Wednesday, March 4, 2009

Theory of continental drift

Plate tectonic map by C. R. Scotese, PALEOMAP project www.sco- tese.com

This is how the earth is thought to have looked like 514 million years ago. The Avalon Peninsula of Newfoundland is positioned on the globe between "New England and Nova Scotia" and "England and Wales" where indicated on the map. Its more legible if you click to enlarge.

The Avalon Peninsula was part of what is known as "Avalonia". Its clear we've have drifted a considerable distance. In relation to todays world we were somewhere in the vicinity of South Africa. So, the rocks in the unconformity I posted in a blog entry last week were laid down in the southern ocean and through continental drift ended up in the North Atlantic.

The Avalon was part of Avalonia along with England, parts of Holland, Belgium and the Spanish peninsula and Morocco.

What is interesting to note is that Avalonia was part of a volcanic island arc something like Japan is today. The evidence for that is in the rocks of the Avalon Peninsula as the oldest rocks are of volcanic origin. The magma that fed those volcanoes is exposed on the surface now and is known as the Holyrood granite. Anyone driving along the Trans-Canada Highway between Butterpot Park and Holyrood can see the granite as pinkish outcrops.

Its hard to believe what interesting stories the rocks we paddle by can tell. I find it as interesting as the wildlife, scenery etc. Its all part of the same picture.

Tony :-)

2 comments:

Douglas Wilcox said...

I couldn't agree more Tony. Rocks are so interesting. When I did a lot of climbing I loved the smell of different rocks. Now when sea kayaking we see the bare bones of the earth. I believe that Scotland has been about a bit too!

Ty said...

Hey Tony,
I really never had an appreciation for the rock formations around our great province until I shot a documentary on the Tablelands with Harold "Hank" Williams. I've had several trip to the top of the Tablelands. While up there that Howlin'Wolf song, I'm Sittin' On Top Of The World" always comes to mind.

Ty