"Eruptions at Fuego have become more mafic with ... from Acatenango is something you don't just see—you feel it. The ground trembles beneath your feet, a deep roar cuts through the silence ...
An erupting Hawaii volcano once again began shooting fountains of lava that reached hundreds of feet high on Tuesday.
In this case, the ground was an erupting volcano. All of this leads to a very unstable condition, where the heated up air is less dense and lighter than the cooler air in the sky above the volcano ...