6 July 2012

Friday fold: scenes from the trail to Bertha Lake

Posted by Callan Bentley

Given that I’m leaving tomorrow for the Canadian Rockies, I’ve been inspired to look through some of my photos from last summer, and to realize how few of them I’ve blogged so far. So let me show you some folded things today that Lily and I saw the afternoon we arrived at Waterton Lakes National Park in southernmost Alberta:

Here’s a fold on the side of a mountain on the other side of Upper Waterton Lake:

Zooming in to the relevant portion:

With bedding sloppily annotated:

These are Mesoproterozoic Belt Supergroup strata (the Canadians call them the Purcell Supergroup, but it’s the same stuff you see a few miles south in Glacier National Park, Montana).

Sure enough, there are even stromatolites present:

That’s not really a fold, since it’s a primary structure rather than a tectonically-induced deformational feature.

But what about this?

That’s a J-shaped tree-trunk. It’s symptomatic of creep, that slowest form of mass wasting. I’ve only seen one better example of such a thing in my travels.

Happy Friday – and enjoy the next couple of weeks, when posting on this blog will be lighter than normal.