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.
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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.
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.
Earthquakes on the island of Hawaii
Figure 2.
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.
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.
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
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.
The map is based on the USGS models for the conterminous U.S. (2018), Hawaii (1998), and Alaska (2007).
link2018 Long-term National Seismic Hazard Map. Earthquake hazard map showing peak ground accelerations having a 2 percent probability of being exceeded in 50 years, for a firm rock site. The map is based on the most recent USGS models for the conterminous U.S.
The map is based on the USGS models for the conterminous U.S. (2018), Hawaii (1998), and Alaska (2007).
link2018 Long-term National Seismic Hazard Map. Earthquake hazard map showing peak ground accelerations having a 2 percent probability of being exceeded in 50 years, for a firm rock site. The map is based on the most recent USGS models for the conterminous U.S.
ANSS US Stations
Map of free-field seismic stations across the United States (circa 2020) that are operated by national and regional seismic networks of the ANSS. The background shading indicates seismic hazard as defined in the USGS National Seismic Hazard Model. Regions with lighter highlighting have comparatively higher seismic hazard.
Map of free-field seismic stations across the United States (circa 2020) that are operated by national and regional seismic networks of the ANSS. The background shading indicates seismic hazard as defined in the USGS National Seismic Hazard Model. Regions with lighter highlighting have comparatively higher seismic hazard.
Death Valley Fault DEM Collection
Nadine Reitman walks with a camera on a 20-foot pole to generate high resolution DEM’s of the Death Valley fault, May, 2021.
Nadine Reitman walks with a camera on a 20-foot pole to generate high resolution DEM’s of the Death Valley fault, May, 2021.
Stanley Lake Cracks from Stanley, Idaho Earthquake Liquefaction
Liquefaction-related features and cracks along the sandy shore next to Stanley Lake.
Liquefaction-related features and cracks along the sandy shore next to Stanley Lake.
2020 Southwest Puerto Rico Earthquake Sequence (Jan 29, 2020)
The U.S. Geological Survey has released a report on the potential duration of aftershocks of the 2020 Southwest Puerto Rico earthquake sequence (series) to guide public policy decisions, other actions, and help people stay safe and care for themselves and each other.
The U.S. Geological Survey has released a report on the potential duration of aftershocks of the 2020 Southwest Puerto Rico earthquake sequence (series) to guide public policy decisions, other actions, and help people stay safe and care for themselves and each other.
Secuencia del Terremoto del 2020 en el Suroeste de Puerto Rico
El Servicio Geológico de los EE. UU. ha publicado un informe sobre la duración potencial de las réplicas de la secuencia (serie) del terremoto del Suroeste de Puerto Rico en el 2020 que puede ser usado como guía en las decisiones de política pública, otras acciones y ayudar a las personas a mantenerse seguras y cuidarse a sí mismas y a los demás.
El Servicio Geológico de los EE. UU. ha publicado un informe sobre la duración potencial de las réplicas de la secuencia (serie) del terremoto del Suroeste de Puerto Rico en el 2020 que puede ser usado como guía en las decisiones de política pública, otras acciones y ayudar a las personas a mantenerse seguras y cuidarse a sí mismas y a los demás.
2020 Puerto Rico Earthquake Sequence (as of Jan. 16, 2020)
Earthquakes detected between December 28, 2019 as of January 16, 2020. Subject to updates.
>300 M3+earthquakes recorded*
since Dec. 28, 2019 (within 40km) strong enough to be felt
10 M5+ earthquakes recorded*
since Dec. 28, 2019 (including M6.4) large enough to do damage
Earthquakes detected between December 28, 2019 as of January 16, 2020. Subject to updates.
>300 M3+earthquakes recorded*
since Dec. 28, 2019 (within 40km) strong enough to be felt
10 M5+ earthquakes recorded*
since Dec. 28, 2019 (including M6.4) large enough to do damage
Secuencia del Terremoto en Puerto Rico, 2020 (hasta enero 16, 2020)
Terremotos detectados entre diciembre 28, 2019 hasta enero 16, 2020. Sujeto a actualizaciones.
>300 M3+ terremotos* registrados
desde dic 28, 2019 (dentro de 40km) suficientemente fuerte como para ser sentido
10 M5+ terremotos* registrados
Terremotos detectados entre diciembre 28, 2019 hasta enero 16, 2020. Sujeto a actualizaciones.
>300 M3+ terremotos* registrados
desde dic 28, 2019 (dentro de 40km) suficientemente fuerte como para ser sentido
10 M5+ terremotos* registrados
USGS and NBRO Scientists in Sri Lanka
USGS scientists collaborate with Sri Lankan scientists from the National Building Research Organization (NBRO) on the installation of rainfall and soil moisture instrumentation on an active landslide in southwest Sri Lanka. The station provides real-time data including rainfall and soil moisture content of an active landslide.
USGS scientists collaborate with Sri Lankan scientists from the National Building Research Organization (NBRO) on the installation of rainfall and soil moisture instrumentation on an active landslide in southwest Sri Lanka. The station provides real-time data including rainfall and soil moisture content of an active landslide.
BMKG 2019 Staff Photo
Thirty Bureau of Meteorology, Climatology and Geophysics (BMKG) senior staff members received USGS/IRIS training in Advanced Seismology and Tsunami Warnings (Oct. 14-18, 2019). Most of the staff members are in this photo.
Thirty Bureau of Meteorology, Climatology and Geophysics (BMKG) senior staff members received USGS/IRIS training in Advanced Seismology and Tsunami Warnings (Oct. 14-18, 2019). Most of the staff members are in this photo.
Photo of Participants During BMKG Training
Photo of students in October 2019 during lectures at Bureau of Meteorology, Climatology and Geophysics (BMKG) College (STMKG).
Photo of students in October 2019 during lectures at Bureau of Meteorology, Climatology and Geophysics (BMKG) College (STMKG).
M7.1 Ridgecrest, California Earthquake Rupture Moletrack
Belle Philibosian field mapping the M7.1 Ridgecrest, California Earthquake Rupture, July 9, 2019.
Belle Philibosian field mapping the M7.1 Ridgecrest, California Earthquake Rupture, July 9, 2019.
San Andreas Fault Near Bitterwater, California
Looking south along the creeping section of the San Andreas Fault near Bitterwater, California, September 23, 2019.
Looking south along the creeping section of the San Andreas Fault near Bitterwater, California, September 23, 2019.
Jim Smith Inside Lucchetti Dam in Puerto Rico
Jim Smith working on cabling inside of Lucchetti dam in Puerto Rico, assisting the Puerto Rico Strong Motion Program with Hurricane Maria recovery efforts.
Jim Smith working on cabling inside of Lucchetti dam in Puerto Rico, assisting the Puerto Rico Strong Motion Program with Hurricane Maria recovery efforts.