Assertion: caldera's formation | /r/CapableOf | accumulate rain
Facets:
value: to form huge lakes
type: PURPOSE
value: gradually
type: MANNER
Source sentences:
text: Powerful volcanic eruptions from stratovolcanoes, spewing out huge volumes of volcanic rocks, lava, and ash in what are known as "plinian eruptions", often result in the formation of large volcanic caldera that gradually accumulates rain and snow to form huge lakes.