Assertion: volcano | /r/HasProperty | formed
Facets:
Source sentences:
text: Volcanoes are formed when magma from within the Earth's upper mantle works its way to the surface.
text: Hot seawater in hydrothermal vents does not boil because of the extreme pressure at the depths where the vents are formed.
text: When it does reach the surface, however, a volcano is formed.
text: A volcano is formed when liquid rock from deep underground bursts out through the hard outer surface of the Earth.
text: Volcanoes are formed when liquid rock from these magma chambers is pushed through the Earth’s crust.