Assertion: volcano's magma | /r/HasProperty | rich
Facets:
value: in silica
type: LOCATION
value: in gas
type: OTHER
Source sentences:
text: In contrast, magma that is rich in gas and silica gives rise to violent explosions: the thick, tarlike magma may plug up the volcanic vent, blocking the upward movement of the magma until built-up pressure blows away the overlying rock.