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Earthquake Hazards Program images.
Photo of participants working on training material on laptops.
The USGS training at the Bureau of Meteorology, Climatology and Geophysics (BMKG) includes hands-on activities. The BMKG staff are highly capable and have received an excellent educational background at the BMKG College or National University.
Photo of participants working on training material on laptops.
The USGS training at the Bureau of Meteorology, Climatology and Geophysics (BMKG) includes hands-on activities. The BMKG staff are highly capable and have received an excellent educational background at the BMKG College or National University.
Dr, Walter Mooney with three Bureau of Meteorology, Climatology and Geophysics (BMKG) training participants in Palu, Sulawesi.
Dr, Walter Mooney with three Bureau of Meteorology, Climatology and Geophysics (BMKG) training participants in Palu, Sulawesi.
Photo of a Kinemetrics FBA-23 accelerograph. The device is black and square with rounded edges on a green background.
Photo of a Kinemetrics FBA-23 accelerograph. The device is black and square with rounded edges on a green background.
Cross-section of the Benioff zone resulting from a by the interaction of a downgoing oceanic crustal plate with a continental plate.
Cross-section of the Benioff zone resulting from a by the interaction of a downgoing oceanic crustal plate with a continental plate.
When seismologists think of an earthquake, this image of a seismogram is what comes to their minds.
When seismologists think of an earthquake, this image of a seismogram is what comes to their minds.
Diagram of dipping slab with different focal depth events. The focal depth refers to the depth of an earthquake hypocenter.
Diagram of dipping slab with different focal depth events. The focal depth refers to the depth of an earthquake hypocenter.
The geologic time scale showing each eon, era, period, epoch, and their associated ages.
The geologic time scale showing each eon, era, period, epoch, and their associated ages.
Photo of bridge. Geotechnical means referring to the use of scientific methods and engineering principles to acquire, interpret, and apply knowledge of earth materials for solving engineering problems.
Photo of bridge. Geotechnical means referring to the use of scientific methods and engineering principles to acquire, interpret, and apply knowledge of earth materials for solving engineering problems.
Horst and graben diagram. A graben is a down-dropped block of the earth's crust resulting from extension, or pulling, of the crust.
Horst and graben diagram. A graben is a down-dropped block of the earth's crust resulting from extension, or pulling, of the crust.
Iceland and plate motions. Kinematic refers to the general movement patterns and directions of the earth's rocks that produce rock deformation.
Iceland and plate motions. Kinematic refers to the general movement patterns and directions of the earth's rocks that produce rock deformation.
Plot showing least squares fit. When plotting data points on a graph, the least-squares-fit is the line or curve that comes closest to going through all the points.
Plot showing least squares fit. When plotting data points on a graph, the least-squares-fit is the line or curve that comes closest to going through all the points.
The Landers fault (red lines at left) and the Hector Mine fault and its aftershocks (red lines and circles at right). The Hector Mine earthquake was a magnitude 7.1, and it produced thousands of aftershocks.
The Landers fault (red lines at left) and the Hector Mine fault and its aftershocks (red lines and circles at right). The Hector Mine earthquake was a magnitude 7.1, and it produced thousands of aftershocks.
The natural frequency is the frequency at which a particular object or system vibrates when pushed by a single force or impulse, and not influenced by other external forces or by damping. If you hold a slinky by one end and let it hang down and then give it one push up from the bottom, the rate of up-and-down motion is its natural frequency.
The natural frequency is the frequency at which a particular object or system vibrates when pushed by a single force or impulse, and not influenced by other external forces or by damping. If you hold a slinky by one end and let it hang down and then give it one push up from the bottom, the rate of up-and-down motion is its natural frequency.
This turn-of-the-century wooden residence in Los Gatos sustained major damage when it moved off its foundation during the October 17, 1989, M7.1 Loma Prieta, California earthquake.
This turn-of-the-century wooden residence in Los Gatos sustained major damage when it moved off its foundation during the October 17, 1989, M7.1 Loma Prieta, California earthquake.
A surface wave is a seismic seismic wave that is trapped near the surface of the earth.
A surface wave is a seismic seismic wave that is trapped near the surface of the earth.
A tsunami is a sea wave of local or distant origin that results from large-scale seafloor displacements associated with large earthquakes, major submarine slides, or exploding volcanic islands.
A tsunami is a sea wave of local or distant origin that results from large-scale seafloor displacements associated with large earthquakes, major submarine slides, or exploding volcanic islands.
A P wave, or compressional wave, is a seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.
A P wave, or compressional wave, is a seismic body wave that shakes the ground back and forth in the same direction and the opposite direction as the direction the wave is moving.
Diagram of period. The period is the time interval required for one full cycle of a wave.
Diagram of period. The period is the time interval required for one full cycle of a wave.
A seismogram is a record written by a seismograph in response to ground motions produced by an earthquake, explosion, or other ground-motion sources.
A seismogram is a record written by a seismograph in response to ground motions produced by an earthquake, explosion, or other ground-motion sources.
A slab is the oceanic crustal plate that underthrusts the continental plate in a subduction zone and is consumed by the earth's mantle.
A slab is the oceanic crustal plate that underthrusts the continental plate in a subduction zone and is consumed by the earth's mantle.
Moment = ? A D
? = shear modulus = 32 GPa in crust, 75 GPa in mantle
A = LW = area
D = average displacement during rupture
Moment = ? A D
? = shear modulus = 32 GPa in crust, 75 GPa in mantle
A = LW = area
D = average displacement during rupture