Landforms, Water, and Natural Resources

1. CHAPTER 4 Landforms, Water, and Natural Resources Section 1: Landforms Section 2: The Hydrosphere Section 3: Natural Resources

2. Section 1Landforms 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?

3. Section 1Landforms 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.

4. Section 1Landforms 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

5. Section 1Landforms 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.

6. Section 2The Hydrosphere Objectives: • In what forms and where do we find water on Earth? • What are the causes and effects of floods?

7. Section 2The Hydrosphere 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

8. Section 2The Hydrosphere Floods: • Causes—heavy rains, sudden snow melts; human activity may contribute • Effects—erosion, loss of vegetation, death and destruction

9. Section 3Natural Resources 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?

10. Section 3Natural Resources Importance of soil and forests: • Soil is crucial for food production. • Forests protect soil from erosion, provide species habitats, and yield useful products.

11. Section 3Natural Resources 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

12. Section 3Natural Resources Minerals • Minerals are used in many processes and products, including construction, jewelry, and manufacturing. • Examples: building materials, airplanes, cans, glass.

13. Section 3Natural Resources 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