4. Ice

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Ice
Ice in the form of glaciers can also change landforms. Glaciers are thick sheets
of ice, formed in areas where more snow falls during the winter than melts during the
summer. Glaciers seem to stand still, but they actually move. Because of a glacier’s
great size and weight, it erodes everything under it. Glaciers erode sediment from
one place and deposit it in another.
Glaciers are major forces for forming new landforms. As the glaciers of the last
Ice Age moved forward, they pushed mounds of rock and soil in front of them. When
the glaciers melted, they left behind at their
lower ends long ridges of soil and rock.
There are two kinds of glaciers. Valley
glaciers are found in high mountain valleys.
They flow slowly down mountainsides,
eroding the mountain under them and
forming U-shaped valleys. Only a few valley
glaciers remain in North America. And even
those are melting rapidly.
Continental glaciers are ice sheets that
cover large areas of Earth. They cover almost all
of Greenland and Antarctica today. But
thousands of years ago, when the climate was colder, continental glaciers covered
Europe, Canada, and the northern United States.
√What are glaciers?
Name two types of glaciers.
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