Lots More Information Related HowStuffWorks Articles Hawaii and Haleakala VolcanoesCrater Lake National Park: What To Know Before You GoHow Mars WorksHow does a seismograph work? What is the Richter Scale?How Fireworks WorkHow Hurricanes WorkHow Tornadoes WorkHow the Sun WorksWhat is dynamite and how does it work? More Great Links United States Geologic Survey's main page on VolcanoesIn-depth site on Volcanoes, from San Diego State University in CaliforniaVolcanoes OnlineVolcanoliveMichigan Technological University Volcano PageVolcano World