@waterhopper- There are maps available that tell you where all of the Seismic Hazard Zones are. If you live anywhere close to these areas, there should be maps posted in your local county building.
In addition, if you are looking to buy a home in a Seismic Hazard Zone, the Natural Hazards Disclosure Act of 1998 requires that property owners or real estate agents let you know. They must provide you with what is called a “Natural Hazard Disclosure Statement”. This is required when the property is within one or more state-mapped hazard areas.