Yosemite Valley, California is an example of a U shaped glacial valley
Yosemite Valley California: A classic U-shaped glacial valley
Yosemite Valley from the Yosemite Falls trail. Yosemite Valley is a glacial valley in the Sierra Nevada mountains and the focal point of Yosemite National Park. The Valley is drained by the Merced River.
Glaciers have had a profound effect on the topography (lay of the land) in some areas, as in the northern U.S. You can imagine how a billion-ton ice cube can rearrange the landscape as it slowly grinds its way overland. In this picture you can see the bowl-shaped valley in a glacial valley in California where an ancient glacier forced its way through the landscape. Many lakes, such as the Great Lakes, and valleys have been carved out by ancient glaciers.
A glacier sculpts the land in ways different from running water. A river occupies a small U-shaped channel in the bottom of a V-shaped valley. A glacier carves the whole valley into a U-shape. The upper end of a river is a small stream in a small swale that merges with the drainage divide. The head of a glacier-carved valley is a steep-walled bowl or cirque. Glaciers are not as easily influenced by rock hardness as are rivers. They tend to bulldoze ahead, straightening out twisty river valleys.
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