Magma is created when rock in the Earth's lower crust and upper mantle melts.

岩浆是在地球下地壳和上地幔的岩石融化时产生的。

The Anatomy of a Volcano A volcano is essentially an opening in Earth's crust that allows magma-- molten rock from the mantle and lower crust-- to reach the surface.

火山的解剖结构 火山本质上是地壳中的一个开口，它允许岩浆（来自地幔和下地壳的熔岩）到达地表。