What is Earth's mantle?
The layer of the Earth under the crust.
The Earth is made up of four main layers, the crust, the mantle, the outer core, and the inner core.
The mantle is the layer directly below the crust and is made up of mostly solid rocks, but magma as well. The mantle tends to be more liquidy at tectonic plate boundaries, which can cause magma to spill out to the surface as lava.
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