts of 100 mph were forecast. The Mountain Weather Information Site (MWIS) said that mobility would become "tortuous". Our Plan B was sounding like a much better option: we would take the train to Edinburgh...and hike up to the top of an ancient volcano. That would be easy enough.

After a very pleasant hour on ScotRail, to Waverley Station in downtown Edinburgh, we walked along the Royal Mile to the trailhead at Holyrood Park, the 650 acre piece of highland landscape - right in the middle of the city.

The area was once a 12th century hunting estate. In 1541, it was established as a park by James V of Scotland. His only surviving child became Mary, Queen of Scots - gaining the throne at only 6 days old. Most important for our activity, however, was that it is the site of a volcano which was active about 340 million years ago, in the early Carboniferous times. The plan was to hike to the highest point, Arthur's Seat, rising just over 800 feet above the city. Robert Louis Stevenson described it as "a hill for magnitude, a mountain in virtue of its bold design". It would be perfect.

The skies cleared momentarily...and the winds blew.
Perfect...except that the forecast winds had followed us to Edinburgh. After walking uphill for about forty-five minutes, the sudden and violent wind gusts that were measuring up to 67 mph on the little handheld anemometer began to feel, well, "tortuous". A small group of walkers, in their twenties, smiled grimly as they passed us on the trail. They were going to push on. We'd had enough, the winds were blowing most of the fun out of this little expedition. We'd come this far...this close...and we were clearly going to fail to achieve our goal.

We needed a Plan C to assuage our disappointment. Aha, the Salisbury Crags. The broad path between the foot of the crags, and the steep talus or scree slope is called the Radical Road, created by unemployed weavers after the "Radical War" of 1820. It would make a great return route, providing a narrow circuit for the day.

The "Radical Road", between the base of the crags and the talus slope.
Scotland's capital, at the foot of Holyrood Park with the Castle at far left.
The "crags" are composed of dolerite and are part of a volcanic shelf, called a sill, created 25 million years after the volcano became extinct. This once-molten rock was squeezed between layers of horizontal, sedimentary rock.

Pressures in the earth's crust caused the shelf of rock to split and be forced upwards, tilting, and coming to rest at a 25º angle towards the east.

Formed, uplifted, tilted, eroded...the process continues.
Glaciers subsequently moved over the land, scraping away the sedimentary rock, leaving the hard volcanic rock behind. Presto, the Salisbury Crags!

Joan, striding purposefully towards the base of the crags.- they were mesmerising.
It was here that the "father of modern geology", James Hutton, found evidence that the earth was much older than ever imagined. Up to that time, geologists had thought that rocks were formed by a process of sedimentation, in water, and that sedimentary rocks were the "youngest" type.

Rock climbing is permitted in the South Quarry.
Hutton proved that rocks are also formed as molten liquids. Here, the liquid dolerite had pushed aside older rock layers, clearly demonstrating that rocks are formed at different times by different processes.


Archbishop Ussher's then-accepted "age of the earth" at some 6000 years would be pushed back to a startling 4.5 billion years. Hutton changed the way people thought about the planet. The hard-working archbishop (who must have had a little too much time on his hands) had actually worked out the "birth of the earth" to the minute - 6 pm, on October 22, 4004 BC. Wouldn't he be surprised! :)

Following our "failure" to reach the summit of Arthur's Seat, it turned out to be a truly remarkable day, humbling in so many ways. This is truly an extraordinary planet, unimaginably old. James Hutton's theories of geology and geologic time give perspective to our brief lifespans as human beings. All the more reason to make every moment count. All the more reason to go in search of and value every possible experience out there. All the more reason to set free our inquiring minds about the world around us.

Tiny dots of walkers (extreme left) give scale to the crags.
“Failures are finger posts on the road to achievement.” 
- C.S. Lewis

Plan C, the Salisbury Crags, was much more than an antidote to our missed summit. It was a reminder that failure is only one small step on the path to new discoveries.

We must stay on that path...always.

4 comments:

  1. Great post Duncan - and where was the "failure"?! Sure, a hill has only one summit but as you've shown it has thousands of points of interest :o) James Hutton is a hero of mine, a truly remarkable and inquiring mind and a tough outdoorsman....

    Warm wishes to you both

    :-)

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    1. Haha! No failure at all.Thanks for that, Ian. He's a hero of mine too. I learned about him first from my dad when we would go for long walks in southern Ontario, examining Precambrian rocks along the way. Joan and I also visited Dynamic Earth a couple of weeks ago, reminded me again all about Hutton - just had to get to Holyrood Park after that. It was a great day. Warm wishes to you. Duncan.

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  2. Hi Duncan that was a great day out. I used to live in Edinburgh and have several times been blown off the seat. You really must come to Arran sometime and paddle right past Hutton's unconformity! :o)

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    1. Hi Douglas, it was a great day out and you will know very well the wind up there. Yes, Arran would be wonderful, we'll look forward to getting there. It would also be interesting to see the unconformity at Siccar Point, from Hutton's offshore perspective. It's on the bucket list. :) Warm wishes, Duncan.

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