Depiction of the Great Lisbon earthquake of 1755

Extremely large earthquakes, volcanic eruptions, magnetic storms, and other hazardous geophysical events are rare. And yet their occurrence can be devastating for humankind. Since direct historical records of extreme geophysical events are few, the interpretation of their statistics must be conducted with caution. Estimates of occurrence rates are useful, but the "error-bar" measures of uncertainty are also needed.

Examples of extreme-event work published by USGS scientists include:

Primary USGS contact: Jeffrey J. Love