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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 in San Andreas.
The moviemakers consulted Thomas 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 hit Japan, 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 major tectonic 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 Francisco in 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 Tejon in 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. The latest 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 the ShakeOut 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 seismologist Lucy 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 current drought—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 in San Andreas could 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 can prepare for what will come. Jones spent most of 2014 working with the LA mayor's office to identify vulnerabilities and better prepare the city for the inevitable. The task force reported that 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 many obstacles—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 in ShakeOut 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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FAQs
What will happen in the future with the San Andreas fault? ›
Even so, in all probability, the San Andreas is likely to generate a significant earthquake in the not too distant future. When it arrives, the damage will be significant and southern California will be massively affected.
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 would happen if San Andreas happen? ›Narrator: Parts of the San Andreas Fault intersect with 39 gas and oil pipelines. This could rupture high-pressure gas lines, releasing gas into the air and igniting potentially deadly explosions. Stewart: So, if you have natural-gas lines that rupture, that's how you can get fire and explosions.
What is the Big One and what will happen if it occur? ›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.
What year will the Big One hit? ›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. Two earthquakes have previously been data-classified as big ones; The San Francisco quake in 1906 with a magnitude of 7.8 and the Fort Tejon quake in 1857 that hit 7.9.
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.
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 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.
Will there be a tsunami if the San Andreas fault? ›The San Andreas fault cannot create a big tsunami, as depicted in the movie.
Is California going to break off? ›No, California is not going to fall into the ocean. California is firmly planted on the top of the earth's crust in a location where it spans two tectonic plates.
How will the Big One affect San Diego? ›
SAN DIEGO — What would happen if a massive earthquake hit San Diego? If a 6.9 magnitude quake happened along the Rose Canyon Fault, which mirrors the path the I-5 freeway takes from La Jolla to Downtown, it could cause an estimated $38 billion of damage with up to 800 deaths.
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.
How can you survive if the big one earthquake strike? ›Cover your head and neck with your arms. If a sturdy table or desk is nearby, crawl underneath it for shelter. If no shelter is nearby, crawl next to an interior wall (away from windows). Crawl only if you can reach better cover without going through an area with more debris.
How will you prepare for the big one? ›Before the disaster, we must prepare and plan. It is better to learn Basic Life Support & First Aid and survival skills/mountaineering basics. We must also have an emergency plan and a list of important emergency service numbers. One of the things that we must check is the sturdiness of our house/building.
What to do when the big one hits? ›- If you are in a building, stay there. ...
- “Drop, cover and roll” is still a good guideline: Drop to the floor, cover your face and tuck your body into a ball.
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.
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.
Is San Andreas overdue for an earthquake? ›A study by the U.S. Geological Survey indicates that a portion of the San Andreas fault near Tejon Pass could be overdue for a major earthquake. Earthquakes occur about every hundred years on average, along this section of the fault, with the last major earthquake occurring in 1857: the magnitude 7.9 Fort Tejon quake.
Is the San Andreas fault gonna rupture? ›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.
What does Lawrence say will happen when the 9.5 earthquake comes? ›"The earth will literally crack and you will feel it on the east coast." "I hope we've given everyone enough warning."
How far does the San Andreas Fault extend? ›
The San Andreas is the "master" fault of an intricate fault network that cuts through rocks of the California coastal region. The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth.
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.
What is the truth about the San Andreas Fault? ›The San Andreas Fault is a continental transform fault that extends roughly 1300 km (810 miles) through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip (horizontal).
Will there ever be a 9.9 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.
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.
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.
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.
How do you prepare for the San Andreas Fault? ›...
- Have an emergency kit, including a by-the-bed kit and a commute kit. ...
- Know your neighbors. ...
- Protect your home, inside and out. ...
- Make a family plan.
Yes, tsunamis can happen in California. Although tsunamis aren't incredibly common across the state, California's long coastline makes it vulnerable to them, particularly because of the state's location along the Pacific Rim.
What will California's population be in 2030? ›•
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.
How would California be split? ›
Six Californias would have divided the state's 58 counties among six new states: Jefferson (based on the historic State of Jefferson proposal), North California, Silicon Valley, Central California, West California, and South California.
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 |
75% chance one or more M7. 0 or greater earthquakes will strike Southern California. 76% chance one or more M7. 0 or greater earthquakes will strike Northern California.
Will California pull away after a massive earthquake and drift into the middle of the Pacific ocean becoming its own island? ›Despite rumors that a large earthquake will cause California to break off into the ocean, there is no need to worry. This is impossible to occur from an event on the San Andreas fault, due to its fault type.
How close is San Diego to an active fault? ›Most people in San Diego live 15 miles from a fault. Be prepared.
How likely is San Andreas to happen? ›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.
What is the chance of a m6 7 earthquake in California in the next 30 years? ›Los Angeles area:
Within the next 30 years the probability is: 60% that an earthquake measuring magnitude 6.7.
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 are the chances of a big earthquake hitting the San Andreas fault in the next 30 years? ›In areas near the state boundary, it is nearly 100 percent likely to occur. In the San Francisco and Los Angeles regions, the USGS estimates that there is a 10 percent chance of a strong magnitude 6.7 earthquake in the next 30 years.
What would happen if there was a major earthquake at San Andreas fault? ›Narrator: Parts of the San Andreas Fault intersect with 39 gas and oil pipelines. This could rupture high-pressure gas lines, releasing gas into the air and igniting potentially deadly explosions. Stewart: So, if you have natural-gas lines that rupture, that's how you can get fire and explosions.
What happens if the San Andreas fault moves? ›
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.
What is the chance of the big one happening? ›Geological surveys say there is a 30 per cent chance of Los Angeles witnessing a 7.5-magnitude earthquake in the next 30 years.
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 will happen to San Francisco when the Big One hits? ›SAN FRANCISCO, CA — The "big one," a powerful earthquake that could devastate California at any moment, will likely kill thousands of people and topple buildings, crumble bridges and roads, sever water lines and ignite numerous fires.
Where is the Big One most likely to hit? ›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.
Will there be a big earthquake in California? ›The threat of earthquakes extends across the entire San Francisco Bay region, and a major quake is likely before 2032. Knowing this will help people make informed decisions as they continue to prepare for future quakes.
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.
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!
Should I worry about the San Andreas Fault? ›The San Andreas Fault is one of the main FAQs people have about visiting California. While the fault line is a matter of concern and planning for those living there, it shouldn't be a worry for anyone wanting to discover this incredibly stunning state.
Will San Andreas Fault cause a tsunami? ›Tsunami Science
The San Andreas fault cannot create a big tsunami, as depicted in the movie.
What will happen to the San Andreas Fault in 20 million years? ›
Assuming the plate boundary does not change as hypothesized, projected motion indicates that the landmass west of the San Andreas Fault, including Los Angeles, will eventually slide past San Francisco, then continue northwestward toward the Aleutian Trench, over a period of perhaps twenty million years.
What cities will be affected by the San Andreas earthquake? ›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 parts of California are most at risk do to the San Andreas fault? ›The greater San Francisco Bay Area has a high likelihood of future damaging earthquakes as it straddles the San Andreas fault system—the major geologic boundary between the North American and Pacific tectonic plates.
What cities are next to San Andreas fault? ›The San Andreas runs deep near and under some of California's most populated areas. The cities of Desert Hot Springs, San Bernardino, Wrightwood, Palmdale, Gorman, Frazier Park, Daly City, Point Reyes Station and Bodega Bay rest on the San Andreas fault line.
How far down does the San Andreas Fault go? ›The San Andreas is the "master" fault of an intricate fault network that cuts through rocks of the California coastal region. The entire San Andreas fault system is more than 800 miles long and extends to depths of at least 10 miles within the Earth.
What fault line is worse than San Andreas? ›Cascadia more fearsome than San Andreas
Truth is, the San Andreas is a lightweight compared with the Cascadia. The Cascadia can deliver a quake that's many times stronger – plus a tsunami.
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.
What tectonic plate most of the state of California will be part of in approximately 5 or 10 million years if the plate motion continues in the same way? ›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 will happen to the land west of the San Andreas Fault over time? ›With continued displacement, all land areas west of the San Andreas Fault, including Baja California and the city of Los Angeles, will be displaced northward along the California coast. As Baja California is displaced northward, the Gulf of California will, over time, widen to become part of the open Pacific Ocean.