1. Dynamic Earth Earth Systems, Plate tectonics, Layers, Earthquakes, Valcanoes

2. Earth as a System  Four parts:  Geosphere (rock)  Mostly located in Earth’s interior  Atmosphere (air)  Hydrosphere (water)  Oceans ¾ of the globe  Biosphere (living)

3. Layers of the Earth  Crust, Mantle, Core  Lithosphere  the crust and the upper mantle  Divided into plate tectonics  Asthenosphere  Plastic, solid layer of mantle made of rock  Allows tectonic plates to move on top of it (slow)  Mesosphere  Lower layer of the mantle between the asthenosphere and outer core

4. Continued…  Outer Core  Dense, liquid layer  Outer shell of core made up of liquid iron and nickel  Inner Core  Sphere of solid nickel and iron at center of the Earth  Earth’s inner and outer core make up about 1 / 3 of earth’s mass

6. Plate Tectonics  Continental Drift  Fossil Evidence of the same kinds of animals living on separate continents.  The types of rocks found on each continent today show similar strata and ages. Mt. Ranges on the coast of West Africa disappear then suddenly reappear again on the coast

7. 225 Million years ago

8. 150 million years ago…

9. 90 million years ago…

10. 35 million years ago…

11. Present…

12. Plate Movements  Divergent:  Sea Floor spreading: where new land is created. Occurs in the ocean (mid-ocean ridges)  Transform:  As 2 plates slide past one another friction builds. (Earthquakes)  Convergent:  Plate collisions  Subduction: plates push up continental plates (Volcanoes)  Uplift: Mountains form

13. Plate Movements

17. Convection Currents  Occurs in the magma  Magma is heated, becomes less dense and rises, then cools, more dense and sinks  Heating, cooling (rising, sinking) creates currents = plate movement

18. Earthquakes

19. Divergent Plates

20. Volcanoes: Ring of Fire

21. Volcanoes  Shield:  Large, broad with a crater at the top  Slow eruption and lava oozes  Examples: Mauna Loa in Hawaii and Mount Wrangell in Alaska  Composite:  Tall, steep, symmetrical (explosive, hard to predict  Examples: Mount Hood in Oregon, Mount St. Helens in Washington (many of these all over the world

22. …  Cinder Cone  Lava in the form of cinders  Most common type  Examples: Mount Mazama in Oregon (Crater Lake)  Hot Spot: magma emerges from Earth but not at plate boundaries (middle of plates)  Examples: Hawaiian Islands, Galapagos, Iceland, Yellowstone

23. Effects of Volcanoes  Release of CO 2, CO, He, H 2, HF (poisonous), SO 2 (acid rain, pollution), HCl (irritant, acid rain)  Ozone depletion, global warming, haze effect (smog)  Not long term but combined with human activities they can be