Extreme landscapes: Glacial Processes

So from the previous blog we know that glaciers move, they ate massively heavy and as they move they change the land that they travel over.

The main erosional processes are Freeze/thaw, plucking and abrasion.



Freeze-thaw is when melt water or rain gets into cracks in the bed rock, usually the back wall. At night the water freezes, expands and causes the crack to get larger. Eventually the rock will break away.

Plucking is when melt water from a glacier freezes around lumps of cracked and broken rock. When the ice moves downhill, rock is plucked from the back wall. It leaves behind a jagged landscape.

Abrasion is when rock frozen to the base and the back of the glacier scrapes the bed rock. This causes the wearing away of the landscape as the glacier behaves like sandpaper. It leaves behind smooth polished surfaces which may have scratches in them called striations. Striations are carved out by angular debris embedded in the base of the glacier.

In terms of teaching glacial processes my view is that it should be linked to the landforms created so that they is something tangible to examine. The next blog will show the formations giving pictorial examples. I have found some great video's online but I am yet to work out how to upload them to the blog. These would be very helpful in providing a visual explanation. Also, if it were possible a field trip to the lakes would be great to show the students the processes and the results....money permitting of course!