noun. A large crater formed by volcanic explosion or by collapse of a volcanic cone.

noun. A large kettle or caldron; hence, in geology, an amphitheatrical depression in a volcanic formation.

noun. A large crater formed by a volcanic explosion or by collapse of the cone of a volcano.

noun. a large crater caused by the violent explosion of a volcano that collapses into a depression

"I believe it has its own atmosphere because it is built in what you call a caldera, but I may have picked that information up from like a Syfy TV movie about the Coming Global Superstorm, or invented it in my own mind."

crater  volcanic crater  

Berra  Canberra  Cara  Chimera  Clara  

air-hole  crystallites  dozer  ejecta  emigrations