Assertion: volcano's crater | /r/MadeOf | small lava lakes
Facets:
value: often
type: TEMPORAL
Source sentences:
text: Its most active craters often contain small lava lakes.
text: Often, both Marum and Benbow (as well as other craters) contain small lava lakes, which occasionally erupt lava flows onto the caldera floor, or even exit the caldera through erosion gaps.