Skip to main content
U.S. flag

An official website of the United States government

Images

Images intro.
Filter Total Items: 523
Globe with blue ocean and green continents.  A red triangle is labelled "Seismograph Station" with a yellow star labelled "Local Earthquake" a bit south, both in California.  There is another yellow star in the middle of the Atlantic Ocean labelled "Teleseismic Earthquake".
Teleseismic
Teleseismic
Teleseismic

Teleseismic is pertaining to earthquakes at distances greater than 1,000 km from the measurement site.

Teleseismic is pertaining to earthquakes at distances greater than 1,000 km from the measurement site.

Graph with "Time (sec)" on the x-axis and "Component" on the y-axis.  The components as listed on the y-axis are Z, N, E, Z, N, E.  The top three are blue and the bottom three are green.  The plots present in squiggly waves
Time History
Time History
Time History

The time history is the sequence of values of any time-varying quantity (such as a ground motion measurement) measured at a set of fixed times. Also termed time series.

The time history is the sequence of values of any time-varying quantity (such as a ground motion measurement) measured at a set of fixed times. Also termed time series.

Map of the west coast of the United States showing the tectonic setting
Transform Fault
Transform Fault
Transform Fault

A transform fault is a special variety of strike-slip fault that accommodates relative horizontal slip between other tectonic elements, such as oceanic crustal plates. Often extend from oceanic ridges.

A transform fault is a special variety of strike-slip fault that accommodates relative horizontal slip between other tectonic elements, such as oceanic crustal plates. Often extend from oceanic ridges.

Map of coast with dark gray as the land and dark blue as the ocean with different colored lines for slip rate values across the land
Slip Rate Map
Slip Rate Map
Slip Rate Map

The slip rate is how fast the two sides of a fault are slipping relative to one another, as determined from geodetic measurements, from offset man-made structures, or from offset geologic features whose age can be estimated. It is measured parallel to the predominant slip direction or estimated from the vertical or horizontal offset of geologic markers.

The slip rate is how fast the two sides of a fault are slipping relative to one another, as determined from geodetic measurements, from offset man-made structures, or from offset geologic features whose age can be estimated. It is measured parallel to the predominant slip direction or estimated from the vertical or horizontal offset of geologic markers.

Soil profile with grass and dark brown soil at the top, followed by a light tan soil, then a thinner reddish soil band, and another tan layer of soil at the bottom.
Soil Profile in Hills of Manisa Province, Turkey
Soil Profile in Hills of Manisa Province, Turkey
Soil Profile in Hills of Manisa Province, Turkey

Soil profile in hills of Manisa Province, Turkey, showing a distinct horizon of accumulated red-purple metallic (manganese and/or iron?) oxides.

Soil profile in hills of Manisa Province, Turkey, showing a distinct horizon of accumulated red-purple metallic (manganese and/or iron?) oxides.

Block diagram with a labelled earthquake source shown as a circle on the fault plane and directly underneath the center of the produced circular, seismic waves
Earthquake Source Diagram
Earthquake Source Diagram
Earthquake Source Diagram

The source is the term for the released forces that generate acoustic or seismic waves, also called the earthquake source.

The source is the term for the released forces that generate acoustic or seismic waves, also called the earthquake source.

Diagram showing P waves (small jolt or light shaking or not felt), S waves (larger jolt or strong shaking), and surface waves (rolling motion))
P Waves
P Waves
P Waves

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.

Person in yellow hat sitting on the ground and looking into a green valley with clouds surrounding snow-topped mountains
Person Looking at Valley
Person Looking at Valley
Person Looking at Valley

Person sitting and overlooking valley of snow-topped mountains with clouds in between mountains 

Person sitting and overlooking valley of snow-topped mountains with clouds in between mountains 

Black background with a green wave and a white arrow pointing across one concave and one convex hump to indicate a period
Period
Period
Period

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.

World map with different colored outlines to show tectonic plates
Plate Tectonics Map
Plate Tectonics Map
Plate Tectonics Map

Plate Tectonics is the theory supported by a wide range of evidence that considers the earth's crust and upper mantle to be composed of several large, thin, relatively rigid plates that move relative to one another. Slip on faults that define the plate boundaries commonly results in earthquakes.

Plate Tectonics is the theory supported by a wide range of evidence that considers the earth's crust and upper mantle to be composed of several large, thin, relatively rigid plates that move relative to one another. Slip on faults that define the plate boundaries commonly results in earthquakes.

Photo of ripples in a pond with the reflection of a cloudy sky
Pond Ripples (Attenuation)
Pond Ripples (Attenuation)
Pond Ripples (Attenuation)

Ripples on a pond are attenuated as they move away from the source. Q is the inverse of attenuation. A high Q means a low attenuation.

Ripples on a pond are attenuated as they move away from the source. Q is the inverse of attenuation. A high Q means a low attenuation.

Geologic time scale showing eras, periods, and notable events in terms of millions of years ago
Geologic Time Scale 3
Geologic Time Scale 3
Geologic Time Scale 3

Geologic time scale showing eras, periods, and notable events in terms of millions of years ago.

Geologic time scale showing eras, periods, and notable events in terms of millions of years ago.

A stress vs time graph showing fault strength and an offset across fault vs time graph
Recurrence Interval
Recurrence Interval
Recurrence Interval

A stress vs time graph showing fault strength and an offset across fault vs time graph 

A stress vs time graph showing fault strength and an offset across fault vs time graph 

Illustration showing a wave reflecting off of the boundary between Rock Type 1 and Rock Type 2
Reflected Wave
Reflected Wave
Reflected Wave

The reflection is the energy or wave from an earthquake that has been returned (reflected) from an boundary between two different materials within the earth, just as a mirror reflects light.

The reflection is the energy or wave from an earthquake that has been returned (reflected) from an boundary between two different materials within the earth, just as a mirror reflects light.

Illustration showing an angled downward vector in two scenarios: The first shows a vector going through Rock Type 1 and then getting a less steep slope in Rock Type 2, meaning the velocity in rock type 2 is greater than velocity in rock type 1; and the second shows a vector going through Rock Type 1 and then getting a more steep slope in Rock Type 2, meaning the velocity in rock type 2 is less than velocity in rock type 1
Refraction
Refraction
Refraction

Refraction is (1) the deflection, or bending, of the ray path of a seismic wave caused by its passage from one material to another having different elastic properties. (2) bending of a tsunami wave front owing to variations in the water depth along a coastline.

Refraction is (1) the deflection, or bending, of the ray path of a seismic wave caused by its passage from one material to another having different elastic properties. (2) bending of a tsunami wave front owing to variations in the water depth along a coastline.

Chance of earthquakes in Hawaii
Chance of earthquakes in Hawaii
Chance of earthquakes in Hawaii
Chance of earthquakes in Hawaii

Figure 1. Chance of minor or greater damaging earthquake shaking in the next 100 years. Population exposure estimates are rounded to the nearest 1000. 

Figure 1. Chance of minor or greater damaging earthquake shaking in the next 100 years. Population exposure estimates are rounded to the nearest 1000. 

Seismicity of Hawaii from 2021 Hawaii National Seismic Hazard Map
Figure 3. Seismicity of Hawaii from 2021 Hawaii National Seismic Hazard Map
Figure 3. Seismicity of Hawaii from 2021 Hawaii National Seismic Hazard Map
Figure 3. Seismicity of Hawaii from 2021 Hawaii National Seismic Hazard Map

Seismicity of Hawaii: earthquakes M>5 from the 1840-1899, 1900-1959, 1960-2019 catalogs shown separately. While earthquake activity remains high today, it seems to have decreased over the past 60 years, which could be related to less volcanic activity at Mauna Loa. 

Seismicity of Hawaii: earthquakes M>5 from the 1840-1899, 1900-1959, 1960-2019 catalogs shown separately. While earthquake activity remains high today, it seems to have decreased over the past 60 years, which could be related to less volcanic activity at Mauna Loa. 

digging machine on grassy meadow with large white windmills in background
Sediment Investigations in the San Joaquin – Sacramento Delta
Sediment Investigations in the San Joaquin – Sacramento Delta
Sediment Investigations in the San Joaquin – Sacramento Delta

USGS Geologists R. Sickler, J. Willard, and B. Philibosian observe as an excavator digs a pit used to investigate sediments uplifted by active tectonic activity in the San Joaquin – Sacramento Delta, California, November 29, 2021.

USGS Geologists R. Sickler, J. Willard, and B. Philibosian observe as an excavator digs a pit used to investigate sediments uplifted by active tectonic activity in the San Joaquin – Sacramento Delta, California, November 29, 2021.

Infographic on the 2011 Virginia Earthquake and East Coast Earthquake Hazards
2011 Virginia Earthquake - Infographic
2011 Virginia Earthquake - Infographic
2011 Virginia Earthquake - Infographic

USGS infographic on the magnitude 5.8 earthquake that struck central Virginia August 23, 2011, east coast earthquake hazards and how the USGS is helping inform critical decisions to protect lives and property. 

Full Text Description:

10-YEAR ANNIVERSARY OF THE M5.8 EARTHQUAKE IN VIRGINIA
America’s Most Widely Felt Earthquake

USGS infographic on the magnitude 5.8 earthquake that struck central Virginia August 23, 2011, east coast earthquake hazards and how the USGS is helping inform critical decisions to protect lives and property. 

Full Text Description:

10-YEAR ANNIVERSARY OF THE M5.8 EARTHQUAKE IN VIRGINIA
America’s Most Widely Felt Earthquake

USGS scientist with yellow visibility safety vest on talking to the camera with people working in the background.
Joanne Chan - Seismic Survey
Joanne Chan - Seismic Survey
Joanne Chan - Seismic Survey

Joanne Chan conducting a seismic survey in San Carlos, California, looking for traces of the Serra Fault. 

Joanne Chan conducting a seismic survey in San Carlos, California, looking for traces of the Serra Fault. 

Was this page helpful?