LANDFORMS CAUSED BY GLACIERS There are two major geology features that are seen geologically because of glaciers. These cluster into depositional phenomena and erosional phenomena. They are named differently based on where you live on earth. The landforms you see from erosion happen when glaciers slide over hard bedrock. Glaciers tend to pick up stuff along the way and drop them in various places that they travel to. Fine sediment is called rock flour. This is like the fine grit you'd use in a rock tumbler. This is how you get glacial polished rocks. Glacial striations are grooves made by larger pieces that scrape over rocky surfaces. Alpine glaciers can carve out their own valleys. They will not be V-shaped like streamcarved valleys but will be U-shaped instead. If you see two side-by-side valleys made from glaciers, you can see a ridge between them called an arete. The bowl at the top of the valley is known as a cirque, where the glacier carved out a section of the mountain. Figure 61 shows a cirque carved out by a glacier:
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