Download chapter 4 - Miami Beach Senior High School

HOLT
CHAPTER 4
World
Geography
Today
Landforms, Water,
and Natural Resources
Section 1: Landforms
Section 2: The Hydrosphere
Section 3: Natural Resources
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HOLT, RINEHART AND WINSTON
Section 1
Landforms
HOLT
World
Geography
Today
Objectives:
 What physical processes inside Earth built up the
land?
 What physical processes on Earth’s surface wear
down the land?
 How do these physical processes interact to create
landforms?
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HOLT, RINEHART AND WINSTON
Section 1
Landforms
HOLT
World
Geography
Today
Plate tectonics create landforms:
Earth’s crust is made up of moving plates, which spread,
collide, and slide laterally past each other.
 Spreading plates form oceanic ridges undersea and
rift valleys on land.
 Colliding plates cause trenches and volcanoes
undersea and mountains on land.
 Plates sliding laterally cause fractures and
earthquakes.
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HOLT, RINEHART AND WINSTON
Section 1
Landforms
HOLT
World
Geography
Today
Forces on Earth’s surface:
Weathering and erosion shape the land.
 weathering—slow and hard to detect; includes
chemical and physical processes
 erosion—movement of surface material—by water,
wind, and ice—wears down land
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HOLT, RINEHART AND WINSTON
Section 1
Landforms
HOLT
World
Geography
Today
Tectonics and surface forces interact:
 Landforms are created through a combination of
forces.
 For example, a mountain range is formed by
tectonics, then weathered and eroded to create
valleys, alluvial fans, deltas, and other landforms.
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HOLT, RINEHART AND WINSTON
Section 2
The Hydrosphere
HOLT
World
Geography
Today
Objectives:
 In what forms and where do we find water on Earth?
 What are the causes and effects of floods?
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HOLT, RINEHART AND WINSTON
Section 2
The Hydrosphere
HOLT
World
Geography
Today
Water on Earth:
 Forms
 saltwater—97 percent of world’s water
 freshwater—most frozen in ice caps; less than 1 percent in
vapor and liquid form
 Where liquid fresh water is found
 surface water—in rivers, lakes, estuaries, wetlands
 groundwater—stored in soil and water table
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HOLT, RINEHART AND WINSTON
Section 2
The Hydrosphere
HOLT
World
Geography
Today
Floods:
 Causes—heavy rains, sudden snow melts; human
activity may contribute
 Effects—erosion, loss of vegetation, death and
destruction
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HOLT, RINEHART AND WINSTON
Section 3
Natural Resources
HOLT
World
Geography
Today
Objectives:
 Why are soil and forests important resources?
 What are the concerns about water quality and air
quality?
 What are some of the ways minerals are used?
 What are the main energy resources, and how are
they used?
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HOLT, RINEHART AND WINSTON
HOLT
Section 3
World
Geography
Today
Natural Resources
Importance of soil and forests:
 Soil is crucial for food production.
 Forests protect soil from erosion, provide species
habitats, and yield useful products.
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HOLT, RINEHART AND WINSTON
Section 3
Natural Resources
HOLT
World
Geography
Today
Concerns about air and water quality:
 air pollution—threatens air supply, creates acid rain,
damages the ozone layer, may contribute to global
warming
 water pollution— threatens clean water supply,
contributes to shortages
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HOLT, RINEHART AND WINSTON
Section 3
Natural Resources
HOLT
World
Geography
Today
Minerals
 Minerals are used in many processes and products,
including construction, jewelry, and manufacturing.
 Examples: building materials, airplanes, cans, glass.
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HOLT, RINEHART AND WINSTON
Section 3
Natural Resources
HOLT
World
Geography
Today
Energy resources
 Energy resources include fossil fuels—coal, natural
gas, petroleum—and uranium.
 Uses:
 uranium—energy for nuclear power
 coal—heat source; power for steam engines, mills,
electricity generation; dye making
 petroleum—lamp fuel; gasoline, diesel and heating fuel;
asphalt, petrochemicals
 natural gas—home and industrial heating; fuel
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