The frequent eruptions helped to preserve fossils and evidence of animal life.
Ample rainforests have grown there, though they are often destroyed by frequent eruptions.
Llaima is one of Chile's most active volcanoes and has frequent but moderate eruptions.
These outbursts can be split into frequent eruptions and less frequent supereruptions.
In a study published online by the journal Science, the scientists say that Etna may be due for a period of frequent and powerful eruptions.
The pool also had frequent boiling eruptions on August 15, 1991, doming the water to 3 feet and causing heavy runoff.
These systems are characterised by frequent eruptions and less frequent supereruptions.
The area offered the opportunity to see lava running down the sides of the active volcano and hear its frequent small eruptions from a distance.
During this stage, the volcano builds height through increasingly frequent eruptions.
And in a crater 650 feet below that is the volcano, which produces frequent noisy eruptions.