Page 40 - Curriculum Visions Dynamic Book

 This picture of the North African coast shows three processes of erosion in action that appear not to occur anywhere else in the Solar System. (1) Wind is blowing sand off the Sahara Desert into the Mediterranean Sea. (2) Rivers are bringing sand, silt, and mud to the sea from the land, forming the Nile Delta (the green triangular area). (3) The waves are carrying sand along the coast (the light-coloured sea to the right of the Nile Delta). All these processes will rapidly change the shape of the land.
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Erosion on the Earth
Erosion, the wearing away of solid rocks and the formation of fine materials such as soils, is a direct result of the water cycle operating on the land surface.
Although other planets have an almost unchanging surface, the land surface of the Earth is changing constantly, producing a wide variety of types of scenery. The water cycle also provides the water that living things need to survive on land.
The rock cycle
The movement of magma from the mantle to the surface and its erosion by the weather and oceans produce a continually changing surface. This transfer of material did not just happen once but has gone on time after time through the mechanism that transfers eroded material back to the mantle or back to the crust. Together all of these facets of landshaping make the rock cycle.
 The Earth’s surface is a balance of building and erosion. This is Cotopaxi Volcano, specially coloured to show height. Notice that the volcanic cone, which we are looking at from directly above, and which is produced by the buildup of layers, is scarred by deep valleys, the effect of water erosion.
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