Sunday, March 27, 2011

Epic Dunes Snowshoe

Yesterday was a BEAUTIFUL day in Grand Marais. Temperatures were in the low 20s and it was sunny. Friend, Helen, from Marquette came to visit so that three of the four of the Grand Canyon hikers could get out for some exercise. So Helen, Wendy, me along with another friend, Kim, started at Sable Lake.

We walked down H58 west for a ways and then headed up into the dunes. We climbed a valley that offered this nice view of white birches.

When we finally reached the top of the first dune, we looked back south to see what I think is the Munising moraine. As the glacial ice receded around 10,000 years ago, it stopped at various points and built up land form features known as moraines--ridges that vary in height and composition depending on the length of time the ice remained at a particular point and on the materials that were eroded. Moraines are typically rolling landforms, higher than the surrounding countryside. They are composed of glacial till--a sediment made up of rocks and stones, laid down as the ice rapidly melted. These landforms formed as the ice was temporarily stationary, while internally the ice brought sediment forward and continuously deposited it at the margin. Alternatively, end moraines formed as a glacier readvanced and "pushed" soft sediment in front of it, creating what is often called a "push moraine". The outermost end moraine is given the special name "terminal" end moraine. All others are referred to as recessional moraines, since they mark a recessional position of the ice margin. The Munising moraine was first thought to be an end moraine, but scientists now think that it is a recessional moraine.

Once we were in the dunes, we headed north to the Lake Superior shoreline. Officially, they say the Grand Sable dunes encompass five square miles. I have to tell you that it seems like they are bigger. Here are Helen and I in the middle of the dunes.

Here are some dune scenes....

At several spots we ended up on tall dune ridges. The easiest, safest, and most fun way to get down is to slide on your butt. Actually, I found that by sliding on one hip you can use your elbow as a sort of rudder. Of course, it is important to keep your snowshoes up off the snow while sliding. Here is Helen at the end of her slide. The second picture below has a red arrow that shows the path of our slide.

Here is a neat snow melt pattern.

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