Stratigraphic contact marking uplift of Montague Island, caused by slip on the Patton Bay fault system during the 1964 M9.2 Great ALaska Earthquake.
Alaska-Aleutian Subduction Zone Studies Active
By Alaska Science Center
October 9, 2018
Our research team is exploring seismic and aseismic slip along the Alaska-Aleutian arc and studying the prehistoric record of megathrust earthquakes and tsunamis along the Alaska-Aleutian subduction zone
Seismic and Aseismic Slip: Tectonic tremor and associated slow slip events represent a newly discovered part of the earthquake cycle. This research aims to understand the process generating tectonic tremor and its relationship to slow slip and earthquakes.
Paleoseismology and Paleotsunami: Despite being one of the most seismically active plate boundaries and the source of some of the largest historical earthquakes and tsunamis in the world, the earthquake prehistory of the Alaska-Aleutian subduction zone remains largely unstudied. Our research aims to reconstruct an accurate and comprehensive record of prehistoric Aleutian arc earthquakes and tsunamis to understand the frequency and origin of great earthquakes and damaging tsunamis sourced in the Aleutians. The findings from field campaigns in the Aleutians inform earthquake and tsunami hazard assessments that underpin the National Seismic Hazard Maps.
Return to Geology >> Hazards >> Alaska Earthquake and Tsunami Hazards
Exploring Seismic and Aseismic Slip in the Alaska-Aleutian Arc
Tectonic tremor, a weak vibration of the ground detectable only through sensitive seismometers, has been identified throughout south-central Alaska. This research uses the catalog of detected tremor to provide key constraints on fault conditions, plate boundary geometry and the relationship between tremor and slow slip. We investigate the spatial and temporal characteristics of tectonic tremor and slow slip phenomena in Alaska’s diverse tectonic environments, and relate it to earthquakes and slow slip in order to elucidate factors controlling tremor and complement similar studies in the contiguous United States.
Alaska-Aleutian Paleoseismology and Paleotsunami Studies
This research quantifies the timing, location, and size of large prehistoric earthquakes on upper-plate and plate-boundary faults, and the tsunamis that may accompany them, between Prince William Sound and the western Aleutians. We assess these parameters through comprehensive paleoseismology and paleotsunami studies at sites on the south-facing coasts of the Aleutian, Kodiak and Semidi Islands and the Patton Bay fault system in Prince William Sound. Fieldwork involves USGS scientists and academic collaborators. We develop histories of past earthquakes and tsunamis through extensive stratigraphic and geomorphic field studies, paleontologic analyses, tephrachronology, and radiometric dating. The paleoseismic and paleotsunami data we gather in the field ultimately contributes to the assessment of earthquake and tsunami hazards throughout western North America, including USGS National Seismic Hazard Maps and tsunami inundation maps developed through NOAA’s National Tsunami Hazard Mitigation Program.
Below are other science projects associated with this project.
Alaska Earthquake and Tsunami Hazards
Alaska has more large earthquakes than the rest of the United States combined. More than three-quarters of the state’s population live in an area that can experience a magnitude 7 earthquake. Our research provides objective science that helps stakeholders prepare for and mitigate the effects of future earthquakes and tsunamis, which bolsters the economic health and well-being of Alaska and the...
Alaska Seismic Hazard Map
The National Seismic Hazard Maps developed by the USGS show the spatial probability of peak earthquake-driven ground motion levels. Since the last revisions to the map for Alaska in 2007, scientists have made significant advances in understanding active faulting, fault slip rates, and fault behavior.
Characterizing the Active Queen Charlotte-Fairweather Fault System
This research aims to better characterize the earthquake potential of the southern Fairweather Fault in order to provide more accurate fault source data for the USGS National Seismic Hazard Map. Our approach interrogates lidar data and satellite imagery, applies paleoseismological methods to examine earthquake history, and leverages partnerships with USGS scientists from Colorado and California...
Below are multimedia items associated with this project.
Stratigraphic contact marking 1964 uplift of Montague Island, Alaska
Stratigraphic contact marking uplift of Montague Island, caused by slip on the Patton Bay fault system during the 1964 M9.2 Great ALaska Earthquake.
Geologists' camp on Unga Island, Alaska
USGS geologists' camp overlooking Unga Village on Unga Island, Alaska.
USGS geologists' camp overlooking Unga Village on Unga Island, Alaska.
Sediment core showing tsunami deposits on Sitkalidak Island, Alaska
Sediment core showing sandy tsunami deposits over soil from an upland environment on Sitkalidak Island, Alaska.
Sediment core showing sandy tsunami deposits over soil from an upland environment on Sitkalidak Island, Alaska.
Soil pit on Sitkalidak Island, Alaska
Soil pit exposing tsunami deposits on Sitkalidak Island, Alaska.
Soil pit exposing tsunami deposits on Sitkalidak Island, Alaska.
USGS team looking at a tsunami-rafted log above Stardust Bay, Alaska
USGS Alaska Earthquake Hazards research team investigates a tsunami-rafted drift log high above sea level at Stardust Bay, Sedanka Island, Alaska.
USGS Alaska Earthquake Hazards research team investigates a tsunami-rafted drift log high above sea level at Stardust Bay, Sedanka Island, Alaska.
- Overview
Our research team is exploring seismic and aseismic slip along the Alaska-Aleutian arc and studying the prehistoric record of megathrust earthquakes and tsunamis along the Alaska-Aleutian subduction zone
Seismic and Aseismic Slip: Tectonic tremor and associated slow slip events represent a newly discovered part of the earthquake cycle. This research aims to understand the process generating tectonic tremor and its relationship to slow slip and earthquakes.
Paleoseismology and Paleotsunami: Despite being one of the most seismically active plate boundaries and the source of some of the largest historical earthquakes and tsunamis in the world, the earthquake prehistory of the Alaska-Aleutian subduction zone remains largely unstudied. Our research aims to reconstruct an accurate and comprehensive record of prehistoric Aleutian arc earthquakes and tsunamis to understand the frequency and origin of great earthquakes and damaging tsunamis sourced in the Aleutians. The findings from field campaigns in the Aleutians inform earthquake and tsunami hazard assessments that underpin the National Seismic Hazard Maps.
Return to Geology >> Hazards >> Alaska Earthquake and Tsunami Hazards
Exploring Seismic and Aseismic Slip in the Alaska-Aleutian Arc
Tectonic tremor, a weak vibration of the ground detectable only through sensitive seismometers, has been identified throughout south-central Alaska. This research uses the catalog of detected tremor to provide key constraints on fault conditions, plate boundary geometry and the relationship between tremor and slow slip. We investigate the spatial and temporal characteristics of tectonic tremor and slow slip phenomena in Alaska’s diverse tectonic environments, and relate it to earthquakes and slow slip in order to elucidate factors controlling tremor and complement similar studies in the contiguous United States.
Alaska-Aleutian Paleoseismology and Paleotsunami Studies
This research quantifies the timing, location, and size of large prehistoric earthquakes on upper-plate and plate-boundary faults, and the tsunamis that may accompany them, between Prince William Sound and the western Aleutians. We assess these parameters through comprehensive paleoseismology and paleotsunami studies at sites on the south-facing coasts of the Aleutian, Kodiak and Semidi Islands and the Patton Bay fault system in Prince William Sound. Fieldwork involves USGS scientists and academic collaborators. We develop histories of past earthquakes and tsunamis through extensive stratigraphic and geomorphic field studies, paleontologic analyses, tephrachronology, and radiometric dating. The paleoseismic and paleotsunami data we gather in the field ultimately contributes to the assessment of earthquake and tsunami hazards throughout western North America, including USGS National Seismic Hazard Maps and tsunami inundation maps developed through NOAA’s National Tsunami Hazard Mitigation Program.
- Science
Below are other science projects associated with this project.
Alaska Earthquake and Tsunami Hazards
Alaska has more large earthquakes than the rest of the United States combined. More than three-quarters of the state’s population live in an area that can experience a magnitude 7 earthquake. Our research provides objective science that helps stakeholders prepare for and mitigate the effects of future earthquakes and tsunamis, which bolsters the economic health and well-being of Alaska and the...Alaska Seismic Hazard Map
The National Seismic Hazard Maps developed by the USGS show the spatial probability of peak earthquake-driven ground motion levels. Since the last revisions to the map for Alaska in 2007, scientists have made significant advances in understanding active faulting, fault slip rates, and fault behavior.Characterizing the Active Queen Charlotte-Fairweather Fault System
This research aims to better characterize the earthquake potential of the southern Fairweather Fault in order to provide more accurate fault source data for the USGS National Seismic Hazard Map. Our approach interrogates lidar data and satellite imagery, applies paleoseismological methods to examine earthquake history, and leverages partnerships with USGS scientists from Colorado and California... - Multimedia
Below are multimedia items associated with this project.
Stratigraphic contact marking 1964 uplift of Montague Island, AlaskaStratigraphic contact marking uplift of Montague Island, caused by slip on the Patton Bay fault system during the 1964 M9.2 Great ALaska Earthquake.
Stratigraphic contact marking uplift of Montague Island, caused by slip on the Patton Bay fault system during the 1964 M9.2 Great ALaska Earthquake.
Geologists' camp on Unga Island, AlaskaUSGS geologists' camp overlooking Unga Village on Unga Island, Alaska.
USGS geologists' camp overlooking Unga Village on Unga Island, Alaska.
Sediment core showing tsunami deposits on Sitkalidak Island, AlaskaSediment core showing sandy tsunami deposits over soil from an upland environment on Sitkalidak Island, Alaska.
Sediment core showing sandy tsunami deposits over soil from an upland environment on Sitkalidak Island, Alaska.
Soil pit on Sitkalidak Island, AlaskaSoil pit exposing tsunami deposits on Sitkalidak Island, Alaska.
Soil pit exposing tsunami deposits on Sitkalidak Island, Alaska.
USGS team looking at a tsunami-rafted log above Stardust Bay, AlaskaUSGS Alaska Earthquake Hazards research team investigates a tsunami-rafted drift log high above sea level at Stardust Bay, Sedanka Island, Alaska.
USGS Alaska Earthquake Hazards research team investigates a tsunami-rafted drift log high above sea level at Stardust Bay, Sedanka Island, Alaska.
- Publications