The science behind earthquakes
A collection of research and insights from Stanford experts on where and how earthquakes happen, why prediction remains elusive, advances in detection and monitoring, links to human activities, how to prepare for "The Big One," and more.
October 26, 2020
The ground beneath our feet is always in motion. In an earthquake, it can roll, shudder and crack as rocky puzzle pieces in Earth’s outer layer lurch past one another. Forces that accumulate miles underground over centuries or longer can deliver a catastrophic burst of energy in a matter of seconds.
Most quakes are small. As many as 500,000 detectable earthquakes occur each year. Nearly 100,000 of them are strong enough to be felt, and only about 100 cause damage. They usually occur in the upper 10 miles or so of the Earth’s crust, and they’re concentrated along the boundaries where tectonic plates meet.
Over the past two decades, however, earthquakes have caused more than half of all deaths related to natural disasters. In any given quake, the extent of harm depends heavily on the population density and building designs in the place where it strikes. And worldwide, the human cost of these events falls overwhelmingly on the poor. One study found that even when property damages are roughly equal, measures of well-being decline more steeply in cities that have lower-income population and lower household savings. In another study, which followed children whose mothers experienced a major earthquake during pregnancy, researchers showed that exposure to this kind of acute stress in utero can have negative effects years later among children in poor households.
Although predicting when a particular fault will unleash a quake remains out of reach, scientists have uncovered much of how, where and why earthquakes occur. This collection covers how scientists are deciphering the physics of earthquakes, developing technology to study them, discovering how quakes evolve and more.
Scroll down for earthquake research news and insights related to detection and monitoring, how earthquakes happen, human dimensions including strategies for resilience and connections to energy development, and prediction and preparedness.
Last updated: October 26, 2020
AI detects hidden earthquakes
Tiny movements in Earth’s outermost layer may provide a Rosetta Stone for deciphering the physics and warning signs of big quakes. New algorithms that work a little like human vision are now detecting these long-hidden microquakes in the growing mountain of seismic data.
What can machine learning tell us about the solid Earth?
Scientists are training machine learning algorithms to help shed light on earthquake hazards, volcanic eruptions, groundwater flow and longstanding mysteries about what goes on beneath the Earth’s surface.
Small quakes at fracking sites may warn of bigger tremors to come
Stanford geoscientists have devised a new algorithm for detecting thousands of faint, previously missed earthquakes triggered by hydraulic fracturing, or “fracking.”
Building a ‘billion sensors’ earthquake observatory with optical fibers
Stanford geophysicist Biondo Biondi dreams of turning existing networks of buried optical fibers into an inexpensive “billion sensors” observatory for continuously monitoring and studying earthquakes
Harnessing fiber-optic networks to map earthquake trouble spots
A study provides new evidence that the same optical fibers that deliver high-speed internet and HD video to our homes could one day provide an inexpensive observatory for monitoring and studying earthquakes.
'Shazam for earthquakes'
An algorithm inspired by the song-matching app is helping Stanford scientists find previously overlooked earthquakes in large databases of ground motion measurements.
Seismic map of North America reveals earthquake hazards
New research provides the first quantitative synthesis of faulting across the entire continent, as well as hundreds of measurements of the direction from which the greatest pressure occurs in the Earth’s crust.
2015 Nepal earthquake offers clues about hazards
Stanford geophysicist Simon Klemperer discusses how the 2015 Gorkha earthquake that shook Kathmandu in central Nepal gave researchers new information about where, why and how earthquakes occur
How earthquake swarms arise
A new fault simulator maps out how interactions between pressure, friction and fluids rising through a fault zone can lead to slow-motion quakes and seismic swarms
Researchers explain earthquakes we can't feel
Scientists have explained mysterious slow-moving earthquakes known as slow slip events with the help of computer simulations. The answer, they learned, is in rocks’ pores
Deadly earthquake traveled at 'supersonic' speeds
An earthquake in Indonesia that cracked through the Earth at nearly 9,200 miles an hour offered a detailed look at supershear, which can create the geologic version of a sonic boom. Stanford geophysicist Eric Dunham told National Geographic the event could help researchers understand where and how super-fast quakes can happen.
How two big quakes triggered 16,000 more in Southern California
“We’d like to think we know about all of the faults of that size and their prehistory, but here we missed it,” Ross Stein, an adjunct professor in geophysics at Stanford, told The New York Times.
Feature | Stanford geophysicist visits Loma Prieta epicenter
Cities built to endure disaster
There are technologies available that could move us toward stronger, safer buildings, but a lack of political and economic will is holding us back. Stanford civil engineer Anne Kiremidjian says a culture of resilience can help cities bounce back from disaster stronger than ever.
The inequalities of prenatal stress
A study found that economically disadvantaged children prenatally exposed to an environmental stressor had much lower cognitive abilities than their counterparts who didn’t experience the stress. No effect was found among children in upper- or middle-class families. The study used a strong earthquake in Chile to explore the impacts.
Lessons from the disaster zone
A Stanford doctor discusses his experience providing emergency medical response to earthquakes in Nepal and Haiti, and explains what leaders should know before the next natural disaster strikes.
A more holistic way to measure the economic fallout from earthquakes
Officials know how to account for deaths, injuries and property damages after the shaking stops, but a new study describes the first way to estimate the far greater financial fallout that such a disaster would have, especially on the poor.
Quakes caused by humans, nature are not so different after all
Research shows that human-induced and naturally occurring earthquakes in the central U.S. share the same shaking potential and can thus cause similar damage.
Solving geothermal energy's earthquake problem
A geothermal energy project triggered a damaging earthquake in 2017 in South Korea. A new analysis suggests flaws in some of the most common ways of trying to minimize the risk of such quakes when harnessing the Earth’s heat for energy.
Media Mention | April 2018
Seismic upheaval through history
In the course of his research for a book about the collapse of civilizations following earthquake storms – devastating sequences of seismic upheaval – Stanford geophysicist Amos Nur found that historians often overlook ancient earthquakes because written documentation of their occurrence is rare.
“Yet the physical ruins left behind these events testify to the presence of catastrophic forces lurking in the landscape,” Wired reported. “Nur’s unsettling conclusion is that earthquake damage throughout human history has been substantially underestimated.”
Read the full story: "Move over, San Andreas: There's an ominous new fault in town."
Data helps us prepare for 'The Big One'
Data is reshaping our knowledge about many things, including earthquakes: how we measure them, what causes them and how we can better prepare for them.
Understanding aftershock risk
Geophysicist Gregory Beroza discusses the culprits behind destructive aftershocks and why scientists are harnessing artificial intelligence to gain new insights into earthquake risks.
Study casts doubt on predictive value of earthquake foreschocks
A study suggests foreshocks are just like other small quakes, not helpful warning signs as previously thought.
A new technique predicts how earthquakes would affect a city's hospitals
A Stanford-led research team is helping disaster response officials figure out where injuries are likeliest to occur, so survivors can get to the hospitals best able to treat them.
A risk assessment of San Francisco's fire-fighting water system
After the 1906 quake the city built a water network dedicated to fire-fighting. A computer model suggests the best strategy to strengthen this system for another century.
How will San Francisco's skyscrapers fare after the next Big One?
Stanford civil engineers are working with the city to assess high-rise safety and mitigate any disruption, downtime or lost economic activity should downtown buildings be damaged.
Research | Stanford scientists use ‘virtual earthquakes' to forecast Los Angeles quake risk
Q&A | October 2019
Reflecting on the Loma Prieta earthquake
On the anniversary of the 1989 Loma Prieta earthquake, experts shared their perspectives on how the event impacted them and the Bay Area, and transformed earthquake science.
“As soon as it had stopped, I went down the hall to an old analog phone – all the others were computer phones and dead – to call Dr. Rob Wesson, PhD ’70, who was the head of the earthquake office at the USGS,” said geophysics professor William Ellsworth, who was working as a research geophysicist at the U.S. Geological Survey in his Menlo Park office at the time of the quake. “He was excited to hear me and wanted to talk baseball, at least until I told him that we had just experienced a major earthquake and our lives would be different from now on. How true that proved to be.”
