Name: ______________________ Period: ________ Plate Tectonics, Earthquakes & Volcanoes Study Guide Find the answers to the following questions in your Note-taking Worksheet and in Chapter 7 (pgs 182-199) and Chapter 8 (pgs 210-231) in your textbook. 1. Name the theory that states continents have moved slowly to their current locations. Continental Drift 2. Who proposed the theory from question 1? Alfred Wegener 3. List 5 different pieces of evidence supporting the theory from question 1. Rock formations Plants in different climates Glacial deposits Animal fossils Puzzle like shape 4. The continents were once believed to be one large landmass called ___Pangaea____. 5. How did scientists discover a system of underwater mountain ranges? Echolocation; sound waves 6. Who was the scientist who discovered the mid-ocean ridge? Harry Hess 7. What evidence supports seafloor spreading? Magnetic field Youngest rocks at mid ocean ridge 8. What part of the earth’s layers make up the plates? Crust and upper mantle 9. The layers of earth from question 7 make up the __lithosphere_______. 10. The plastic-like layer below the lithosphere is called the ___asthenosphere________. 11. List the 3 different plate boundaries and describe how they move. Convergent – move towards each other Divergent – move away from each other Transform – slide past one another Name: ______________________ Period: ________ 12. List 5 different features caused by plate tectonics. Mountains Islands Rift valleys Volcanoes Earthquakes Deep sea trenches mid ocean ridge 13. Define the following key terms: Focus-origin of earthquake under ground Epicenter-point on earth’s surface above origin Tsunami-ocean wave caused by earthquakes Subduction Zone-area where one plate slides under another Sea-floor spreading – theory that the sea floor is spreading apart at the mid ocean ridge Convection currents – cycle of rising heat and sinking cool that causes the plates to move Hot spots – large bodies of magma that are pushed toward surface. 14. What instrument do scientists use to measure an earthquake’s vibrations? – seismograph 15. Earthquakes produce ___seismic________ waves. 16. Name the scale used to measure an earthquakes size. Richter Scale 17. Define the following key terms: Volcano-cone shaped mountain that erupts Magma-molten rock that is below the Earth’s surface Lava-molten rock that is on the Earth’s surface Pyroclastic Flow-cloud of dust, rock and hot gases that erupt from a volcano Name: ______________________ Period: ________ 18. List 3 types of volcanoes and describe the shape, composition and type of eruption for each. Shield volcano – gentle eruptions, gently sloping sides Composite volcano – steep sides, combination of eruptions, layered with tephra and rock Cinder-Cone volcano – steep sides, violent eruptions