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Published byClaude Gray Modified over 9 years ago
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Key Question: How are volcanoes and earthquakes possibly linked to plate boundaries?
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Learning Objective: To be able to explain how the different types of plate boundaries create volcanoes and earthquakes.
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Starter BINGO! Eyes down for your first clue...
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Plate BoundaryDiagramDescriptionExample Constructive divergent plate boundaries Constructive plate boundaries occur when two plates move away from each other. North American and Eurasian Plate Destructive (subduction zones) plate boundaries Destructive plate boundaries occur when an oceanic plate is forced under (or subducts) a continental plate. Pacific Plate and the Eurasian Plate Conservative (transform faults) plate boundaries Conservative plate boundaries occur when two plates slide past each other. North American Plate and the Pacific Plate Collision plate boundaries Collision plate boundaries occur when two continental plates move towards each other. Indo-Australian and the Eurasian Plate
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Plate boundaries
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Constructive Plate Boundary At a constructive plate boundary, two plates move apart. As the two plates move apart, magma rises up to fill the gap. This causes volcanoes at this type of boundary. However, since the magma can escape easily at the surface the volcano does not erupt with much force. Earthquakes are also found at constructive boundaries. An example of a constructive boundary is the Mid-Atlantic Ridge.
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Constructive plate boundary
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Sea Floor Spreading! Did you know that the ocean floor in the Atlantic is growing by 3cm per year? Which of the following pairs of continents are moving further away from each other? 1)Europe and Africa 2)Europe and North America 3)South America and North America Mid-Atlantic ridge
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6 metres 36 metres928 metres200 metres The plates move at different rates. The Nazca and Pacific plates are moving apart at a rate of 18cm per year while the Eurasian and North American plates are moving apart at a rate of 3cm per year. To the nearest metre, how far will the Nazca and Pacific plates have moved over the next 200 years? How fast do plates move?
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A destructive plate boundary is found where a continental plate meets an oceanic plate. The oceanic plate descends under the continental plate because it is denser. As the plate descends it starts to melt due to the friction caused by the movement between the plates. This melted plate is now hot, liquid rock (magma). The magma rises through the gaps in the continental plate. If it reaches the surface, the liquid rock forms a volcano. Destructive Plate Boundary
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Collision boundaries occur when 2 plates of similar densities move together (i.e. a continental plate and a continental plate). This causes the material between them to buckle and rise up, forming fold mountains. The Himalayas are an example of a chain of fold mountains. They have been formed by the African plate colliding into the Eurasian plate. Collision Boundary
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Conservative plate boundaries exist where two plates do not directly collide but slide past each other along a fault (weakness). No volcanoes are found along these plate boundaries, but earthquakes do occur. An example of such a boundary is the San Andreas Fault in California. Conservative Boundary
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Your task is in pairs, to demonstrate the 4 types of plate boundaries using different coloured plasticine to show the movement of the plates. Then one pair moves on to hear another group’s descriptions of their sculptures. Once you have seen 2 or 3 sculptures please vote for the best one.
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Plenary The winning pair will now show their sculpture. Homework: find out the World’s 5 most recent volcanic eruptions and earthquakes. When? Where? How? Why? Produce detailed paragraphs on each.
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