Assertion: caldera | /r/CapableOf | cover surrounding area
Facets:
value: in volcanic ash
type: LOCATION
Source sentences:
text: The caldera was created by a massive eruption about 3100 years ago that generated about 5 cubic kilometres (6.54 billion cubic yards) of pyroclastic flow and covered the surrounding area in volcanic ash up to 20 cm (8 inches) deep.