The Geosphere
The Earth as a System Consists of: - Geosphere - Hydrosphere The Earth is a system of 4 interacting components. Consists of: - Geosphere - Hydrosphere - Atmosphere - Biosphere
The Geosphere Composition The solid part of the Earth (rocks, minerals, soil, etc.) Most of the geosphere is below the surface What is it? Lithosphere Cool, rigid layer that includes the crust; divided into plates Asthenosphere Flexible layer of the mantle that flows slowly, allowing plates above it to move Outer Core Liquid nickel and iron Inner Core Solid nickel and iron
Look at the world map. Does anything look like it could fit together like a puzzle?
The Geosphere Plate Tectonics Pangaea – Wegener’s idea that all of Earth’s continents were joined into one giant landmass 200 million years ago.
The Geosphere Plate Tectonics The tectonic plates ride atop the asthenosphere, moving in different directions Boundary Movement Result Convergent 2 plates move together Mountains, volcanoes, earthquakes Divergent Transform
Convergent Plate Boundaries Continental-continental Oceanic- oceanic Oceanic-continental
The Geosphere Plate Tectonics The tectonic plates ride atop the asthenosphere, moving in different directions Boundary Movement Result Convergent 2 plates move together Mountains, volcanoes, earthquakes Divergent 2 plates move apart Ocean ridges (volcanic), rift valleys, earthquakes Transform
Divergent Plate Boundaries Mid-ocean ridge Rift Valley
The Geosphere Plate Tectonics The tectonic plates ride atop the asthenosphere, moving in different directions Boundary Movement Result Convergent 2 plates move together Mountains, volcanoes, earthquakes Divergent 2 plates move apart Ocean ridges (volcanic), rift valleys, earthquakes Transform 2 plates slide past each other Faults, earthquakes
Transform Plate Boundaries
The Geosphere Plate Tectonics Global Earthquake Distribution Global Volcano Distribution
Destruction, injuries, death The Geosphere Earthquakes Volcanic Eruptions How does it happen? Earth’s crust slips along a fault (crack in the crust) Local Effects Destruction, injuries, death Global Effects Tsunamis Which of these geologic hazards poses the greatest threat to the environment? Why?
The Geosphere Destruction, injuries, death Tsunamis Earthquakes Volcanic Eruptions How does it happen? Earth’s crust slips along a fault (crack in the crust) Pressure of magma inside the volcano becomes so great that it blows open the solid surface. Local Effects Destruction, injuries, death Destruction, injuries, death, mudflows, *improved soil fertility Global Effects Tsunamis Ash clouds from major eruptions can block sunlight & change drop the average global temp.
The Geosphere Erosion Rocks on the surface are changed by wind, running water, and weather. Erosion is the removal and transport of weathered surface materials. Over long periods of time, erosion can wear away entire mountains and produce spectacular landforms.
How is the land in this picture being used?
How We Use Land Urban land = land covered mostly with buildings & roads and containing 2500 or more people. Rural land = land containing few people & large areas of open space.
How are each type of land cover important to people? Think-Pair-Share How are each type of land cover important to people?
The Urban-Rural Connection Think About It… Are people dependent on the resources produced in rural areas? Ecosystem services – resources produced by natural & artificial ecosystems
Development of Marginal Lands Some suburbs have been built on land that is not well suited to support buildings. This land is prone to landslides because it is unstable Ex: Los Angeles, Mexico City
Urban Environmental Condition Heat Islands – increased temperature in a city Why? - roads & buildings absorb more heat than vegetation Effects? – local weather patterns change, more rainfall in cities Pollution of air, water, & land
Urban Planning Land-use planning is essential for pleasant urban living experiences. Ex: Transportation in cities involves mass transit systems (buses, trains) Mass transit saves energy, reduces traffic, lowers air pollution, & limits the loss of land to roads & parking lots Open space is set aside in urban areas for recreational enjoyment (parks, gardens, bike paths, hiking trails) Open spaces absorb CO2, produce oxygen, filter pollutants, lower temperatures, absorb rainwater
Land Management & Conservation Land Type What is it? How is it used by people? What are the problems/threats to this land? How can it be maintained / protected? Farm land LAND USED FOR CROPS AND FRUITS FOOD URBAN DEVELOPMENT FARMLAND PROTECTION PROGRAM Range land LAND THAT SUPPORTS VEGETATION (GRASSES) GRAZING LIVESTOCK OVERGRAZING PUBLIC RANGELANDS IMPROVEMENT ACT Forest land LAND THAT SUPPORTS TREES WOOD, LUMBER, PAPER, ETC. DEFORESTATION (CLEARING WITHOUT REPLACING) REFORESTATION Parks & Preserves LAND PROTECTED AGAINST DEVELOPMENT RECREATION, WILDLIFE REFUGE, PROTECTING ENDANGERED SPECIES INCREASED DEVELOPMENT, VISITOR DESTRUCTION & LITTERING US WILDERNESS ACT – PROTECTS FROM EXPLOITATION
Designing A Community You are a land-use planner. Design a model community that is to be home for 1000 people. Name your community & tell us where in the world you are located. Sketch your plans for the following: Housing Commercial Transportation routes Open spaces Community services (electricity, water, trash collection, police & fire protection, schools, hospitals, etc.) Where will resources come from?