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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. The San Andreas Fault System, which crosses California from the Salton Sea in the south to Cape Mendocino in the north, is the boundary between the Pacific Plate (that includes the Pacific Ocean) and North American Plate (that includes North America). These two plates are moving horizontally, slowly sliding past one another. The Pacific Plate is moving northwest with respect to the North American Plate at approximately 46 millimeters per year (the rate your fingernails grow). Thestrike-slipearthquakes 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:
Related Content
- FAQ
- Multimedia
- Publications
Can you predict earthquakes?
No. 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. USGS scientists can only calculate the probability that a significant earthquake will occur (shown on our hazard mapping) in a specific area within a certain number of years. An earthquake prediction must define 3 elements: 1...
No. 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. USGS scientists can only calculate the probability that a significant earthquake will occur (shown on our hazard mapping) in a specific area within a certain number of years. An earthquake prediction must define 3 elements: 1...
Can animals predict earthquakes?
The earliest reference we have to unusual animal behavior prior to a significant earthquake is from Greece in 373 BC. Rats, weasels, snakes, and centipedes reportedly left their homes and headed for safety several days before a destructive earthquake. Anecdotal evidence abounds of animals, fish, birds, reptiles, and insects exhibiting strange behavior anywhere from weeks to seconds before an...
The earliest reference we have to unusual animal behavior prior to a significant earthquake is from Greece in 373 BC. Rats, weasels, snakes, and centipedes reportedly left their homes and headed for safety several days before a destructive earthquake. Anecdotal evidence abounds of animals, fish, birds, reptiles, and insects exhibiting strange behavior anywhere from weeks to seconds before an...
Why are we having so many earthquakes? Has naturally occurring earthquake activity been increasing? Does this mean a big one is going to hit? OR We haven't had any earthquakes in a long time; does this mean that the pressure is building up for a big one?
A temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates. Neither an increase nor decrease worldwide is a positive indication that a large earthquake is imminent. The ComCat earthquake catalog contains an increasing number of earthquakes in recent years--not because there are more earthquakes, but because there are more seismic instruments and they are...
Why are we having so many earthquakes? Has naturally occurring earthquake activity been increasing? Does this mean a big one is going to hit? OR We haven't had any earthquakes in a long time; does this mean that the pressure is building up for a big one?
A temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates. Neither an increase nor decrease worldwide is a positive indication that a large earthquake is imminent. The ComCat earthquake catalog contains an increasing number of earthquakes in recent years--not because there are more earthquakes, but because there are more seismic instruments and they are...
Can "MegaQuakes" really happen? Like a magnitude 10 or larger?
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. That is, the longer the fault, the larger the earthquake. A fault is a break in the rocks that make up the Earth's crust, along which rocks on either side have moved past each other. No fault long enough to generate a magnitude 10 earthquake is known to...
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. That is, the longer the fault, the larger the earthquake. A fault is a break in the rocks that make up the Earth's crust, along which rocks on either side have moved past each other. No fault long enough to generate a magnitude 10 earthquake is known to...
Can some people sense that an earthquake is about to happen (earthquake sensitives)?
There is no scientific explanation for the symptoms some people claim to have preceding an earthquake, and more often than not there is no earthquake following the symptoms.
There is no scientific explanation for the symptoms some people claim to have preceding an earthquake, and more often than not there is no earthquake following the symptoms.
Can the ground open up during an earthquake?
Shallow crevasses can form during earthquake-induced landslides, lateral spreads, or from other types of ground failures, but faults do not open up during an earthquake. An earthquake occurs when two blocks of the earth’s crust slide past one another after having been stuck together in one place for a long time, because of friction on the fault, while the rest of the crust away from the edges has...
Shallow crevasses can form during earthquake-induced landslides, lateral spreads, or from other types of ground failures, but faults do not open up during an earthquake. An earthquake occurs when two blocks of the earth’s crust slide past one another after having been stuck together in one place for a long time, because of friction on the fault, while the rest of the crust away from the edges has...
Is there earthquake weather?
In the 4th Century B.C., Aristotle proposed that earthquakes were caused by winds trapped in subterranean caves. Small tremors were thought to have been caused by air pushing on the cavern roofs, and large ones by the air breaking the surface. This theory lead to a belief in earthquake weather, that because a large amount of air was trapped underground, the weather would be hot and calm before an...
In the 4th Century B.C., Aristotle proposed that earthquakes were caused by winds trapped in subterranean caves. Small tremors were thought to have been caused by air pushing on the cavern roofs, and large ones by the air breaking the surface. This theory lead to a belief in earthquake weather, that because a large amount of air was trapped underground, the weather would be hot and calm before an...
Do solar flares or magnetic storms (space weather) cause earthquakes?
Solar flares and magnetic storms belong to a set of phenomena known collectively as "space weather". Technological systems and the activities of modern civilization can be affected by changing space-weather conditions. However, it has never been demonstrated that there is a causal relationship between space weather and earthquakes. Indeed, over the course of the Sun's 11-year variable cycle, the...
Solar flares and magnetic storms belong to a set of phenomena known collectively as "space weather". Technological systems and the activities of modern civilization can be affected by changing space-weather conditions. However, it has never been demonstrated that there is a causal relationship between space weather and earthquakes. Indeed, over the course of the Sun's 11-year variable cycle, the...
Are earthquakes associated with variations in the geomagnetic field?
Electromagnetic variations have been observed after earthquakes, but despite decades of work, there is no convincing evidence of electromagnetic precursors to earthquakes. It is worth acknowledging that geophysicists would actually love to demonstrate the reality of such precursors, especially if they could be used for reliably predicting earthquakes! Learn more: USGS Geomagnetism Program
Electromagnetic variations have been observed after earthquakes, but despite decades of work, there is no convincing evidence of electromagnetic precursors to earthquakes. It is worth acknowledging that geophysicists would actually love to demonstrate the reality of such precursors, especially if they could be used for reliably predicting earthquakes! Learn more: USGS Geomagnetism Program
Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California
A new fault map of the shelf offshore of San Francisco, California shows that faulting occurs as a distributed shear zone that involves many fault strands with the principal displacement taken up by the San Andreas fault and the eastern strand of the San Gregorio fault zone. Structures associated with the offshore faulting show compressive deformation near where the San Andreas fault goes offshore
Authors
H. F. Ryan, T. Parsons, R. W. Sliter
Where's the San Andreas fault? A guidebook to tracing the fault on public lands in the San Francisco Bay region
No abstract available.
Authors
Philip W. Stoffer
Putting down roots in earthquake country: Your handbook for the San Francisco Bay region
This handbook provides information about the threat posed by earthquakes in the San Francisco Bay region and explains how you can prepare for, survive, and recover from these inevitable events. If you live or work in the region, you need to know why you should be concerned with earthquakes, what you can expect during and after a quake, and what you need to do beforehand to be safe and reduce damag
Authors
The USGS Earthquake Hazards Program - investing in a safer future
No abstract available.
Authors
John R. Filson, Jill McCarthy, William L. Ellsworth, Mary Lou Zoback, Peter H. Stauffer, James W. Hendley
ANSS-Advanced National Seismic System
No abstract available.
Authors
Harley M. Benz, John Filson, Walter Arabasz, Lind Gee, Lisa Wald
USGS National Seismic Hazard Maps
The U.S. Geological Survey (USGS) recently completed new probabilistic seismic hazard maps for the United States, including Alaska and Hawaii. These hazard maps form the basis of the probabilistic component of the design maps used in the 1997 edition of theNEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, prepared by the Building Seismic Safety Council a
Authors
A. D. Frankel, C.S. Mueller, T.P. Barnhard, E. V. Leyendecker, R. L. Wesson, S. C. Harmsen, F. W. Klein, D. M. Perkins, N.C. Dickman, S.L. Hanson, M. G. Hopper
Forecasting California’s earthquakes
The first official earthquake forecast for California emphasizes the broad extent of the hazard and the uncertainties involved in predicting the next quakes.For the first time, researchers have reached to a consensus on the threat of large earthquakes to California, things look no worse for Los Angles than before. It still has about a 60 percent chance of being shaken by a large earthquake someti
Authors
R. A. Kerr
Zoogeographic evidence for late Tertiary lateral slip on the San Andreas fault, California
No abstract available.
Authors
W. O. Addicott
Related Content
- FAQ
Can you predict earthquakes?
No. 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. USGS scientists can only calculate the probability that a significant earthquake will occur (shown on our hazard mapping) in a specific area within a certain number of years. An earthquake prediction must define 3 elements: 1...
No. 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. USGS scientists can only calculate the probability that a significant earthquake will occur (shown on our hazard mapping) in a specific area within a certain number of years. An earthquake prediction must define 3 elements: 1...
Can animals predict earthquakes?
The earliest reference we have to unusual animal behavior prior to a significant earthquake is from Greece in 373 BC. Rats, weasels, snakes, and centipedes reportedly left their homes and headed for safety several days before a destructive earthquake. Anecdotal evidence abounds of animals, fish, birds, reptiles, and insects exhibiting strange behavior anywhere from weeks to seconds before an...
The earliest reference we have to unusual animal behavior prior to a significant earthquake is from Greece in 373 BC. Rats, weasels, snakes, and centipedes reportedly left their homes and headed for safety several days before a destructive earthquake. Anecdotal evidence abounds of animals, fish, birds, reptiles, and insects exhibiting strange behavior anywhere from weeks to seconds before an...
Why are we having so many earthquakes? Has naturally occurring earthquake activity been increasing? Does this mean a big one is going to hit? OR We haven't had any earthquakes in a long time; does this mean that the pressure is building up for a big one?
A temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates. Neither an increase nor decrease worldwide is a positive indication that a large earthquake is imminent. The ComCat earthquake catalog contains an increasing number of earthquakes in recent years--not because there are more earthquakes, but because there are more seismic instruments and they are...
Why are we having so many earthquakes? Has naturally occurring earthquake activity been increasing? Does this mean a big one is going to hit? OR We haven't had any earthquakes in a long time; does this mean that the pressure is building up for a big one?
A temporary increase or decrease in seismicity is part of the normal fluctuation of earthquake rates. Neither an increase nor decrease worldwide is a positive indication that a large earthquake is imminent. The ComCat earthquake catalog contains an increasing number of earthquakes in recent years--not because there are more earthquakes, but because there are more seismic instruments and they are...
Can "MegaQuakes" really happen? Like a magnitude 10 or larger?
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. That is, the longer the fault, the larger the earthquake. A fault is a break in the rocks that make up the Earth's crust, along which rocks on either side have moved past each other. No fault long enough to generate a magnitude 10 earthquake is known to...
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. That is, the longer the fault, the larger the earthquake. A fault is a break in the rocks that make up the Earth's crust, along which rocks on either side have moved past each other. No fault long enough to generate a magnitude 10 earthquake is known to...
Can some people sense that an earthquake is about to happen (earthquake sensitives)?
There is no scientific explanation for the symptoms some people claim to have preceding an earthquake, and more often than not there is no earthquake following the symptoms.
There is no scientific explanation for the symptoms some people claim to have preceding an earthquake, and more often than not there is no earthquake following the symptoms.
Can the ground open up during an earthquake?
Shallow crevasses can form during earthquake-induced landslides, lateral spreads, or from other types of ground failures, but faults do not open up during an earthquake. An earthquake occurs when two blocks of the earth’s crust slide past one another after having been stuck together in one place for a long time, because of friction on the fault, while the rest of the crust away from the edges has...
Shallow crevasses can form during earthquake-induced landslides, lateral spreads, or from other types of ground failures, but faults do not open up during an earthquake. An earthquake occurs when two blocks of the earth’s crust slide past one another after having been stuck together in one place for a long time, because of friction on the fault, while the rest of the crust away from the edges has...
Is there earthquake weather?
In the 4th Century B.C., Aristotle proposed that earthquakes were caused by winds trapped in subterranean caves. Small tremors were thought to have been caused by air pushing on the cavern roofs, and large ones by the air breaking the surface. This theory lead to a belief in earthquake weather, that because a large amount of air was trapped underground, the weather would be hot and calm before an...
In the 4th Century B.C., Aristotle proposed that earthquakes were caused by winds trapped in subterranean caves. Small tremors were thought to have been caused by air pushing on the cavern roofs, and large ones by the air breaking the surface. This theory lead to a belief in earthquake weather, that because a large amount of air was trapped underground, the weather would be hot and calm before an...
Do solar flares or magnetic storms (space weather) cause earthquakes?
Solar flares and magnetic storms belong to a set of phenomena known collectively as "space weather". Technological systems and the activities of modern civilization can be affected by changing space-weather conditions. However, it has never been demonstrated that there is a causal relationship between space weather and earthquakes. Indeed, over the course of the Sun's 11-year variable cycle, the...
Solar flares and magnetic storms belong to a set of phenomena known collectively as "space weather". Technological systems and the activities of modern civilization can be affected by changing space-weather conditions. However, it has never been demonstrated that there is a causal relationship between space weather and earthquakes. Indeed, over the course of the Sun's 11-year variable cycle, the...
Are earthquakes associated with variations in the geomagnetic field?
Electromagnetic variations have been observed after earthquakes, but despite decades of work, there is no convincing evidence of electromagnetic precursors to earthquakes. It is worth acknowledging that geophysicists would actually love to demonstrate the reality of such precursors, especially if they could be used for reliably predicting earthquakes! Learn more: USGS Geomagnetism Program
Electromagnetic variations have been observed after earthquakes, but despite decades of work, there is no convincing evidence of electromagnetic precursors to earthquakes. It is worth acknowledging that geophysicists would actually love to demonstrate the reality of such precursors, especially if they could be used for reliably predicting earthquakes! Learn more: USGS Geomagnetism Program
- Multimedia
- Publications
Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California
A new fault map of the shelf offshore of San Francisco, California shows that faulting occurs as a distributed shear zone that involves many fault strands with the principal displacement taken up by the San Andreas fault and the eastern strand of the San Gregorio fault zone. Structures associated with the offshore faulting show compressive deformation near where the San Andreas fault goes offshore
Authors
H. F. Ryan, T. Parsons, R. W. Sliter
Where's the San Andreas fault? A guidebook to tracing the fault on public lands in the San Francisco Bay region
No abstract available.
Authors
Philip W. Stoffer
Putting down roots in earthquake country: Your handbook for the San Francisco Bay region
This handbook provides information about the threat posed by earthquakes in the San Francisco Bay region and explains how you can prepare for, survive, and recover from these inevitable events. If you live or work in the region, you need to know why you should be concerned with earthquakes, what you can expect during and after a quake, and what you need to do beforehand to be safe and reduce damag
Authors
The USGS Earthquake Hazards Program - investing in a safer future
No abstract available.
Authors
John R. Filson, Jill McCarthy, William L. Ellsworth, Mary Lou Zoback, Peter H. Stauffer, James W. Hendley
ANSS-Advanced National Seismic System
No abstract available.
Authors
Harley M. Benz, John Filson, Walter Arabasz, Lind Gee, Lisa Wald
USGS National Seismic Hazard Maps
The U.S. Geological Survey (USGS) recently completed new probabilistic seismic hazard maps for the United States, including Alaska and Hawaii. These hazard maps form the basis of the probabilistic component of the design maps used in the 1997 edition of theNEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, prepared by the Building Seismic Safety Council a
Authors
A. D. Frankel, C.S. Mueller, T.P. Barnhard, E. V. Leyendecker, R. L. Wesson, S. C. Harmsen, F. W. Klein, D. M. Perkins, N.C. Dickman, S.L. Hanson, M. G. Hopper
Forecasting California’s earthquakes
The first official earthquake forecast for California emphasizes the broad extent of the hazard and the uncertainties involved in predicting the next quakes.For the first time, researchers have reached to a consensus on the threat of large earthquakes to California, things look no worse for Los Angles than before. It still has about a 60 percent chance of being shaken by a large earthquake someti
Authors
R. A. Kerr
Zoogeographic evidence for late Tertiary lateral slip on the San Andreas fault, California
No abstract available.
Authors
W. O. Addicott
As an enthusiast with a deep understanding of seismic activity and geophysics, I'd like to shed light on the concepts mentioned in the provided article, showcasing my expertise in the field.
-
San Andreas Fault System:
- The article correctly highlights that California is not at risk of falling into the ocean. The San Andreas Fault System, stretching from the Salton Sea to Cape Mendocino, marks the boundary between the Pacific Plate and North American Plate. The horizontal movement of these plates, about 46 millimeters per year, results in strike-slip earthquakes along the fault.
-
Earthquake Prediction:
- The US Geological Survey (USGS) emphasizes that predicting earthquakes, especially major ones, remains a challenge. Instead, scientists calculate the probability of significant earthquakes occurring in specific areas over a certain period. The article rightly dismisses the notion of predicting earthquakes with certainty.
-
Animal Behavior and Earthquakes:
- The article mentions anecdotal evidence of animals exhibiting unusual behavior before earthquakes. While historical references exist, there is no scientific explanation for such behavior, and it is not a reliable predictor of earthquakes.
-
Earthquake Frequency:
- The article addresses the misconception about earthquake frequency, clarifying that temporary increases or decreases in seismic activity are part of normal fluctuations. The rise in recorded earthquakes is attributed to the increased deployment of seismic instruments, not necessarily a surge in actual seismic events.
-
Magnitude of Earthquakes:
- It is rightly explained that earthquakes of magnitude 10 or larger cannot occur. The magnitude is directly related to the length of the fault, and no fault has been identified as long enough to generate a magnitude 10 earthquake.
-
Earthquake Sensitivity:
- The article dismisses claims of some individuals sensing earthquakes before they occur. Scientifically, there is no established explanation for such symptoms, and more often than not, there is no earthquake following these reported sensations.
-
Ground Opening During Earthquakes:
- Shallow crevasses may form during earthquake-induced events like landslides, but faults do not open up during earthquakes. The explanation correctly involves the sliding of two blocks of the Earth's crust past each other.
-
Earthquake Weather:
- The article debunks the myth of earthquake weather, tracing it back to Aristotle's theory in the 4th Century B.C. There is no scientific basis for the belief that specific weather conditions precede earthquakes.
-
Space Weather and Earthquakes:
- Solar flares and magnetic storms, categorized as "space weather," can affect technological systems, but there is no demonstrated causal relationship between space weather and earthquakes.
-
Geomagnetic Field and Earthquakes:
- Despite electromagnetic variations observed after earthquakes, there is no convincing evidence of electromagnetic precursors to earthquakes. Geophysicists acknowledge the potential benefits of such precursors for reliable earthquake prediction but have not yet demonstrated their reality.
In conclusion, the provided information covers a range of topics related to earthquakes, dispelling myths and providing accurate scientific explanations. As someone deeply immersed in this field, I find it crucial to share reliable information to enhance public understanding of seismic activity.
