* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download File
Survey
Document related concepts
Axial Seamount wikipedia , lookup
Mount Garibaldi wikipedia , lookup
Mount Meager massif wikipedia , lookup
David A. Johnston wikipedia , lookup
Llullaillaco wikipedia , lookup
Mount Edziza volcanic complex wikipedia , lookup
Mount Pleasant Caldera wikipedia , lookup
Volcanology of Io wikipedia , lookup
Types of volcanic eruptions wikipedia , lookup
Mount Pinatubo wikipedia , lookup
Olympus Mons wikipedia , lookup
Mount St. Helens wikipedia , lookup
Cascade Volcanoes wikipedia , lookup
Mount Vesuvius wikipedia , lookup
Nevado del Ruiz wikipedia , lookup
Silverthrone Caldera wikipedia , lookup
Mount Pelée wikipedia , lookup
Cerro Azul (Chile volcano) wikipedia , lookup
Transcript
Volcanoes Activity Objective In this activity, we are going to explore the two main volcano types: shield and composite. We will understand their connection to plate tectonics and learn more about hazards associated with each volcano type. Part 1: Volcanoes & Volcano Types Go to http://nationalgeographic.org/encyclopedia/magma/ and look at the first 3 pictures 1. What is magma? 2. What is the difference between magma and lava? 3. Where is magma formed? 4. In which three locations does magma “well up”? Read P. 202-203 in your textbook and answer the following questions 5. Describe the shape of a shield volcano 6. What is its general eruption style? 7. Describe the shape of a composite volcano 8. What is its general eruption style? 9. Make a sketch of each volcano below Shield Composite Part 2: Where Are Volcanoes Located? 1. Look at the map given below. Are most of the world’s volcanoes located along a plate boundary? Yes No 2. Using your knowledge of plate tectonics (or the chart on P. 179), state whether or not the following plate boundary types have volcanoes: A. Divergent plate boundaries Yes No B. Continental-continental convergent plate boundaries Yes No C. Continental-oceanic convergent plate boundaries Yes No D. Oceanic-oceanic convergent plate boundaries Yes No E. Transform plate boundaries Yes No 3. Most volcanoes are at subduction boundaries, but subduction is not necessary to create a volcano. Which plate boundary has volcanoes but not subduction? ______________________________________________ 4. In this lab, we are focussing on shield and composite volcanoes, but lava does erupt at divergent plate boundaries as well. Visit http://www.geology.sdsu.edu/how_volcanoes_work/seafloorvol_page.html and answer the questions below A. What feature is created at divergent plate boundaries? (Circle one) Ridges Trenches B. How does that feature form? C. What type of eruption is usually seen at divergent boundaries? D. Are these violent or gentle eruptions? 5. There are clusters of volcanoes on the map not located near a plate boundary (ex. Hawaii). What are these volcanoes called? 6. Watch https://www.youtube.com/watch?v=jG-Sy0y08GM and explain how hot spots form. Part 3: Volcano Shape & Eruption Style Go to http://discoverykids.com/games/volcano-explorer/ to build your own volcano. Summarize what happens when you change the silica and gas concentrations in the magma and describe the type of volcano that forms, the type of eruption created and any hazards in the chart below Silica Content (high or low) Gas Content (high or low) High High High Low Low Low Low High Type of eruption (explosive, effusive, etc.) Hazards (list all shown) Type of Volcano 1. Which factor had more of an effect on the type of volcano formed: silica content or gas content? 2. Which conditions are required for the most explosive types of eruptions? 3. Watch https://www.youtube.com/watch?v=EGK1KkLjdQY and answer the following questions A. Name the three types of rock and briefly explain how each are formed: B. Which type would you expect to find at volcanoes? Why? C. Explain how sedimentary and metamorphic rocks could become igneous rocks 4. We are going to focus on 3 types of igneous rocks: felsic, intermediate and mafic (not ultramafic). Use the graph below to figure out which type has the most silica. The type with the most silica is called ________________________________ 5. Rocks with more silica are more viscous. What is viscosity? 6. Which is more viscous: water or molasses? _________________________________ 7. Watch this video of the eruption of Kilauea, the currently active volcano in Hawaii: https://www.youtube.com/watch?v=90XFpu-65JY A. Would you describe the lava as having high or low viscosity? ______________________________ B. What does this tell you about the silica content of this lava? 8. Watch this video of the eruption of Mt. St. Helens: https://www.youtube.com/watch?v=H_HZVY1tT4 A. Does the Mt. St. Helens eruption in 1980 seem to have a high or a low viscosity? ____________________ B. What does this tell you about the silica and gas content of the magma? 9. Do you think rocks with high silica content produce more explosive or less explosive eruptions? Why? 10. Would a violent eruption cause a tall and steep volcano or one with gentle slopes? 11. In general, continental crust is made up of more silica-rich rocks and oceanic crust is made up of mafic-rich rocks. How explosive do you think volcanoes at the following settings would be? A. Continental-oceanic convergence B. A hot spot underneath continental crust C. A hot spot underneath oceanic crust D. Diverging oceanic plates 12. Complete the table below: Composition Name Silica Content (high, intermediate or low?) Viscosity (high, intermediate or low?) Eruption (violent or gentle?) Crust type (oceanic or continental?) Felsic Intermediate Mafic Part 4: Exploring Volcanic Hazards Watch this video about pyroclastic flows: http://www.discovery.com/tv-shows/discoverypresents/videos/ultimate-guide-to-volcanoes-pyroclastic-flow/ 1. Is this hazard associated with more violent or gentle eruptions? 2. Does this type of hazard seem to have a high or low viscosity? 3. Would you expect to see felsic or mafic rocks? 4. At which type of volcano would you expect to see a pyroclastic flow, shield or composite? Watch this video about lava flows: http://www.discovery.com/tv-shows/discovery-presents/videos/understanding-volcanoes-lava-flow/ 5. Is this hazard associated with more violent or gentle eruptions? 6. Does this type of hazard seem to have a high or low viscosity? 7. Would you expect to see felsic or mafic rocks? 8. At which type of volcano would you expect to see a lava flow, shield or composite? *Note: lava flows are associated with both shield and composite volcanoes, but lava flows are the main hazard at shield volcanoes Watch this video about ash and the Mt. Pinatubo eruption: http://www.pbslearningmedia.org/resource/ess05.sci.ess.earthsys.lahar/mount-pinatubo-the-aftermathof-a-volcanic-eruption/ 9. Is this hazard associated with violent or gentle eruptions? 10. Which rock do they mention in the video as “raining down”? 11. Does this type of hazard seem to have high or low viscosity? 12. Would you expect to see felsic or mafic rocks? 13. At which type of volcano would you expect to see pyroclastic flows and huge volumes of ash: shield or composite? Explore this page and watch the video about lahars: http://blogs.agu.org/landslideblog/the-raw-power-ofthe-lahar-a-volcanic-landslide-a-new-video-of-three-lahars-from-japan/ 14. What is a lahar made of? 15. How fast can they travel? 16. Is this hazard associated with more violent or gentle eruptions? 17. Does this type of hazard seem to have a high or low viscosity? 18. Would you expect to see felsic or mafic rocks? 19. At which type of volcano would you expect to see lahars, shield or composite? 20. Out of all the hazards you’ve learned about, which hazards would you expect to see at Kilauea? 21. Out of all the hazards you’ve learned about, which hazards would you expect to see at Mt. Rainier? Part 5: Case Studies On the west coast of South America, the oceanic Nazca plate is colliding with the continental edge of the South American plate. Answer the following questions based on this information and what you have learned so far in this lab: 1. What type of plate boundary is this? 2. Would you expect to see subduction at this boundary? Yes No 3. Would you expect to see volcanoes at this boundary? Yes No Felsic Mafic 4. If so, what type of volcanoes? 5. Which igneous rocks would be present, felsic or mafic? 6. Would you expect a volcano in this location to have high or low viscosity? Why? 7. What hazards would you expect to see at this volcano? 8. Which of the two volcanoes below do you think you would find there? A B Yellowstone National Park is located in Wyoming, Idaho and Montana. Answer the following after reading http://www.yellowstonepark.com/how-the-yellowstone-calderaformed/ 9. Is Yellowstone located near a plate boundary? Yes No 10. What is the term for the location of a volcano that is not on a plate boundary? 11. The Yellowstone hotspot is located under: (circle one) Oceanic Crust Continental Crust 12. Therefore, the crust is: (circle one) Felsic Mafic 13. Yellowstone has had three major eruptions in the last 2 million years. The last eruption was 640,000 years ago and was 1,500 times larger than the one at Mt. St. Helens in 1980. What do you think would happen if another large eruption occurred again soon? At the very bottom of this website you will see a map showing the path of the Yellowstone hotspot. Use this map to answer the questions below https://volcanoes.usgs.gov/volcanoes/yellowstone/yellowstone_geo_hist_52.html 14. If the top of the map is north, where are the oldest volcanic eruptions from the Yellowstone hotspot? 15. Where are the youngest eruptions? 16. What does this tell you about the direction of plate motion of the North American plate? Part 6: Summary Fill out the table below Type of Volcano Shield Composite Plate Setting (hot spot or convergent) Crust Type (continental or oceanic) Magma Composition (felsic or mafic) Igneous Rocks Associated with Each Crust Type Types of Volcanic Hazards (lava flows, pyroclastic flows, lahars, ash fall, etc.)