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seismic waves

vibrations that travel through the earth during an earthquake


a force pressing on an area


the layer of rock that forms Earth's outer surface


hot solid material between Earth's crust and core


the uppermost layer made up of the mantle and crust


the soft layer of mantle on which the lithosphere floats

outer core

a layer of molten and iron and nickel that surrounds the inner core

inner core

a dense ball of solid metal

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