Lots More Information Prev Next Related HowStuffWorks Articles How Earthquakes WorkHow Volcanoes WorkHow Bearings WorkHow Smart Structures Will WorkHow Hurricanes WorkHow Floods WorkHow Tornadoes Work More Great Links UC Berkeley Seismological LaboratoryHow Are Earthquake Magnitudes Measured?Build Your Own SeismographMake your own seismogram! Sources U.S. Geological Survey. "FAQ - Historic Earthquakes and Earthquake Statistics." 2008. (Aug. 28, 2008)http://earthquake.usgs.gov/learning/faq.php?categoryID=11&faqID=64 Up Next What conditions are required for life? Could you dig a hole all the way to the Earth’s mantle? How the Living Earth Simulator Will Work How Famine Works What is gravity?