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Landforms. Mountains. Valley. Plateau . Plains. Hills. Mountains . They have steep top usually shaped up to a peak. Mountains occur more often in oceans than on land; some islands are the peaks of mountains coming out of the water.
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Mountains • They have steep top usually shaped up to a peak. • Mountains occur more often in oceans than on land; some islands are the peaks of mountains coming out of the water. • Over long periods of time, mountains are created by tremendous forces in the Earth.
Mountains Cont. • Mountains are formed by • Volcanoes • Erosion by wind, rain, and ice • Disturbances or uplift in the earth's crust caused by the movement of tectonic plates
Valley • A valley is a hollow or surface depression of the earth bounded by hills or mountains, that slopes down to a stream, lake or the ocean. • A valley is formed by water and/or ice erosion. • At the bottom of many valleys is fertile soil, which makes excellent farmland.
Valley Cont. • The bottom of a valley is called its floor. • The part of the floor along riverbanks is called flood plain. • A valley's sides are called valley walls.
Plateau • A plateau is a large highland area of fairly level land separated from surrounding land by steep slopes. • Plateaus are formed by either volcanoes or erosion. • Low plateaus are often farming regions, while high plateaus are usually suitable for livestock grazing.
Plains • Plains are broad, nearly level stretches of land that have no great changes in elevation. • Plains are generally lower than the land around them; they may be found along a coast or inland.
Hills • Hills are elevations of the earth's surface that have distinct summits, but are lower in elevation than mountains. • Hills may be formed by a buildup of rock debris or sand deposited by glaciers and wind. • Erosion forms hills by carrying away all of the soil on a mountain.
Hills Cont. • Volcanoes can form hills when volcanic ash is spewed through the air during an eruption. Then after the eruption, the lava hardens and builds up a thick layer of lava rock. The ash falls on the hardened lava causing a layer of ash to form on the hill. • Lastly, a hill can be created by humans digging soil up and dumping it in a giant pile.
Rivers • A river is a larger body of water that flows aboveground, in a particular direction, and usually has a large volume of water in it. (This varies, of course, according to rainfall and/or snowfall totals). A river will always have more water in it than a stream. Rivers often flow into other bodies of water. For instance, the Mississippi River flows into the Gulf of Mexico.
Gulf • A gulf is a large area of an ocean that is partially enclosed by land. Looking at a map of the Gulf of Mexico will help you understand this idea. A gulf is a sheltered area of shoreline into which water flows and gathers.
Lake • A lake is a large body of water that is totally surrounded by land. A pond is the same thing, only with less water and a smaller diameter.
Ocean • An ocean, which is the largest body of water on Earth, is generally thought of as having no boundaries. The Atlantic Ocean has Europe and Africa to the east and North American and South America to the west, but the ocean is still considered to have no boundaries because to the north and south is more water.
