Magma chambers under supervolcanoes are more like soggy sponges than reservoirs of molten rock. Before a volcano of this kind erupts, such mush must slowly be reactivated by heat input following deep magma recharge ultimately derived from the Earth’s mantle.

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Magma chambers under supervolcanoes are more like soggy sponges than reservoirs of molten rock. Before a volcano of this kind erupts, such mush must slowly be reactivated by heat input following deep magma recharge ultimately derived from the Earth’s mantle.