Glacial Landforms Essay

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Assessment- Glacial Processes and Landforms A glacier is formed when snow accumulates in a dip in a mountain or hill. The snow will build up in the dip; this will lead to the pressure of the compacted snow to form ice. This ice’s weight forces the land beneath it to become compact, and enlarges the dip, this is called a hollow. The ice that accumulates becomes larger to form a glacier. The glaciers weight forces itself downhill. As it moves downhill it carves the landscape because of the pressure caused by the great mass of the glacier. The glacier will continue down hill forming a U-shaped glacial valley as it carves its own path. There are other methods that a glacier uses to erode and shape the valley such as, plucking, abrasion, and freeze-thaw weathering. Plucking is when a glacier freezes onto a rock and pulls it away from the land as it moves. Abrasion is when the rocks (and other materials) that have been previously plucked by the glacier are carried by the glacier and is then rubbed against the sides and floor of the valley, like sandpaper. And finally, freeze-thaw weathering occurs in rocks that have many cracks and joints in them, and where temperatures are usually around freezing point. Water (from beneath the glacier), called melt water, gets into the small cracks in the day, and freezes and expands in the night. This puts pressure on the crack, and expands it wider. After the ice has melted, more melt water will get in, and it will freeze over and over again. This eventually makes bits of rocks come away from the surface. Many landforms and moraines are left behind by the glacier. Moraine is sediment deposited by a glacier. There are four types of moraine; lateral, medial, ground and terminal moraine. The model shows only three. It shows lateral moraine, this is sediment found a long side of a glacier made up of fragments of weathered rocks
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