Stephen J. Angster, Ph.D.
(He/Him)I am a field-based and analytical research geologist with the Earthquake Science Center who specializes in earthquake geology. My research aims to understand spatial and temporal distribution of earthquakes and active fault systems. My work is primary focused in the Pacific Northwest and informs seismic hazard models and future risk.
I have conducted geologic and geophysical based studies of complex fault systems in various tectonic settings throughout the U.S and internationally. I currently lead the Pacific Northwest paleoseismic studies task group for the Earthquake Science Center of the U.S. Geological Survey. My group focuses on assessing and characterizing Quaternary active faults within the upper continental plate of the Cascadia Subduction Zone.
Professional Experience
Research Geologist, USGS ESC, 2018 - Present
Geologist, USGS GHSC, 2010 - 2013
Intern Geologist, USGS GHSC, 2008 - 2010
Education and Certifications
PhD: University of Nevada, Reno, 2018
MS: Colorado School of Mines, 2013
BS: Western Illinois University, 2006
Science and Products
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western U.S.) (ver. 3.0, December 2023)
This Data Release contains version 3.0 of two related earthquake geology databases for use in the 2023 U.S. National Seismic Hazard Model. The databases are: 1) A fault sections database (“NSHM23_FSD_v3”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) an earthquake geology site information database (“NSHM23_EQGeoDB_v3”), which contains fault slip rate cons
Data Release for Luminescence: Paleoseismic liquefaction associated with Holocene earthquakes on the Wallula Fault zone, Southeast Washington, USA
Observations of widespread liquefaction and stratigraphic and structural relationships in a trench across an ambiguous scarp are used to constrain the timing of Holocene earthquakes on the northwest-striking Wallula fault zone in southeast Washington and Oregon. Additional observations and age constraints from OSL analysis of samples collected from large-scale liquefaction features that crosscut t
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western US) (ver. 2.0, February 2022)
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ('NSHM23_FSD_v2'), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ('NSHM23_EQGeoDB_v2'), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of updates to the N
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023, version 1.0
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ("NSHM2023_FaultSections_v1"), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ("NSHM2023_EQGeoDB_v1"), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of up
2020 Update to the Quaternary Fault and Fold Database for Washington State
This release is an update to the online "Quaternary fault and fold database" for Washington State. The online database was last updated for Washington in 2014 – this 2020 update includes newly identified and modified traces and geometries for on-shore faults gleaned from new peer-reviewed studies and mapping of active faults within the state of Washington. These data contain lines representing the
Field observations and logs from the Rose Hip trench exposure across a north-facing scarp within the Seattle Fault Zone, southern Bainbridge Island, Washington
The Seattle Fault Zone is an approximately 70-km-long, east-west-trending zone of south-dipping blind reverse faults within the Puget lowland region in Washington. Because of the proximity, the Seattle Fault Zone poses a significant earthquake hazard to the Puget sound and Seattle metropolitan regions. We present preliminary mapping and trench-site information from a paleoseismic investigation acr
Logs and data from the Starthistle trench across a scarp within the Wallula Fault Zone, southeastern Washington
IntroductionThe Wallula Fault Zone is composed of a series of northwest-trending faults and folds that coincide with a prominent magnetic anomaly that extends uninterrupted for approximately 120 kilometers within the Cascadia back arc of southeastern Washington and northeastern Oregon. It is part of the geologic structures associated with the topographic lineament known as the Olympic-Wallowa line
Debris avalanches in the northern California Coast Range triggered by plate boundary earthquakes
Determining the timing and cause for ancient hillslope failures proves difficult in the western United States, yet critical as it ties directly into groundmotion estimates for hazardous events. This knowledge gap is important to confront as hillslope failures are candidates to be triggered by earthquakes along active plate boundaries. We identify two prehistoric, i.e., preinstrumental history, deb
Authors
Jessie K. Pearl, Harvey Kelsey, Stephen J. Angster, Dylan Caldwell, Ian Pryor, Brian Sherrod
Simplifying complex fault data for systems-level analysis: Earthquake geology inputs for U.S. NSHM 2023
As part of the U.S. National Seismic Hazard Model (NSHM) update planned for 2023, two databases were prepared to more completely represent Quaternary-active faulting across the western United States: the NSHM23 fault sections database (FSD) and earthquake geology database (EQGeoDB). In prior iterations of NSHM, fault sections were included only if a field-measurement-derived slip rate was estimate
Authors
Alexandra Elise Hatem, Camille Marie Collett, Richard W. Briggs, Ryan D. Gold, Stephen J. Angster, Ned Field, Peter M. Powers
Characterizing strain between rigid crustal blocks in the southern Cascadia forearc: Quaternary faults and folds of the northern Sacramento Valley, California
Topographic profiles across late Quaternary surfaces in the northern Sacramento Valley (California, USA) show offset and progressive folding on series of active east- and northeast—trending faults and folds. Optically stimulated luminescence ages on deposits draping a warped late Pleistocene river terrace yielded differential incision rates along the Sacramento River and indicate tectonic uplift e
Authors
Stephen J. Angster, Steven G. Wesnousky, Paula Figueiredo, Lewis A. Owen, Thomas Sawyer
Post-glacial Mw 7.0-7.5 earthquakes on the North Olympic fault zone, Washington
Holocene crustal faulting in the northern Olympic Peninsula of Washington State manifests in a zone of west‐northwest‐striking crustal faults herein named the North Olympic fault zone, which extends for ∼80 km∼80 km along strike and includes the Lake Creek–Boundary Creek fault to the east and the Sadie Creek fault and newly discovered scarps to the west. This study focuses on the Sadie Creek fau
Authors
Elizabeth R. Schermer, Colin B. Amos, W. Cody Duckworth, Alan Nelson, Stephen J. Angster, Jaime Delano, Brian Sherrod
Documentation of Surface Fault Rupture and Ground‐Deformation Features Produced by the 4 and 5 July 2019 Mw 6.4 and Mw 7.1 Ridgecrest Earthquake Sequence
The MwMw 6.4 and MwMw 7.1 Ridgecrest earthquake sequence occurred on 4 and 5 July 2019 within the eastern California shear zone of southern California. Both events produced extensive surface faulting and ground deformation within Indian Wells Valley and Searles Valley. In the weeks following the earthquakes, more than six dozen scientists from government, academia, and the private sector carefully
Authors
Daniel J. Ponti, James Luke Blair, Rosa Carla M, Kate Thomas, Alexandra Pickering, Sinan Akciz, Stephen J. Angster, Jean-Philipe Avouac, Jeffrey Bachhuber, Steven Bacon, Nicolas C. Barth, S. Bennett, Kelly Blake, Stephan Bork, Benjamin A. Brooks, Thomas Bullard, Paul A. Burgess, Colin Chupik, Timothy E. Dawson, Michael DeFrisco, Jaime E. Delano, Stephen B. DeLong, James D. Dolan, Andrea Donnellan, Christopher DuRoss, Todd Ericksen, Erik Frost, Gareth J. Funning, Ryan D. Gold, Nicholas A Graehl, Carlos Gutierrez, Elizabeth Haddon, Alexandra Elise Hatem, John Helms, Janis Hernandez, Christopher S. Hitchcock, Peter Holland, Kenneth W. Hudnut, Katherine J. Kendrick, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Robert Leeper, Christopher Madugo, Maxime Mareschal, James McDonald, Devin McPhillips, Christopher Milliner, Daniel Mongovin, Alexander Morelan, Stephanie Nale, Johanna Nevitt, Matt O'Neal, Brian J. Olsen, Michael Oskin, Salena Padilla, Jason Patton, Belle E. Philibosian, Ian Pierce, Cynthia Pridmore, Nathaniel Roth, David Sandwell, Katherine M. Scharer, Gordon G. Seitz, Drake Singleton, Bridget Smith-Konter, Eleanor Spangler, Brian J. Swanson, Jessica Thompson Jobe, Jerome Treiman, Francesca Valencia, Joshua Vanderwal, Alana Williams, Xiaohua Xu, Judith Zachariasen, Jade Zimmerman, Robert Zinke
Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures
Surface rupture in the 2019 Ridgecrest, California, earthquake sequence occurred along two orthogonal cross faults and includes dominantly left‐lateral and northeast‐striking rupture in the Mw 6.4 foreshock and dominantly right‐lateral and northwest‐striking rupture in the Mw 7.1 mainshock. We present >650 field‐based, surface‐displacement observations for these ruptures and synthesize our results
Authors
Christopher DuRoss, Ryan D. Gold, Timothy E. Dawson, Katherine M. Scharer, Katherine J. Kendrick, Sinan Akciz, Stephen J. Angster, Jeffery Bachhuber, Steven Bacon, Scott E.K. Bennett, Luke Blair, Benjamin A. Brooks, Thomas Bullard, W. Paul Burgess, Colin Chupik, Michael DeFrisco, Jaime Delano, James D. Dolan, Erik Frost, Nick Graehl, Elizabeth Haddon, Alexandra Elise Hatem, Janis Hernandez, Christopher S. Hitchcock, Kennth Hudnut, Jessica Thompson Jobe, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Christopher Madugo, Devin McPhillips, Christopher Milliner, Alexander Morelan, Brian Olson, Jason Patton, Belle E. Philibosian, Alexandra J. Pickering, Ian Pierce, Daniel J. Ponti, Gordon G. Seitz, Eleanor Spangler, Brian J. Swanson, Kate Thomas, Jerome Treiman, Francesca Valencia, Alana Williams, Robert Zinke
P- and S-wave velocity models incorporating the Cascadia subduction zone for 3D earthquake ground motion simulations, Version 1.6—Update for Open-File Report 2007–1348
In support of earthquake hazard studies and ground motion simulations in the Pacific Northwest, three-dimensional P- and S-wave velocity (VP and VS, respectively) models incorporating the Cascadia subduction zone were previously developed for the region encompassed from about 40.2°N. to 50°N. latitude, and from about 122°W. to 129°W. longitude. This report describes updates to the Cascadia velocit
Authors
William J. Stephenson, Nadine G. Reitman, Stephen J. Angster
3D ground‐motion simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone: Variability of long‐period (T≥1 s) ground motions and sensitivity to kinematic rupture parameters
We examine the variability of long‐period (T≥1 s) earthquake ground motions from 3D simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone, Utah, from a set of 96 rupture models with varying slip distributions, rupture speeds, slip velocities, and hypocenter locations. Earthquake ruptures were prescribed on a 3D fault representation that satisfies geologic constra
Authors
Morgan P. Moschetti, Stephen H. Hartzell, Leonardo Ramirez-Guzman, Arthur Frankel, Stephen J. Angster, William J. Stephenson
A paleoseismic transect across the northwestern Basin and Range Province, northwestern Nevada and northeastern California, USA
We use new and existing data to compile a record of ∼18 latest Quaternary large-magnitude surface-rupturing earthquakes on 7 fault zones in the northwestern Basin and Range Province of northwestern Nevada and northeastern California. The most recent earthquake on all faults postdates the ca. 18–15 ka last glacial highstand of pluvial Lake Lahontan and other pluvial lakes in the region. These lacus
Authors
Stephen Personius, Richard W. Briggs, J. Zebulon Maharrey, Stephen J. Angster, Shannon A. Mahan
Uplift and subsidence reveal a nonpersistent megathrust rupture boundary (Sitkinak Island, Alaska)
We report stratigraphic evidence of land-level change and tsunami inundation along the Alaska-Aleutian megathrust during prehistoric and historical earthquakes west of Kodiak Island. On Sitkinak Island, cores and tidal outcrops fringing a lagoon reveal five sharp lithologic contacts that record coseismic land-level change. Radiocarbon dates, 137Cs profiles, CT scans, and microfossil assemblages ar
Authors
Richard W. Briggs, Simon E. Engelhart, Alan R. Nelson, Tina Dura, Andrew C. Kemp, Peter J. Haeussler, D. Reide Corbett, Stephen J. Angster, Lee-Ann Bradley
Modeling of wave driven circulation and water quality in nearshore environments
In order to investigate the effects of nearshore discharges of water quality degrading substances and bacteria in coastal environments, models capable of predicting nearshore circulation due to local wave and tide conditions are required. One of the larger challenges to nearshore coastal modeling is accurately reproducing nearshore circulation due to wave action. Local wave action not only drives
Authors
Craig Jones, Stephen J. Angster
Non-USGS Publications**
Angster, S., Wesnousky, S., Figueiredo, P., Owen, L., and Hammer, S., 2019. Late Quaternary slip rates for faults of the central Walker Lane (Nevada, USA): Spatiotemporal strain release in a strike-slip fault system. Geosphere, 15(5), pp.1460-1478.
Angster, S., Wesnousky, S., Huang, W.L., Kent, G., Nakata, T. and Goto, H., 2016. Application of UAV photography to refining the slip rate on the Pyramid Lake fault zone, Nevada. Bulletin of the Seismological Society of America, 106(2), pp.785-798.
Angster, S., Fielding, E.J., Wesnousky, S., Pierce, I., Chamlagain, D., Gautam, D., Upreti, B., Kumahara, Y. and Nakata, T., 2015. Field reconnaissance after the 25 April 2015 M 7.8 Gorkha earthquake. Seismological Research Letters, 86(6), pp.1506-1513.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western U.S.) (ver. 3.0, December 2023)
This Data Release contains version 3.0 of two related earthquake geology databases for use in the 2023 U.S. National Seismic Hazard Model. The databases are: 1) A fault sections database (“NSHM23_FSD_v3”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) an earthquake geology site information database (“NSHM23_EQGeoDB_v3”), which contains fault slip rate cons
Data Release for Luminescence: Paleoseismic liquefaction associated with Holocene earthquakes on the Wallula Fault zone, Southeast Washington, USA
Observations of widespread liquefaction and stratigraphic and structural relationships in a trench across an ambiguous scarp are used to constrain the timing of Holocene earthquakes on the northwest-striking Wallula fault zone in southeast Washington and Oregon. Additional observations and age constraints from OSL analysis of samples collected from large-scale liquefaction features that crosscut t
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western US) (ver. 2.0, February 2022)
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ('NSHM23_FSD_v2'), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ('NSHM23_EQGeoDB_v2'), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of updates to the N
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023, version 1.0
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ("NSHM2023_FaultSections_v1"), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ("NSHM2023_EQGeoDB_v1"), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of up
2020 Update to the Quaternary Fault and Fold Database for Washington State
This release is an update to the online "Quaternary fault and fold database" for Washington State. The online database was last updated for Washington in 2014 – this 2020 update includes newly identified and modified traces and geometries for on-shore faults gleaned from new peer-reviewed studies and mapping of active faults within the state of Washington. These data contain lines representing the
Field observations and logs from the Rose Hip trench exposure across a north-facing scarp within the Seattle Fault Zone, southern Bainbridge Island, Washington
The Seattle Fault Zone is an approximately 70-km-long, east-west-trending zone of south-dipping blind reverse faults within the Puget lowland region in Washington. Because of the proximity, the Seattle Fault Zone poses a significant earthquake hazard to the Puget sound and Seattle metropolitan regions. We present preliminary mapping and trench-site information from a paleoseismic investigation acr
Logs and data from the Starthistle trench across a scarp within the Wallula Fault Zone, southeastern Washington
IntroductionThe Wallula Fault Zone is composed of a series of northwest-trending faults and folds that coincide with a prominent magnetic anomaly that extends uninterrupted for approximately 120 kilometers within the Cascadia back arc of southeastern Washington and northeastern Oregon. It is part of the geologic structures associated with the topographic lineament known as the Olympic-Wallowa line
Debris avalanches in the northern California Coast Range triggered by plate boundary earthquakes
Determining the timing and cause for ancient hillslope failures proves difficult in the western United States, yet critical as it ties directly into groundmotion estimates for hazardous events. This knowledge gap is important to confront as hillslope failures are candidates to be triggered by earthquakes along active plate boundaries. We identify two prehistoric, i.e., preinstrumental history, deb
Authors
Jessie K. Pearl, Harvey Kelsey, Stephen J. Angster, Dylan Caldwell, Ian Pryor, Brian Sherrod
Simplifying complex fault data for systems-level analysis: Earthquake geology inputs for U.S. NSHM 2023
As part of the U.S. National Seismic Hazard Model (NSHM) update planned for 2023, two databases were prepared to more completely represent Quaternary-active faulting across the western United States: the NSHM23 fault sections database (FSD) and earthquake geology database (EQGeoDB). In prior iterations of NSHM, fault sections were included only if a field-measurement-derived slip rate was estimate
Authors
Alexandra Elise Hatem, Camille Marie Collett, Richard W. Briggs, Ryan D. Gold, Stephen J. Angster, Ned Field, Peter M. Powers
Characterizing strain between rigid crustal blocks in the southern Cascadia forearc: Quaternary faults and folds of the northern Sacramento Valley, California
Topographic profiles across late Quaternary surfaces in the northern Sacramento Valley (California, USA) show offset and progressive folding on series of active east- and northeast—trending faults and folds. Optically stimulated luminescence ages on deposits draping a warped late Pleistocene river terrace yielded differential incision rates along the Sacramento River and indicate tectonic uplift e
Authors
Stephen J. Angster, Steven G. Wesnousky, Paula Figueiredo, Lewis A. Owen, Thomas Sawyer
Post-glacial Mw 7.0-7.5 earthquakes on the North Olympic fault zone, Washington
Holocene crustal faulting in the northern Olympic Peninsula of Washington State manifests in a zone of west‐northwest‐striking crustal faults herein named the North Olympic fault zone, which extends for ∼80 km∼80 km along strike and includes the Lake Creek–Boundary Creek fault to the east and the Sadie Creek fault and newly discovered scarps to the west. This study focuses on the Sadie Creek fau
Authors
Elizabeth R. Schermer, Colin B. Amos, W. Cody Duckworth, Alan Nelson, Stephen J. Angster, Jaime Delano, Brian Sherrod
Documentation of Surface Fault Rupture and Ground‐Deformation Features Produced by the 4 and 5 July 2019 Mw 6.4 and Mw 7.1 Ridgecrest Earthquake Sequence
The MwMw 6.4 and MwMw 7.1 Ridgecrest earthquake sequence occurred on 4 and 5 July 2019 within the eastern California shear zone of southern California. Both events produced extensive surface faulting and ground deformation within Indian Wells Valley and Searles Valley. In the weeks following the earthquakes, more than six dozen scientists from government, academia, and the private sector carefully
Authors
Daniel J. Ponti, James Luke Blair, Rosa Carla M, Kate Thomas, Alexandra Pickering, Sinan Akciz, Stephen J. Angster, Jean-Philipe Avouac, Jeffrey Bachhuber, Steven Bacon, Nicolas C. Barth, S. Bennett, Kelly Blake, Stephan Bork, Benjamin A. Brooks, Thomas Bullard, Paul A. Burgess, Colin Chupik, Timothy E. Dawson, Michael DeFrisco, Jaime E. Delano, Stephen B. DeLong, James D. Dolan, Andrea Donnellan, Christopher DuRoss, Todd Ericksen, Erik Frost, Gareth J. Funning, Ryan D. Gold, Nicholas A Graehl, Carlos Gutierrez, Elizabeth Haddon, Alexandra Elise Hatem, John Helms, Janis Hernandez, Christopher S. Hitchcock, Peter Holland, Kenneth W. Hudnut, Katherine J. Kendrick, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Robert Leeper, Christopher Madugo, Maxime Mareschal, James McDonald, Devin McPhillips, Christopher Milliner, Daniel Mongovin, Alexander Morelan, Stephanie Nale, Johanna Nevitt, Matt O'Neal, Brian J. Olsen, Michael Oskin, Salena Padilla, Jason Patton, Belle E. Philibosian, Ian Pierce, Cynthia Pridmore, Nathaniel Roth, David Sandwell, Katherine M. Scharer, Gordon G. Seitz, Drake Singleton, Bridget Smith-Konter, Eleanor Spangler, Brian J. Swanson, Jessica Thompson Jobe, Jerome Treiman, Francesca Valencia, Joshua Vanderwal, Alana Williams, Xiaohua Xu, Judith Zachariasen, Jade Zimmerman, Robert Zinke
Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures
Surface rupture in the 2019 Ridgecrest, California, earthquake sequence occurred along two orthogonal cross faults and includes dominantly left‐lateral and northeast‐striking rupture in the Mw 6.4 foreshock and dominantly right‐lateral and northwest‐striking rupture in the Mw 7.1 mainshock. We present >650 field‐based, surface‐displacement observations for these ruptures and synthesize our results
Authors
Christopher DuRoss, Ryan D. Gold, Timothy E. Dawson, Katherine M. Scharer, Katherine J. Kendrick, Sinan Akciz, Stephen J. Angster, Jeffery Bachhuber, Steven Bacon, Scott E.K. Bennett, Luke Blair, Benjamin A. Brooks, Thomas Bullard, W. Paul Burgess, Colin Chupik, Michael DeFrisco, Jaime Delano, James D. Dolan, Erik Frost, Nick Graehl, Elizabeth Haddon, Alexandra Elise Hatem, Janis Hernandez, Christopher S. Hitchcock, Kennth Hudnut, Jessica Thompson Jobe, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Christopher Madugo, Devin McPhillips, Christopher Milliner, Alexander Morelan, Brian Olson, Jason Patton, Belle E. Philibosian, Alexandra J. Pickering, Ian Pierce, Daniel J. Ponti, Gordon G. Seitz, Eleanor Spangler, Brian J. Swanson, Kate Thomas, Jerome Treiman, Francesca Valencia, Alana Williams, Robert Zinke
P- and S-wave velocity models incorporating the Cascadia subduction zone for 3D earthquake ground motion simulations, Version 1.6—Update for Open-File Report 2007–1348
In support of earthquake hazard studies and ground motion simulations in the Pacific Northwest, three-dimensional P- and S-wave velocity (VP and VS, respectively) models incorporating the Cascadia subduction zone were previously developed for the region encompassed from about 40.2°N. to 50°N. latitude, and from about 122°W. to 129°W. longitude. This report describes updates to the Cascadia velocit
Authors
William J. Stephenson, Nadine G. Reitman, Stephen J. Angster
3D ground‐motion simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone: Variability of long‐period (T≥1 s) ground motions and sensitivity to kinematic rupture parameters
We examine the variability of long‐period (T≥1 s) earthquake ground motions from 3D simulations of Mw 7 earthquakes on the Salt Lake City segment of the Wasatch fault zone, Utah, from a set of 96 rupture models with varying slip distributions, rupture speeds, slip velocities, and hypocenter locations. Earthquake ruptures were prescribed on a 3D fault representation that satisfies geologic constra
Authors
Morgan P. Moschetti, Stephen H. Hartzell, Leonardo Ramirez-Guzman, Arthur Frankel, Stephen J. Angster, William J. Stephenson
A paleoseismic transect across the northwestern Basin and Range Province, northwestern Nevada and northeastern California, USA
We use new and existing data to compile a record of ∼18 latest Quaternary large-magnitude surface-rupturing earthquakes on 7 fault zones in the northwestern Basin and Range Province of northwestern Nevada and northeastern California. The most recent earthquake on all faults postdates the ca. 18–15 ka last glacial highstand of pluvial Lake Lahontan and other pluvial lakes in the region. These lacus
Authors
Stephen Personius, Richard W. Briggs, J. Zebulon Maharrey, Stephen J. Angster, Shannon A. Mahan
Uplift and subsidence reveal a nonpersistent megathrust rupture boundary (Sitkinak Island, Alaska)
We report stratigraphic evidence of land-level change and tsunami inundation along the Alaska-Aleutian megathrust during prehistoric and historical earthquakes west of Kodiak Island. On Sitkinak Island, cores and tidal outcrops fringing a lagoon reveal five sharp lithologic contacts that record coseismic land-level change. Radiocarbon dates, 137Cs profiles, CT scans, and microfossil assemblages ar
Authors
Richard W. Briggs, Simon E. Engelhart, Alan R. Nelson, Tina Dura, Andrew C. Kemp, Peter J. Haeussler, D. Reide Corbett, Stephen J. Angster, Lee-Ann Bradley
Modeling of wave driven circulation and water quality in nearshore environments
In order to investigate the effects of nearshore discharges of water quality degrading substances and bacteria in coastal environments, models capable of predicting nearshore circulation due to local wave and tide conditions are required. One of the larger challenges to nearshore coastal modeling is accurately reproducing nearshore circulation due to wave action. Local wave action not only drives
Authors
Craig Jones, Stephen J. Angster
Non-USGS Publications**
Angster, S., Wesnousky, S., Figueiredo, P., Owen, L., and Hammer, S., 2019. Late Quaternary slip rates for faults of the central Walker Lane (Nevada, USA): Spatiotemporal strain release in a strike-slip fault system. Geosphere, 15(5), pp.1460-1478.
Angster, S., Wesnousky, S., Huang, W.L., Kent, G., Nakata, T. and Goto, H., 2016. Application of UAV photography to refining the slip rate on the Pyramid Lake fault zone, Nevada. Bulletin of the Seismological Society of America, 106(2), pp.785-798.
Angster, S., Fielding, E.J., Wesnousky, S., Pierce, I., Chamlagain, D., Gautam, D., Upreti, B., Kumahara, Y. and Nakata, T., 2015. Field reconnaissance after the 25 April 2015 M 7.8 Gorkha earthquake. Seismological Research Letters, 86(6), pp.1506-1513.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.