PubTalk 1/2018 — ShakeAlert: Path to West Coast EQ Early Warning
PubTalk 1/2018 — ShakeAlert: Path to West Coast EQ Early WarningTitle: ShakeAlert: The Path to West Coast Earthquake Early Warning ... how a few seconds can save lives and property
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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) the date and time, 2) the location, and 3) the magnitude.
Yes, some people say they can predict earthquakes, but here are the reasons why their statements are false:
If an earthquake happens to occur that remotely fits their prediction, they claim success even though one or more of their predicted elements is wildly different from what actually occurred, so it is therefore a failed prediction.
Predictions (by non-scientists) usually start swirling around social media when something happens that is thought to be a precursor to an earthquake in the near future. The so-called precursor is often a swarm of small earthquakes, increasing amounts of radon in local water, unusual behavior of animals, increasing size of magnitudes in moderate size events, or a moderate-magnitude event rare enough to suggest that it might be a foreshock.
Unfortunately, most such precursors frequently occur without being followed by an earthquake, so a real prediction is not possible. Instead, if there is a scientific basis, a forecast might be made in probabilistic terms. See: What is the difference between earthquake early warning, earthquake forecasts, earthquake probabilities, and earthquake prediction?
An earthquake forecast was made in China several decades ago based on small earthquakes and unusual animal activity. Many people chose to sleep outside of their homes and thus were spared when the main earthquake indeed occurred and caused widespread destruction. However, this type of seismic activity is rarely followed by a large earthquake and, unfortunately, most earthquakes have no precursory events whatsoever. The next large earthquake in China had no precursors and thousands of people died.
The USGS focuses its efforts on the long-term mitigation of earthquake hazards and by helping to improve the safety of structures, rather than by trying to accomplish short-term predictions.
Learn more:
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...
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...
The USGS uses these four terms to refer to four different things. Early warning is a notification that is issued after an earthquake starts. Probabilities and forecasts are comparable to climate probabilities and weather forecasts, while predictions are more like statements of when, where, and how large, which is not yet possible for earthquakes. Here are more detailed descriptions of each...
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...
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.
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...
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...
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...
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...
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
Title: ShakeAlert: The Path to West Coast Earthquake Early Warning ... how a few seconds can save lives and property
Title: ShakeAlert: The Path to West Coast Earthquake Early Warning ... how a few seconds can save lives and property
Fairweather fault lidar
Fairweather fault lidar
by Morgan Page, USGS Research Geophysicist
by Morgan Page, USGS Research Geophysicist
--updating earthquake prediction--fact vs. fiction
by Susan Hough, USGS Seismologist
--updating earthquake prediction--fact vs. fiction
by Susan Hough, USGS Seismologist
The recent, devastating earthquake in China has sparked discussion about whether earthquakes can be predicted. USGS scientist Mike Blanpied sets the record straight on what science is capable of.
The recent, devastating earthquake in China has sparked discussion about whether earthquakes can be predicted. USGS scientist Mike Blanpied sets the record straight on what science is capable of.
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...
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...
The USGS uses these four terms to refer to four different things. Early warning is a notification that is issued after an earthquake starts. Probabilities and forecasts are comparable to climate probabilities and weather forecasts, while predictions are more like statements of when, where, and how large, which is not yet possible for earthquakes. Here are more detailed descriptions of each...
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...
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.
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...
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...
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...
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...
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
Title: ShakeAlert: The Path to West Coast Earthquake Early Warning ... how a few seconds can save lives and property
Title: ShakeAlert: The Path to West Coast Earthquake Early Warning ... how a few seconds can save lives and property
Fairweather fault lidar
Fairweather fault lidar
by Morgan Page, USGS Research Geophysicist
by Morgan Page, USGS Research Geophysicist
--updating earthquake prediction--fact vs. fiction
by Susan Hough, USGS Seismologist
--updating earthquake prediction--fact vs. fiction
by Susan Hough, USGS Seismologist
The recent, devastating earthquake in China has sparked discussion about whether earthquakes can be predicted. USGS scientist Mike Blanpied sets the record straight on what science is capable of.
The recent, devastating earthquake in China has sparked discussion about whether earthquakes can be predicted. USGS scientist Mike Blanpied sets the record straight on what science is capable of.