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A giant earthquake will strike California this summer. Skyscrapers will topple, the Hoover Dam will crumble and a massive tsunami will wash across the Golden Gate Bridge. Or at least, that’s the scenario that will play out on the big screen inSan Andreas.
The moviemakers consultedThomas Jordan, director of the Southern California Earthquake Center, before they started filming, but “they probably didn’t take much of my advice,” he says. While the actual threats from the Big One are pretty terrifying, they are nowhere near the devastation witnessed by Dwayne "The Rock" Johnson and his onscreen companions. Even the largest of San Andreas' quakes can’t produce a massive tsunami like the one that swells over San Francisco in the movie. “The really big tsunamis, like the one that hitJapan, are caused by earthquakes that generate a major displacement of the ocean floor,” Jordan says. The San Andreas fault sits far inland, and the land slips past on either side. For that reason, a quake also can’t cause the fault to split apart into a giant chasm as it does in the film. And despite the warnings of distraught movie scientists, even the largest of California's quakes won’t be felt by anything but seismometers on the East Coast.
That doesn’t mean California is off the hook, though. While the movie may be more fantasy than reality, the Big One is coming, and it will produce plenty of destruction. “We think Southern California is locked and loaded, that the stresses have really built up, and when things start unleashing, they could unleash for years,” says U.S. Geological Survey seismologist Ned Field.
California sits at the border between two majortectonic plates—the Pacific plate, which is moving northwest, and the North American plate, which is sliding past it to the southeast. The two plates don’t just meet at a single line, and the state is crisscrossed with dozens of earthquake faults. The San Andreas is the most worrisome, because it generates the quakes that are really dangerous to California residents, Jordan notes.
The northern San Andreas leveled San Franciscoin 1906, but it’s been a lot longer since the southern part of the fault ruptured. On average, Southern California has seen big quakes every 110 to 140 years, based on records of past earthquakes and studies of earthquake faults. The last big quake near Los Angeles, a magnitude 7.9, struck Fort Tejonin 1857. Farther south, near Palm Springs, the fault hasn’t ruptured in over 300 years. “Eventually the fault will have to break,” Jordan says.
While seismologists can’t predict exactly when that will happen, every few years they release a forecast for the likelihood of such an event. Thelatest forecast, published earlier this year by the USGS, estimates a 7 percent chance that a magnitude 8 quake will occur in California within the next 30 years. That’s about as big as earthquakes can get in California, notes Jordan—a magnitude 8.3 quake might be possible if the entire San Andreas fault were to rupture from the Mexico border up to northern California. “We don’t think that’s likely,” he says.
To figure out what could realistically happen when the Big One finally strikes, a team of earthquake experts sat down sat down several years ago and created theShakeOut scenario. Seismologists modeled how the ground would shake and then other experts, including engineers and social scientists, used that information to estimate the resulting damage and impacts. The detailed report examines the effects of a hypothetical 7.8 quake that strikes the Coachella Valley at 10 a.m. on November 13, 2008. In the following minutes, the earthquake waves travel across California, leveling older buildings, disrupting roads and severing electric, telephone and water lines.
But the quake is only the beginning.
Hundreds of fires start, and with roads blocked and the water system damaged, emergency personnel aren’t be able to put them all out. Smaller fires merge into larger ones, taking out whole sections of Los Angeles. The lines that bring water, electricity and gas to Los Angeles all cross the San Andreas fault—they break during the quake and won’t be fixed for months. Though most modern buildings survive the shaking, many are rendered structurally unusable. Aftershocks shake the state in the following days, continuing the destruction.
The scenario is actually somewhat of an underestimate, notes one scientist behind the ShakeOut, USGS seismologistLucy Jones. The report’s team was surprised by the extent of the fire damage from the quake, Jones says, but it could be worse if the Santa Ana winds are blowing when the event happens. These seasonal winds blow dusty, dry air from inland toward the coast, increasing risks of wildfires. And while Los Angeles keeps a supply of water on its side of the San Andreas, the reservoirs have been drained by the currentdrought—if the quake struck today, water reserves wouldn't last the maximum of six months that they would when full, she notes.
Overall, such a quake would cause some $200 billion in damage, 50,000 injuries and 2,000 deaths, the researchers estimated. But “it’s not so much about dying in the earthquake. It’s about being miserable after the earthquake and people giving up on Southern California,” says Jones. Everything a city relies on to function—water, electricity, sewage systems, telecommunications, roads—would be damaged and possibly not repaired for more than a year. Without functioning infrastructure, the local economy could easily collapse, and people would abandon Los Angeles.
“Imagine America without Los Angeles,” Jones posits. While the fictional disaster inSan Andreascould be an additional wake-up call for Californians, Jones worries that its unrealistic scenario could lead people to believe that there’s nothing to worry about or nothing they can do about it. Moviegoers may think that scientists will be able to give them fair warning of the Big One, even though earthquake prediction is currently an impossibility.
But Californians canpreparefor what will come. Jones spentmost of 2014working with the LA mayor's office to identify vulnerabilities and better prepare the city for the inevitable. Thetask force reportedthat building codes could be changed to require retrofitting of older structures so that they would withstand powerful shaking. The Los Angeles aqueduct could be fortified so that it won’t break when the San Andreas ruptures. Power, telecommunications and internet systems could be strengthened or have backup systems to ensure that people would be able to communicate. The plan would take billions of dollars and several decades to implement—and would have to overcome manyobstacles—but it would improve the city’s ability to survive a quake catastrophe.
On an individual level, homeowners can retrofit their property to better hold up against shaking. People can include fire extinguishers in their earthquake kits to put out little flames before they get out of hand. And schools, businesses and families can participate inShakeOut drills—the next one is on October 15—to practice what they’ll need to do on earthquake day.
“Everyone should live every day like it could be the day of the Big One,” says Field. Because any day, even today, could be that day.
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What Will Really Happen When San Andreas Unleashes the Big One? ›
The biggest the predicted earthquake would be is around an 8.3 magnitude, which would be colossally destructive, ripping a path from the tip of California right down to Mexico, according to Smithsonian Magazine. In this worst-case scenario, the entire San Andreas faultline would be impacted.
What will happen after the San Andreas fault? ›According to the U.S. Geological Survey, it is highly likely that some areas across the fault will experience a magnitude 6.7 earthquake in the next 30 years. In areas near the state boundary, it is nearly 100 percent likely to occur.
What will happen to Los Angeles when the Big One hits? ›Stewart: You might start seeing key industries leave, population loss, and this could have, you know, devastating long-term impacts for the region. Narrator: The estimated financial cost of the big one is a whopping $200 billion, with $33 billion in building damages and $50 billion in lost economic activity.
What happens if the San Andreas fault opens? ›Scientist project the San Andreas fault line could cause a devastating earthquake in California by 2030. This fault has caused some of the biggest earthquakes in California with a magnitude. Most of California's population lives and works on the west side of the fault. Do you live near the San Andreas fault?
What will happen when the Big One hits? ›The 'Big One' is a hypothetical earthquake of magnitude ~8 or greater that is expected to happen along the SAF. Such a quake will produce devastation to human civilization within about 50-100 miles of the SAF quake zone, especially in urban areas like Palm Springs, Los Angeles and San Francisco.
How likely is the big one? ›We know the San Andreas Fault will strike again and significantly impact all civilization within a 50-100 mile radius. According to USGS there is a 70% chance that one or more quakes of a magnitude 6.7 or larger will occur before the year 2030.
How overdue is California for a big earthquake? ›Probabilities (shown in boxes) of one or more major (M>=6.7) earthquakes on faults in the San Francisco Bay Region during the coming 30 years. The threat of earthquakes extends across the entire San Francisco Bay region, and a major quake is likely before 2032.
How soon will the big one happen? ›The "Big One," a massive earthquake predicted to hit California along the San Andreas Fault, is expected to occur sometime in the next 100 years, and experts warn that climate change could make the already deadly event even worse.
What cities would be affected by the San Andreas fault? ›| San Andreas Fault | |
|---|---|
| Cities | San Francisco, San Bernardino, San Juan Bautista |
| Characteristics | |
| Segments | Calaveras, Hayward, Elsinore, Imperial, Laguna Salada, San Jacinto |
| Length | 1,200 km (750 mi) |
"The earth will literally crack and you will feel it on the east coast." "I hope we've given everyone enough warning."
Is California going to break off? ›
The strike-slip earthquakes on the San Andreas Fault are a result of this plate motion. The plates are moving horizontally past one another, so California is not going to fall into the ocean. However, in about 12 million years, Los Angeles and San Francisco will be adjacent to one another!
Could the whole San Andreas fault go off? ›As such, recent predictions limit the possible maximum earthquake magnitude along the San Andreas fault system to 8.0, although with a 7% probability estimate that such an event could occur in Southern California in the next 30 years; over the same period, there is a 75% chance of a magnitude 7.0 event.
Will there be an earthquake in California in 2025? ›There wasn't a 6.8 magnitude earthquake Wednesday evening off the California coast. A U.S. Geological Survey alert reported around 4:50 p.m. that the big earthquake hit Isla Vista at 7:42 a.m. on June 29, 2025. The initial alert alarmed people, but a closer look at the alert revealed the very odd date and time.
Will the Big One cause tsunami? ›"The big issue is it's going to actually move up in that vertical motion underneath the ocean. That results in a tsunami," Warning Coordination Meteorologist Ryan Aylward said. This zone has experienced multiple large-scale earthquakes and tsunamis over the past 10,000 years, the last of them occurring in 1700.
Can a 9.0 earthquake happen in California? ›The Cascadia Subduction Zone stretches underneath the Humboldt-Del Norte county region, extending from Cape Mendocino all the way up through the Pacific Northwest. This fault zone is capable of generating a magnitude 9 (or larger) earthquake on average every 500 years.
What will the Big One do to Seattle? ›SEATTLE – A future major earthquake centered under Seattle's Puget Sound could trigger a tsunami that would bury the waterfronts under 20 feet of water for hours, according to a new study released Thursday by the Washington State Department of Natural Resources.
How long will the San Andreas earthquake last? ›The U.S. Geological Survey calculated those quakes as having “violent” shaking, or an intensity of 9 on a 10-point scale. A big San Andreas quake, The Times has reported, would bring “extreme” shaking: 10 out of 10. And it could last for nearly two minutes, according to the USGS.
Are there little earthquakes before a big one? ›A foreshock is an earthquake that occurs before a larger seismic event (the mainshock) and is related to it in both time and space.
Will the San Andreas fault hit Los Angeles? ›The strike-slip earthquakes on the San Andreas Fault are a result of this plate motion. There is nowhere for California to fall, however, Los Angeles and San Francisco will one day be adjacent to one another! Learn more: Earthquakes, Megaquakes, and the Movies.
Can California have a 10.0 earthquake? ›No, earthquakes of magnitude 10 or larger cannot happen. The magnitude of an earthquake is related to the length of the fault on which it occurs.
When could the next large earthquake occur along the San Andreas fault? ›
Seismic activity along the San Andreas fault line could trigger a devastating earthquake in California by 2030.
How do you survive the big one? ›During an earthquake, get under a table or desk. Hold on until shaking stops. Pick safe places in each room of your home. Create an emergency survival kit that provides you and your pets with three days of nonperishable food and water, medicines, emergency radio and first aid materials.
How deep is the San Andreas Fault? ›The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth. In detail, the fault is a complex zone of crushed and broken rock from a few hundred feet to a mile wide.
How do you know if a big earthquake is coming? ›Neither the USGS nor any other scientists have ever predicted a major earthquake. We do not know how, and we do not expect to know how any time in the foreseeable future.
What are 3 states in the US that have a high earthquake risk? ›California has more earthquakes that cause damage than any other state. Alaska and California have the most earthquakes (not human-induced).
What states will feel the San Andreas Fault? ›The San Andreas Fault location begins in Northern California, south of Cape Mendocino. It moves southeast going through major cities such as Santa Rosa, San Francisco, Desert Hot Springs, San Jose, and winds down to San Bernardino outside of Los Angeles and the Salton Sea.
Which 6 states are most at risk for these earthquakes? ›Tsunami Science
The San Andreas fault cannot create a big tsunami, as depicted in the movie.
The most important is water: drinking, boiling for food preparation, washing, wound cleansing, etc. Next comes survival gear: dried or dehydrated food, pots for boiling water, clothing, shelter (tents and sleeping bags), rain gear, medicine, battery or solar powered radio, etc.
Is a 13.0 earthquake possible? ›So, let's come back to the question: The magnitude of an earthquake is related to the length of the fault. The problem of a magnitude 13 is, that it is not possible according to this concept due to the earth's physical limitations. Keep in mind, that with one magnitude higher, a quake has about 32 times more energy.
When was the last big earthquake in California? ›
| Magnitude | Date | Damage |
|---|---|---|
| 7.1 | Nov. 4, 1927 | No major injuries; slight damage in 2 counties |
| 7.1 | Oct. 16, 1999 | Minimal damage due to remote location |
| 7.1 | July 5, 2019 | Preceded by M6.4 quake; no fatalities |
| 7.0 | May 18, 1940 | 9 killed; $6 million in damage |
•
By 2030, California's population is projected to reach 44.1 million. Annual growth rates are expected to be just under 1 percent, similar to growth experienced in the first decade of this century.
notable faults in San Diego
San Diego, Los Angeles and Big Sur are on the Pacific Plate of the San Andreas fault. San Francisco, Sacramento and the Sierra Nevada are on the North American Plate. This sliding boundary between the plates is what causes major earthquakes. San Diego has three active faults.
The earthquake of May 22, 1960, that struck the town of Valdivia in southern Chile is the most powerful ever recorded and has become known as the Great Chilean Earthquake. It is thought to have measured 9.5 on the moment magnitude scale (MMS).
When was the last big one on the San Andreas fault? ›The last “big one”-level movements in California's recorded earthquake history are the 1857 earthquake in the central third of the San Andreas and the 1906 earthquake in the northern third.
Where will the San Andreas fault move? ›San Andreas Fault, major fracture of the Earth's crust in extreme western North America. The fault trends northwestward for more than 800 miles (1,300 km) from the northern end of the Gulf of California through western California, U.S., passing seaward into the Pacific Ocean in the vicinity of San Francisco.
Will the 1906 earthquake happen again? ›So, while the most likely time for a 1906-like earthquake to strike again is perhaps late in the next century, there is a small chance (about 2 percent) that it could happen in the next 30 years.
What tectonic plate will California be on in the future? ›Eventually the Juan de Fuca plate will continue to disappear underneath the North American plate and the entire stretch of the west coast will be the Pacific Plate abutting against the North American Plate. This allows for the northward movement of western California along the coast until it reaches Alaska.
What to do when the big one hits? ›If you are in a building, stay there. Most of our buildings, including high rises, will do well in an earthquake, even if they sway. “Drop, cover and roll” is still a good guideline: Drop to the floor, cover your face and tuck your body into a ball.
What will be the cause of the big one? ›Experts monitoring seismic activity in the region are concerned that California could be due for a huge earthquake, known as the "Big One", due to large amounts of pressure built up between the static plates of the San Andreas fault. An earthquake of this scale is expected to occur around once every 100 to 220 years.
How long did the big one last? ›
| The Big One | |
|---|---|
| Speed | 74 mph (119 km/h) |
| Inversions | 0 |
| Duration | 3:00 |
| Max vertical angle | 65° |
The 'Big One' is a hypothetical earthquake of magnitude ~8 or greater that is expected to happen along the SAF. Such a quake will produce devastation to human civilization within about 50-100 miles of the SAF quake zone, especially in urban areas like Palm Springs, Los Angeles and San Francisco.
How far inland does a big tsunami go? ›Tsunami waves can continously flood or inundate low lying coastal areas for hours. Flooding can extend inland by 300 meters (~1000 feet) or more, covering large expanses of land with water and debris.
Will San Andreas trigger Yellowstone? ›No. A massive rupture along the San Andreas Fault zone might be felt in Yellowstone, but it will not have enough energy to cause a volcano to erupt that wasn't already poised to do so.
What cities will be affected by the San Andreas Fault? ›| San Andreas Fault | |
|---|---|
| Cities | San Francisco, San Bernardino, San Juan Bautista |
| Characteristics | |
| Segments | Calaveras, Hayward, Elsinore, Imperial, Laguna Salada, San Jacinto |
| Length | 1,200 km (750 mi) |
Now scientists are warning that those consequences could be even more severe next time. The "Big One," a massive earthquake predicted to hit California along the San Andreas Fault, is expected to occur sometime in the next 100 years, and experts warn that climate change could make the already deadly event even worse.
Will all of California be affected by the San Andreas fault? ›The strike-slip earthquakes on the San Andreas Fault are a result of this plate motion. There is nowhere for California to fall, however, Los Angeles and San Francisco will one day be adjacent to one another! Learn more: Earthquakes, Megaquakes, and the Movies.
What cities will be affected by the San Andreas fault? ›| San Andreas Fault | |
|---|---|
| Cities | San Francisco, San Bernardino, San Juan Bautista |
| Characteristics | |
| Segments | Calaveras, Hayward, Elsinore, Imperial, Laguna Salada, San Jacinto |
| Length | 1,200 km (750 mi) |
The San Andreas Fault location begins in Northern California, south of Cape Mendocino. It moves southeast going through major cities such as Santa Rosa, San Francisco, Desert Hot Springs, San Jose, and winds down to San Bernardino outside of Los Angeles and the Salton Sea.
What can trigger the San Andreas fault? ›The Pacific Plate (on the west) slides horizontally northwestward relative to the North American Plate (on the east), causing earthquakes along the San Andreas and associated faults.
What is the biggest fault line in the world? ›
The San Andreas fault line in California is the longest in the world. It sits between the Pacific and North American plates and measures 1300kms. The depths of these collision zones can range from 0-700km.
How close is the San Andreas fault to breaking? ›As such, recent predictions limit the possible maximum earthquake magnitude along the San Andreas fault system to 8.0, although with a 7% probability estimate that such an event could occur in Southern California in the next 30 years; over the same period, there is a 75% chance of a magnitude 7.0 event.
How far inland would a mega tsunami go? ›Waves of this type are called Mega Tsunami. They are so great that they can reach several hundred meters in height, travel at the speed of a jet aircraft and get up to 12 miles (20 Kilometers) inland. A mega-tsunami is an extremely rare and destructive phenomenon that strikes the world every few thousand years.
Will there be a big tsunami in California? ›There is No Tsunami Warning, Advisory, Watch, or Threat in effect. 85 Mi.
What would happen if a nuke was detonated in the San Andreas Fault? ›The shock waves would be contained and reflected between the walls of the trench likely triggering underwater rock slides. The bubble of water vapor would rise rapidly through the water column, likely breaking the surface as an enormous water and steam jet.
Is Yellowstone shrinking? ›Though they were tweaked by President Herbert Hoover, Yellowstone's original borders haven't changed all that much. But the wild natural habitat available in the Greater Yellowstone Ecosystem, an area ten times larger than the park itself, has been shrinking dramatically.
Is San Andreas supposed to be an island? ›San Andrés (Islander Creole English: San Andrés) is a coral island in the Caribbean Sea. Politically part of Colombia, and historically tied to the United Kingdom, San Andrés and the nearby islands of Providencia and Santa Catalina form the department of San Andrés, Providencia and Santa Catalina.