FAQs

If you are looking for faults in California use: How Close to a Fault Do You Live? (Bay Area Earthquake Alliance) For faults in California and the rest of the United States (as well as the latest earthquakes) use the Latest Earthquakes Map : click on the "Basemaps and Overlays" icon in the upper right corner of the map. check the box for "U.S. Faults". mouse-over each fault to get a pop-up window...

An online map of faults ( Quaternary Fault and Fold Database of the United States ) that includes California is in the Faults section of the Earthquake Hazards Program website. Choose the Interactive Fault Map, or download KML files and GIS shapefiles from the links on the page. USGS hazard maps, data, and tools for California and other parts of the United States are in the Seismic Hazard Maps and...

The Great Valley is a basin, initially forming ~100 million years ago as a low area between the subducting ocean plate on the west (diving down under the North American plate) and the volcanoes to the east (now the Sierra Nevada mountains). Since its formation, the Great Valley has continued to be low in elevation. Starting about 20 million years ago the tectonics changed in California and instead...

This region of the United States has been tectonically active since the supercontinent Pangea broke up roughly 200 million years ago, and in large part because it is close to the western boundary of the North American plate. Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North American plates has formed many faults in California...

Faults vs. Fault Lines on a Map In order to answer this question, we first need to explain some basics about faults. Faults are different from fault lines. A fault is a three-dimensional surface within the planet that might extend up to the surface or might be completely buried. In contrast, a fault line is where the fault cuts the Earth's surface… if indeed it does. The most prominent faults in...

Many faults are mapped as individual segments across an area. These fault segments are given a different value for name, number, code, or dip direction and so in the database each segment occurs as its own unique entity. For example, the San Andreas Fault has several fault segments, from letters a to h, and fault segment 1h has segments with age of last fault movement from historic (<150 years) to...

There are four basic steps you can take to be more prepared for an earthquake: Step 1: Secure your space by identifying hazards and securing moveable items. Step 2: Plan to be safe by creating a disaster plan and deciding how you will communicate in an emergency. Step 3: Organize disaster supplies in convenient locations. Step 4: Minimize financial hardship by organizing important documents...

Fire extinguisher Adequate supplies of medications that you or family members are taking Crescent and pipe wrenches to turn off gas and water supplies First-aid kit and handbook Flashlights with extra bulbs and batteries Portable radio with extra batteries Water for each family member for at least two weeks (allow at least 1 gallon per person per day) and purification tablets or chlorine bleach to...

If you are INDOORS -- STAY THERE! Get under a desk or table and hang on to it ( Drop, Cover, and Hold on! ) or move into a hallway or against an inside wall. STAY CLEAR of windows, fireplaces, and heavy furniture or appliances. GET OUT of the kitchen, which is a dangerous place (things can fall on you). DON'T run downstairs or rush outside while the building is shaking or while there is danger of...

DO NOT turn on the gas again if you turned it off; let the gas company do it DO NOT use matches, lighters, camp stoves or barbecues, electrical equipment, appliances UNTIL you are sure there are no gas leaks. They may create a spark that could ignite leaking gas and cause an explosion and fire DO NOT use your telephone, EXCEPT for a medical or fire emergency. You could tie up the lines needed for...

WEAR STURDY SHOES to avoid injury from broken glass and debris. Expect aftershocks CHECK FOR INJURIES If a person is bleeding, put direct pressure on the wound, use clean gauze or cloth if available If a person is not breathing administer CPR DO NOT attempt to move seriously injured persons unless they are in further danger of injury COVER injured persons with blankets to keep warm SEEK medical...

The contents of your home may be damaged and can be dangerous: Shaking can make light fixtures fall, refrigerators and other large items move across the floor, and bookcases and television sets topple over. IDENTIFY: Look around your house for things that could fall or move. Ask yourself if your cupboard doors could fly open (allowing dishes to shatter on the floor). Is TV and stereo fastened down...