Magma siphon

A magma siphon is a large machine placed over a source of lava (such as a volcano) to drain, store, and facilitate the safe transport of lava and other geological ejecta. It is primarily used to prevent the dangers of lava flows and eruptions, especially in urban areas. The collected material is shipped elsewhere, often by cargo haulers, but larger magma siphons can feature cannons that fire the material into orbit for faster collection.