On Earth, sea-floor spreading is fuelled by molten rock upwelling from deep inside the Earth.

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Another well had to be abandoned when the drillers hit red-hot molten rock.

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It's a tin-can-shaped explosive covered with a lid of copper that turns into molten rock and pierces through armored vehicles.

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It says the flash of light comes not from any type of combustion -- as we typically think of explosions -- but rather by the glowing molten rock at the impact site.

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When the ocean plates sink deep enough, portions are melted by the intense heat generated within the mantle, turning the solid rock into molten magma.

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The heat that keeps the core of the earth molten is primarily radioactive decay -it is what makes rock into liquid lava.

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