Glacial Striations

Do you like ice cubes in your glass of water or milk?  Most of us enjoy a drink of coffee or tea steaming hot.  

When out on a walk yesterday it was good to look forward to a warm house.   The feel of the air was zero degrees. Layers of warm clothing were needed. It helped to have almost no movement in the air. A wind would have convinced me to stay inside.

One of the attractions of the Boundary Waters Canoe Country is clear water lakes where you see down through the water to the rocks that form the basin of the lake/

Ice now covers those lakes. Come spring time Ice begins to melt close to the shore with a south exposure.  One avoids walking there for fear of a cold wet foot and leg.  One can stay on the exposed rocks of an island and inspect the slabs of rock that begin to warm as soon as the sun begins to move higher in the sky.

Often there will be gouges in the original Green Stone that is a most ancient rock formation. Upon further inspection those gouges in the rock appear to be scratches, some quite deep.  All going in the same direction – northeast to southwest. On a rock island one can track those scratches and discover history written in the stone and left for us to do the reading. 

It is very difficult to scratch solid rock.  Whatever did the scratching must have been heavy – very heavy. Some immense force was doing the pushing.

Geologists who study the surface of the earth have concluded that there have been several ice ages when large portions of earth have been ice covered. 

 One glacier covered much of Canada was moving south across Wisconsin and Minnesota. As the ice mountain of a glacier move everything was pushed ahead. Huge boulders were like pebbles carried along by the ice. Under it all was the Greenstone of ancient times. When the boulders and rocks struck the greenstone, the process was like a file digging into the greenstone leaving scratches now evident to us humans. We can tell that the force of the ice mountain was going from the northeast to the southwest here in northern Minnesota.

A person can run a hand over the scratches in the greenstone and imagine a bit of what that slow-moving force was doing in reshaping the earth.

When I go outside in the present weather my mind imagines what it would be like to live at the edge of glacier.  In our imagined claims to control nature we forget that in the long run, nature rules.

12-27-2017