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Tectonic Hazards Horizon Tectonic Hazards Horizon We are going to watch a clip from a BBC Two programme, Horizon, where we will learn about subduction zones and how they can trigger earthquakes. Task: as we watch, complete the True or False activity. If false, right the correct answer below in the space provided. True / False 1. The earth’s crust is made up large plates of rock, which remain stagnant (still) for thousands of years. ________________________________________________ True / False 2. At the point that two plates meet each other, one of the huge plates can get pushed down beneath the other. This is called a subduction zone. ________________________________________________ True / False 3. A subduction zone off the coast of Sumatra caused the devastating 2004 Boxing Day earthquake. ________________________________________________ True / False 4. The fault line off the coast of Sumatra was very unlike any other subduction zones across the world. ________________________________________________ True / False 5. Whilst there are subduction zones at different points around the Earth, mainly they occur around the rim of the Pacific Ocean. ________________________________________________ True / False 6. The Ring of Fire, is where the world’s most dangerous and destructive volcanoes occur. ________________________________________________ True / False 7. At subduction zones, the plate that is being pushed down can get stuck. As it keeps pushing, the upper plate gets squeezed and distorted. When the strain builds up to an excessive point, the upper-plate slips, creating a megathrust earthquake. ________________________________________________ Tectonic Hazards Horizon We are going to watch a clip from a BBC Two programme, Horizon, where we will learn about subduction zones and how they can trigger earthquakes. Answers 1. The earth’s crust is made up large plates of rock, which are constantly moving. 2. At the point that two plates meet each other, one of the huge plates can get pushed down beneath the other. This is called a subduction zone. 3. A subduction zone off the coast of Sumatra caused the devastating 2004 Boxing Day earthquake. 4. Across the world, there are many fault lines similar to the subduction zone off the coast of Sumatra. 5. Whilst there are subduction zones at different points around the Earth, mainly they occur around the rim of the Pacific Ocean. 6. The Ring of Fire, is where the world’s most dangerous and destructive earthquakes occur, around the rim of the Pacific Ocean 7. At subduction zones, the plate that is being pushed down can get stuck. As it keeps pushing, the upper plate gets squeezed and distorted. When the strain builds up to an excessive point, the upper-plate slips, creating a megathrust earthquake. .
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