Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Science Ch. 6 and 7 Study Guide 1. What kind of damage can volcanic ash cause? Volcanic ash can contaminate the water supply, bury plants and animals, cause structural damage, and mix with water and form lahar. 2. What is a pyroclastic flow? A rapidly moving mixture of hot gases and solids 3. What is a fracture surface along which rocks can slip called? A fault 4. Elastic strain directly causes ___________________. Earthquakes 5. What is lahar and why is it dangerous? It is a rapidly moving mixture (made up of volcanic ash and water) that can travel downhill up to 10 meters per second. It can bury human and wildlife habitats. 6. Describe a cinder cone volcano. It is steep-sided, composed of basaltic lava, and develops from layers of tephra. 7. Where do most earthquakes occur? On or near Earth’s plate boundaries. 8. Describe a shield volcano. Gradual slopes, and built out of layers of gently flowing basaltic lava. 9. If the magma of a volcano has a high amount of dissolved gas in the magma (such as water vapor, carbon dioxide, sulfur dioxide, and hydrogen sulfide) then the volcano is more likely to erupt ________________________. Explosively 10. There are volcanoes on _______________________. the Hawaiian Islands because They are near a hot spot. 11. Know the drawings on page 253. 12. True or false. A surface wave travels fastest. (If false, which kind of wave does travel the fastest? False. A P wave travels fastest. 13. Which type of wave cannot travel through liquids (but can travel through solids)? Secondary waves 14. Why does magma form in the rifts when tectonic plates separate? Because the magma rises to fill the space between the separating tectonic plates through fissure eruptions. 15. Define the term “vent”. The central, circular, or oval-shaped opening of a volcano from which magma erupts 16. When a seismograph that is far away from an epicenter records an earthquake, the P waves would arrive (earlier/later) than the S-waves. (earlier) 17. Where do island arc volcanoes form? Where two oceanic plates converge 18. Why are there so many volcanoes near the Ring of Fire? There are tectonic plate boundaries at many locations near the Ring of Fire. 19. Where are most volcanoes located? Along plate boundaries 20. Why does magma rise toward the surface of the Earth? It is less dense and more buoyant than surrounding rock. 21. Which type of seismic wave travels fastest through rock? P waves. 22. Which type of seismic wave causes the most damage? Surface wave 23. What is a seismograph? An instrument used to record seismic waves/magnitude of earthquakes. 24. What is an epicenter? The point on the Earth’s surface directly above the earthquake’s focus. 25. What is a tsunami? A seismic sea wave 26. True or false. At least three seismograph recordings are needed to locate the epicenter of an earthquake. True. 27. How much stronger is an earthquake with a magnitude of 3.0 than an earthquake with a 2.0 magnitude? About 30 times stronger 28. What is the Moment Magnitude Scale based on? The amount of energy released during an earthquake 29. What is lava? Magma that rises to Earth’s surface 30. Name the most common hazard that can occur after an earthquake. Fires caused by ruptured gas or electrical lines 31. What is liquefaction? The process by which shaking during an earthquake causes loose sediment to act more like a liquid. 32. Where do volcanic arcs often form? Where an oceanic plate subducts beneath a continental plate 33. Know the following in order: 1. As tectonic plates move, rocks have tension forces acting on them. 2. The rocks stretch and bend 3. The rocks stretch beyond their elastic limit 4. The rocks snap, releasing energy. 34. Be familiar with the seismogram records on the top of pages 262 and 263. Be able to identify the arrival time differences of P-waves and S-waves. (Know which are P-waves and which are S-waves. 35. Know this chart: Plate Motion Prominent Fault Type Transform Convergent Divergent Strike – slip fault Reverse fault Normal fault Earthquake Characteristics Moderate, strong, shallow Strong, deep Weak and shallow