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2010 1. How Do Earthquakes Occur?

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2010 1. How Do Earthquakes Occur? CE Earthquake Review- 2010 1. How do earthquakes occur? They occur by tectonic plates moving past each other. 2. What are the three different plate boundaries? Transform, convergent, divergent. 3. What are some effects of earthquakes? Mountains can be formed, volcanoes can be formed, and trenches can be formed. 4. What is a convergent plate boundary? When two plates collide. 5. What is a divergent plate boundary? When two plates separate. 6. What is a transform plate boundary? When two plates slide past each other. 7. How are mountains formed? It’s created by a convergent plate boundary. 8. What are the layers of the earth? Crust, mantle, outer core, and inner core. 9. How did the scientists know Pangaea existed? Fossils, rocks, climate, and the fit of the continents. 10. How do scientists know about the layers of the earth? Earthquakes waves travel to seismograph stations through the inner earth. 11. What causes convection currents? Uneven heating 12. What causes earthquakes? Convection currents in the earth’s mantle move tectonic plates and build up pressure that is suddenly released, causing earthquakes. 13. What is the difference between an S-wave and a P-wave? P-wave is faster (Push and Pull), S-wave is slower (Side to Side) 14. What causes a rift valley? A divergent plate boundary spreading apart and filling with magma. 15. What is a subduction zone? A convergent plate boundary where one plate is pushed under another. 16. What is the inner core made of and how do we know? Iron and nickel because the earth has a magnetic field. 17. What is the focus of an earthquake? The place underground where an earthquake occurs. Directly below the epicenter. 18. What is an epicenter? The exact location of an earthquake at the surface, above the focus. 19. Explain what happens when two continental plates converge and what landform is created. When two thick continental plates converge the ground is forced up and mountains are formed. One example is the Himalayan Mountain Range. 20. How was Mt. Everest created? By a convergent plate boundary with two continental plates. They collide together, and then, move upward. 21. What was the name of the super continent 200 million years ago? Pangea! 22. What is magnitude? Magnitude is the strength and intensity of an earthquake. 23. What is the Richter scale? It measures the magnitude and energy of an earthquake. 24. What does the mantle have to do with tectonic plate movement? The convection currents in the mantle move the plates. 25. What are the differences between P-waves and S-waves? P-waves: push and pull, primary, faster, and weaker. S-waves: side to side, secondary, slower, stronger. 26. How do you measure earthquake waves? By using a seismograph, which is a tool that measures earthquake waves. 27. What is the Lithosphere? The crust and rigid mantle. 28. What is the Asthenosphere? It is the “taffy” like part of the mantle. 29. Who created the Theory of Plate Tectonics? Alfred Wegner created the theory of plate tectonics; he believed that al the continents were once a supercontinent called Pangaea he had four main pieces of evidence to prove that climate evidence, fossil evidence, continent evidence,(the way they fit together) and plant evidence. 30. How do you find the epicenter of an earthquake? With triangulation. Triangulation is using three points to pinpoint a location. 31. What is the process that moves heat through the mantle? Convection 32. What is the magnitude of an earthquake? The measure of how much energy an earthquake releases. 33. What is the intensity of an earthquake? The measure of the amount of damage done by an earthquake. 34. What happens when two oceanic plates collide? The older, colder, denser plate moves deep into earth creating a trench, or deep valley. 35. What happens when oceanic and continental plates collide? The oceanic plate will dive into the ground and create a subduction zone. 36. What happens when two plates slide past each other? A transform boundary creates a fault line. 37. What are the two types of crust and how are they different? Oceanic crust is thin and dense. Continental crust is thick, warmer, and less dense than oceanic. 38. Which layer of the earth is taffy-like? The mantle is made of molten rock and moves like a thick liquid. 39. Give three pieces of evidence that support the existence of a supercontinent. A. Fit, or shape of the continents. B. Fossil records of same fossils on different continents. C. Rock records indicate continental boundaries used to be connected. 40. What is a seismologist? A scientist who studies earthquakes. 41. Which Chinese astronomer invented the first earthquake detector? Chang Heng 42. Where are earthquakes most likely to happen? Where 2 Tectonic Plates meet 43. What causes earthquakes? Two Tectonic Plates colliding 44. What was the magnitude of the Alaskan earthquake in 1964? 9.2 45. How high does the Richter scale go up every whole number? 10 times 46. What is the definition of Frictional Resistance? The build up of friction in rocks (stored energy). 47. What is the name of the process of finding the epicenter of an earthquake? Triangulation 48. What layer of the earth can earthquakes not travel through? The Inner Core 49. What is the definition of the lithosphere? The outer shell of the earth that consist of the crust and the outer most part of the mantle 50. What are the 4 pieces of evidence that support the continental drift theory? Fit, Fossils, Climate, and Rock 51. Who is Charles Richter? A scientist who invented the Richter scale to measure the Magnitude and Intensity of Earthquakes. 52. What is the difference between a Seismograph and a Seismogram? A Seismograph is a tool that records the seismic activity; A Seismogram is the paper that prints out of a seismograph. 53. What is the best material to build a house on for an Earthquake? Loose Sand, Compact Soil, or Bed Rock? Bed Rock would be the best material to build a house on for on Earthquake. 54. What is the Epicenter of an Earthquake? The Epicenter of an Earthquake is surface location above the focus. 55. Name three different plate boundaries? The Mid Atlantic Ridge, Ring of Fire, and San Andreas Fault. 56. What evidence supports the Theory of Plate Tectonics? Continental Fit, Fossil Evidence, Climatic Evidence, Rock and mineral. 57. What are all the Layers of the Earth? Crust, Mantle, Outer Core, Inner Core. 58. What are S-Waves and P-Waves? P-Waves are (Push, Pull) earthquakes and they are the Primary Earthquakes that come first, and do Low Damage, S-Waves are (Side to side) earthquakes that come Secondary and finishes off the damage the P-Waves do. 59. What is Triangulation? The recording of the EQ data from three different places, then you calculate how much time it took to get there. 60. What causes Earthquakes? Two Tectonic plates Colliding or Sliding past one another. 61. The movements of the tectonic plates is caused by? Uneven heating on the earth’s surface causes convection currents in the mantle. 62. Describe the mantle. It’s a plastic like liquid that is like taffy it has convection currents called convection cells that move the tectonic plates. 63. Who made the first earthquake detector? Chang hang. 64. How do scientists know what the inside of the earth looks like? Scientists use the data from seismograms and knowledge about how s-waves and p-waves travel. They also use the “shadow effect” and existence of the earth’s magnetic field. 65. Why do earthquakes happen along fault lines? The tectonic plates are sliding past each other and building FRICTIONAL RESISTANCE. This resistance stores energy until the earthquake release. 66. How do Earthquakes occur? Earthquakes happen when the tectonic plates crash into each other. 67. How are earthquakes related to volcanoes? They both shake the earth 68. What are seismographs? they record the vibrations of earthquakes 69. What’s a Richter scale? 1-10 movement scale x10 for earth quakes 70. What is an epicenter? The surface location above the focus where the earthquake starts 71. What is Divergent? When two plates separate 72. What is an aftershock? seismic waves after an earthquake 73. What is frictional resistance? The build up of friction between rocks in tectonic plates (stored energy). 74. What is convergent? Where plates collide 75. What is the true center of an earthquake? The focus. 76. What is the Mid Atlantic Ridge? It is a zone of intense earthquake and volcanic activity in the middle of the Atlantic Ocean floor. 77. What is the difference between brittle and ductile? Brittle is something that breaks or cracks easily. Ductile is something that stretches or bends easily. 78. What is a fault? A Fault is a fracture in bedrock, along which blocks of rock on opposite sides of the fracture move. 79. What is the asthenosphere? The layer of the mantle that lies directly below the lithosphere and flows, like taffy. 80. What are the layers inside the earth? The inner core, outer core, mantle, and the crust. 81. What is an aftershock? An earthquake wave that follows the main shock of an earthquake. 82. What is the focus? The location where the rupture of an earthquake begins and energy is released. 83. What is Magnitude? A measure of the total amount of energy released at the source of an earthquake. 84. What is a Plate? A large, mobile segment of the earth’s Lithosphere. 85. What is a seismograph? An instrument that detects records and measures the vibrations produced by an earthquake.
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