This KS3 Geography quiz will challenge you about earthquakes and volcanoes. From time to time, you may hear about earthquakes and volcanoes in the news. When they occur, they can sometimes be very destructive and people may be killed. In Britain, there are several earthquakes every year, but most are so small that hardly anyone notices them. We don't have any active or dormant volcanoes, ours are all extinct. The reason that we don't have big earthquakes and volcanoes is that we are not at a plate boundary.
The Earth is made from several different layers - the core, the mantle and the crust. The crust is the thinnest of the three layers and is cracked into large areas called plates. In some places the plates move apart. Molten material comes up as volcanoes from the hot inside of the Earth, filling up the gap as the plates move apart. In other places, one plate is pushed under another plate, down into the Earth. This movement is not smooth and each sudden movement is felt as an earthquake. The pushed-down plate also melts and the molten rock comes to the surface as a volcano. In some places the plates move sideways past each other. This movement is not smooth and again, the sudden movements are felt as earthquakes.
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You can find more about this topic by visiting BBC Bitesize - Disasters and responses
These are the inner core, the outer core, the mantle and the crust
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Although 'thin' it can be between 5 and 60+ km thick. That's a lot of km, but it is thin when compared with the rest of the thickness of the Earth
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It's called lava only if it flows out of a volcano
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The most common scale for measuring the strength of an earthquake is the Richter scale
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A vent usually appears at the surface as a crater if the volcano is still active. You can still see craters in extinct volcanoes if they haven't been eroded too much
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These move in different directions at the speed of a fingernail growing
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It isn't in an unstable part of the Earth's crust because it is not near to a plate boundary
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The name dormant suggests that it's 'sleeping'
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The last British volcanoes were active over 30 million years ago
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Approximately 90% iron, 10% nickel
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