Tuesday, August 10, 2010

Varved Clay today on the road

A Glacier was here, and I saw the art that it left behind. map

Varved clay is an accumulation in proglacial lakes of yearly-couplets of lacustrine beds called varves: during the summer, silt (light gray in color) settles and accumulates and in the winter, when the lake is ice bound (frozen over), clay-sized material (dark gray in color) settles and accumulates.

I was first introduced to varved clay when I was kayaking on the Fredrickhouse Lake map.
There is an eroding shoreline that is stripped with different soil layers and colours. When I got home and did some reading I discovered varved clays.

Later I would work for Ontario Parks and find out the location I had been looking at was actually a non-operating Provincial Park. Fredrick House L. Provincial Nature Reserve March 1985. map

Here is a very interesting paper by the National Research Council Canada. December 1954 some
of our tax money produced a paper called "A Laboratory Study of Varved Clay from Steep Rock Lake". I am guessing it is this lake north of Atikokan, Ontario.

You can see information on the Steep Rock Lake Mining and see a picture of the lake with no water in it here.