Frequently Asked Questions


Can you predict earthquakes?

No. Neither the USGS nor any other scientists have ever predicted a major earthquake. They do not know how, and they do not expect to know how any time in the foreseeable future. However based on scientific data, probabilities can be calculated for potential future earthquakes. For example, scientists estimate that over the next 30 years the probability of a major EQ occurring in the San Francisco Bay area is 67% and 60% in Southern California.


Can animals predict earthquakes?

Changes in animal behaviour cannot be used to predict earthquakes. Even though there have been documented cases of unusual animal behaviour prior to earthquakes, a reproducible connection between a specific behaviour and the occurrence of an earthquake has not been made. Animals change their behaviour for many reasons and given that an earthquake can shake millions of people, it is likely that a few of their pets will, by chance, be acting strangely before an earthquake.


What is it about an earthquake that causes a tsunami?

Destructive local tsunamis are possible near the epicenter, and significant sea level changes and damage may occur in a broader region. Note that with a magnitude 9.0 earthquake, the probability of an aftershock with a magnitude exceeding 7.5 is not negligible.


What can I do to be prepared for a landslide?

Avoid building near steep slopes, close to mountain edges, near drainage ways, or natural erosion valleys. Get a ground assessment of your property. Learn about the emergency-response and evacuation plans for your area. Develop your own emergency plan for your family or business.