Home » Geologic Hazards
Earthquakes - Learn about earthquakes and how they have affected cities and people.
Homeowners Insurance and Geologic Hazards Most policies do not cover geologic hazards.
Landslides A USGS fact sheet about landslides and events that trigger them.
Volcanoes Articles about volcanoes, volcanic hazards and eruptions past and present.
Largest Hurricanes Are they determined by wind speed, value of damage, most deaths?
Geology Tools - Hammers, field bags, hand lenses, maps, hardness picks, gold pans.
Rock Fall Photos
Yosemite Rock Fall Photos A photo sequence of a rockfall and debris avalanche by Herb Dunn.
What Causes a Tsunami? Learn how plate motions trigger earthquakes and tsunamis.
Liquefaction occurs when water-saturated soil is severely shaken and loses strength.
Volcanic Explosivity Rating volcanic eruptions based upon the volume of tephra ejected.
Expansive Soil Causes more damage than floods, hurricanes & tornadoes combined.
Most Powerful Eruption of the 20th Century - and most people have never heard of it.
Asteroid Impact Craters! Zoom in on 50 of Earth\'s largest impact craters.
Hurricane Names How are hurricanes named? Is your name on the list?
Abandoned Mines accidents take 20 to 30 lives per year. Many could be prevented.
Largest Tsunami - The wave with the highest run-up was in Lituya Bay, Alaska.
World Record Lightning - This lake has more lightning than any other place in the world.
Storm Surge can be the most damaging and deadly aspect of a hurricane.
Lightning Strikes Map
Lightning Strikes Map - shows the worldwide distribution of lightning activity.
San Andreas Map
Google Map of the San Andreas - Zoom in to see the fault trace plotted atop of a map.
Atlantic Tsunamis Rare events that can cause damage and threaten millions of people.
Pacific Tsunamis This ocean is surrounded by plate boundaries, that can produce tsunami.
Indian Ocean Tsunamis
Indian Ocean Tsunamis Deadly tsunamis triggered by earthquakes and volcanoes.
Yosemite Rockfall Hazards have been mapped by the National Park Service.