Transcript Slide 1
• Have a seat with your lab group and get out your papers that you completed in class yesterday. • Today’s Schedule • 1. Review Yesterday’s Assignment • 2. Review for Ch. 7 Test ESSAY QUESTION • Explain what the theory of plate tectonics is, how it works, and how it is responsible for shaping the landforms on Earth’s surface. • 15 MC • 8 Short Answer • 1 Essay Inside the Earth • • • • • What does the inside of Earth look like? Layers How are the layers arranged? By density What happens to the temperature and pressure as you travel into the center of Earth? • Both Increase Inside the Earth • How do we know so much about Earth’s Interior? • Seismic waves from earthquakes • Seismic waves travel at different speeds and directions as they pass through the different layers of Earth. Restless Continents • • • • • • True or False: The continents are always moving? True What is this called? Continental drift Who created the theory of continental drift? Alfred Wegener Restless Continents • • • • What discovery helped prove Wegener’s theory? Mid-ocean ridges How did we discover mid-ocean ridges? Better Technology/sonar Restless Continents • What process happens at mid-ocean ridges to help move Earth’s plates? • Sea-floor Spreading The Theory of Plate Tectonics • The theory that Earth’s lithosphere are divided _______ that move around on top of the ______. • Plates, asthenosphere The Theory of Plate Tectonics • • • • What is the main cause of plate movement? Convection currents How do convection currents work? Core heats up molten rock making it less dense. The molten rock rises up towards the crust, where it cools down. As it cools it gets more dense and begins to sink back down through the mantle. This cycle will repeat over time, gradually moving Earth’s plates. • Flash Presentation The Theory of Plate Tectonics • • • • • • Two plates moving away from each other = ______ Divergent boundary Two oceanic plates are spreading apart =________ Mid-ocean Ridge/Sea-floor spreading Two continental plates diverging =________ Rift Valley • • • • • • The Theory of Plate Tectonics Two plates colliding with each other = _______ Convergent Boundary Two continental plates colliding = ________ Mountains Oceanic plate and Continental plate colliding=_____ Trenches, mountains, and volcanoes The Theory of Plate Tectonics • At convergent boundary between a continental plate and an oceanic plate what process will happen? • Subduction • Why? • The oceanic plate is more dense, so it goes under the continental plate. The Theory of Plate Tectonics • What type of boundary forms when two plates slip or slide past each other? • Transform Boundary • What disaster can be associated with transform boundaries? • Earthquakes