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Browse images and videos related to earthquakes and earthquake hazards.
Aftershock Forecast Sequence-Specific Model Parameters equation
The probability distribution for the number of aftershocks, P(N), and the forecast can then be computed using the same procedures as for the generic model, using Pseq-spec(a) instead of Pgeneric(a).
Aftershock Forecast Sequence-Specific Model Parameters equation
The probability distribution for the number of aftershocks, P(N), and the forecast can then be computed using the same procedures as for the generic model, using Pseq-spec(a) instead of Pgeneric(a).
An example of Bayesian updating of productivity parameter (a-value) for the 2010 Mw 8.8 Maule, Chile, earthquake. Immediately following the earthquake, the SZ-GENERIC region-specific a-value distribution can be used.
An example of Bayesian updating of productivity parameter (a-value) for the 2010 Mw 8.8 Maule, Chile, earthquake. Immediately following the earthquake, the SZ-GENERIC region-specific a-value distribution can be used.
Screenshot of the Aftershock Forecast for an earthquake in California, showing the information box at the top of the forecast and the four tabs of forecast information.
Screenshot of the Aftershock Forecast for an earthquake in California, showing the information box at the top of the forecast and the four tabs of forecast information.
Equation 2 for the Aftershock Forecast probability distribution to compute the forecast
Equation 2 for the Aftershock Forecast probability distribution to compute the forecast
Icon used to refer to ShakeMap on Product landing pages. For example use, see https://staging-earthquake.usgs.gov/data/pager/background.php.
Icon used to refer to ShakeMap on Product landing pages. For example use, see https://staging-earthquake.usgs.gov/data/pager/background.php.
Two example aftershock sequences, from southern California, that illustrate the three general rules of aftershocks. A circle shows each aftershock's time of occurrence (horizontal axis) and magnitude (vertical axis). The larger-magnitude M6.7 Northridge earthquake is followed by many more aftershocks than the smaller M5.1 La Habra earthquake.
Two example aftershock sequences, from southern California, that illustrate the three general rules of aftershocks. A circle shows each aftershock's time of occurrence (horizontal axis) and magnitude (vertical axis). The larger-magnitude M6.7 Northridge earthquake is followed by many more aftershocks than the smaller M5.1 La Habra earthquake.
Ammonia or ammonium? What’s the difference? In water, ammonia (NH3) and ammonium (NH4+) exist together in an equilibrium that depends on pH and temperature. As the temperature or pH rise, ammonia (NH3) becomes more abundant. This is important because ammonia is more toxic than ammonium.
Ammonia or ammonium? What’s the difference? In water, ammonia (NH3) and ammonium (NH4+) exist together in an equilibrium that depends on pH and temperature. As the temperature or pH rise, ammonia (NH3) becomes more abundant. This is important because ammonia is more toxic than ammonium.
USGS Scientist, Bob deGroot, briefly explains what happened during the magnitude 7.0 earthquake that occurred offshore of Mendocino, CA, on December 5, 2024.
The event occurred in an area called the Triple Junction, where the Pacific, Juan de Fruca, and North American tectonic plates meet.
USGS Scientist, Bob deGroot, briefly explains what happened during the magnitude 7.0 earthquake that occurred offshore of Mendocino, CA, on December 5, 2024.
The event occurred in an area called the Triple Junction, where the Pacific, Juan de Fruca, and North American tectonic plates meet.
USGS Scientist, Bob deGroot, briefly explains what happened during the magnitude 7.0 earthquake that occurred offshore of Mendocino, CA, on December 5, 2024.
The event occurred in an area called the Triple Junction, where the Pacific, Juan de Fruca, and North American tectonic plates meet.
USGS Scientist, Bob deGroot, briefly explains what happened during the magnitude 7.0 earthquake that occurred offshore of Mendocino, CA, on December 5, 2024.
The event occurred in an area called the Triple Junction, where the Pacific, Juan de Fruca, and North American tectonic plates meet.
The 1989 Loma Prieta earthquake, measuring magnitude 6.9, was the strongest to hit the San Francisco Bay Area since the Great San Francisco earthquake of 1906. Although it provided extensive data on ground shaking, the available observations don’t fully capture all the quake's important features.
The 1989 Loma Prieta earthquake, measuring magnitude 6.9, was the strongest to hit the San Francisco Bay Area since the Great San Francisco earthquake of 1906. Although it provided extensive data on ground shaking, the available observations don’t fully capture all the quake's important features.
At the USGS National Earthquake Information Center (NEIC), our team locates and researches earthquakes to provide information on how to reduce risk from earthquakes.
At the USGS National Earthquake Information Center (NEIC), our team locates and researches earthquakes to provide information on how to reduce risk from earthquakes.
At the USGS National Earthquake Information Center (NEIC), our team locates and researches earthquakes to provide information on how to reduce risk from earthquakes.
At the USGS National Earthquake Information Center (NEIC), our team locates and researches earthquakes to provide information on how to reduce risk from earthquakes.
USGS scientists remember where they were during the 1992 Landers earthquake in Southern California
USGS scientists remember where they were during the 1992 Landers earthquake in Southern California
USGS seismologist Susan Hough recalls what the 1992 Landers earthquake felt like from Pasadena, CA.
USGS seismologist Susan Hough recalls what the 1992 Landers earthquake felt like from Pasadena, CA.
USGS geologist Jonathan Matti recalls fieldwork in the Mojave Desert soon after the 1992 Landers earthquake.
USGS geologist Jonathan Matti recalls fieldwork in the Mojave Desert soon after the 1992 Landers earthquake.
USGS seismologist Andrew Michael talks about the remote location of the 1992 Landers earthquake and how researchers were able to use satellite data to better see the quake’s impacts.
USGS seismologist Andrew Michael talks about the remote location of the 1992 Landers earthquake and how researchers were able to use satellite data to better see the quake’s impacts.
USGS seismologist Susan Hough talks about her role following the 1992 Landers earthquake and seismic monitoring stations in Southern California.
USGS seismologist Susan Hough talks about her role following the 1992 Landers earthquake and seismic monitoring stations in Southern California.
USGS field technician Scott Lydeen recalls what the aftermath of the 1992 Landers earthquake looked like.
USGS field technician Scott Lydeen recalls what the aftermath of the 1992 Landers earthquake looked like.
