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Shaping
20
20 Earth’s
Surface
Weathering and erosion tend to sculpt, or wear down, the land, sometimes
leaving behind rock structures of more resistant rocks such as those you
can see here.
CORE CONCEPT
The surface of Earth is involved in an ongoing process of destruction
and tearing down of higher elevations.
OUTLINE
20.1 Weathering, Erosion, and Transportation
Weathering 20.2 Weathering Soils
Physical, chemical, and 20.3 Soils Soil is a mixture of the products
biological processes that break 20.4 Erosion
Mass Movement of weathering—sand, silt, and
up or crumble solid rock are
Running Water clay—and humus.
called weathering.
Glaciers
Wind
Science and Society: Acid Rain Erosion
Erosion People Behind the Science: Gravity, running water, glaciers,
Erosion is the removal of rock John Wesley Powell and wind are agents of erosion.
and mineral fragments, clays, 20.5 Development of Landscapes
Rock Structure
and solutions that have been Weathering and Erosion Processes
produced from solid rock by Stage of Development
weathering.
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