Deep yellow, orange and purple colors at the western horizon. (Photo: Tom Pfeiffer)
More on VolcanoDiscovery
Small spherical balls of volcanic ash that form from a wet nucleus falling through a volcanic ash cloud.
Glossary of geologic terms
: A growing list of often illustrated explanations and definitions of geological terms and keywords, with focus on volcanology and seismology.
: Lists and maps of earthquakes in the world in near real time. Country lists, earthquake archive, and I-felt-it reports.