Kyle B Withers
Kyle Withers is a research geophysicist with the Earthquake Hazards Program.
Science and Products
Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview
This data release contains data sets associated with the 2023 50-State National Seismic Hazard Model Update. The 2023 50-State National Seimsic Hazard Model (NSHM) Update includes an update to the NSHMs for the conterminous U.S (CONUS, last updated in 2018), Alaska (AK, last updated in 2007), and Hawaii (last updated in 2001). Data sets include inputs like seismicity catalogs used as...
Filter Total Items: 17
2025 USGS National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands: Overview of model and hazard results 2025 USGS National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands: Overview of model and hazard results
The U.S. Geological Survey recently updated the National Seismic Hazard Model (NSHM) for Puerto Rico and the U.S. Virgin Islands (PRVI). The first version of the PRVI NSHM was released in 2003, and therefore this 2025 update includes over 20 years of new geologic, geophysical, and engineering data, methods, and models. Updates follow similar efforts performed in the recent 2023 50-state...
Authors
Allison M. Shumway, Kevin Ross Milner, Peter M. Powers, Morgan P. Moschetti, Jason M. Altekruse, Julie A. Herrick, Andrea L. Llenos, Kyle B. Withers, Edward H. Field, Brad T. Aagaard, Richard W. Briggs, Alexandra Elise Hatem, Kirstie Lafon Haynie, Andrew J. Michael, Jessica A. Thompson Jobe, Kishor S. Jaiswal, Brandon S. Clayton, Nico Luco, Mark D. Petersen, Sanaz Rezaeian, Thomas L. Pratt, Yuehua Zeng
Ground-motion characterization for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands Ground-motion characterization for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands
We develop the ground-motion characterization (GMC) for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands (NSHM-PRVI) for earthquakes in active crustal, subduction interface, and subduction intraslab regimes. Using ground-motion models (GMMs) from the Next-Generation Attenuation (NGA)-West2 and NGA-Subduction projects, the GMC is parameterized by...
Authors
Morgan P. Moschetti, Brad T. Aagaard, Kyle B. Withers, Kevin Ross Milner, Jason M. Altekruse, Julie A. Herrick, Peter M. Powers, Sanaz Rezaeian, Allison M. Shumway, William J. Stephenson
Suitability of ground-motion models for seismic hazard assessment in Puerto Rico and the U.S. Virgin Islands Suitability of ground-motion models for seismic hazard assessment in Puerto Rico and the U.S. Virgin Islands
We perform linear mixed-effects analyses with a ground-motion dataset to evaluate how well ground-motion models (GMMs) fit active crustal, subduction interface, and subduction intraslab earthquakes in Puerto Rico and the US Virgin Islands. Most of the GMMs reproduce the spatial variation in peak ground motions with earthquake magnitude and rupture distance but predict ground motions 0.3...
Authors
Brad T. Aagaard, Morgan P. Moschetti, Kyle B. Withers
The 2025 Puerto Rico and Virgin Islands U.S. National Seismic Hazard Model Update: Ground motion model selection and comparison The 2025 Puerto Rico and Virgin Islands U.S. National Seismic Hazard Model Update: Ground motion model selection and comparison
We evaluate, select, and describe the ground-motion models (GMMs) used in the 2025 update of the U.S. National Seismic Hazard Model (NSHM) for Puerto Rico and the U.S. Virgin Islands (PRVI). We identify the most appropriate models that align with GMM selection criteria for use in the PRVI region to improve the accuracy of seismic hazard assessments. The update incorporates globally...
Authors
Kyle B. Withers, Morgan P. Moschetti, Brad T. Aagaard, Peter M. Powers, Jason M. Altekruse, Sanaz Rezaeian
Methods to evaluate and improve the modeling of rupture directivity in assessment of seismic hazard Methods to evaluate and improve the modeling of rupture directivity in assessment of seismic hazard
In recent years, there have been several advancements related to the modelling of near-source effects of earthquake rupture on strong ground shaking, leading to an improved characterization of ground motions and resulting seismic hazard. Some of these modifications have stemmed from physics-based numerical modelling of the earthquake rupture process, using physics-based dynamic rupture...
Authors
Kyle B. Withers, Brian Kelly, Jeff Bayless, Morgan P. Moschetti
Framework for implementing damping scaling factors in U.S. Geological Survey National Seismic Hazard Models Framework for implementing damping scaling factors in U.S. Geological Survey National Seismic Hazard Models
Traditionally, probabilistic seismic hazard analysis (PSHA) has focused on calculating ground motion hazard curves for elastic, 5%-damped pseudo spectral accelerations, Sa(T,5%), which are used as the basis for engineering design parameters and targets for ground motion selection and modification. However, structures and geotechnical systems can exhibit a wide range of damping ratios...
Authors
Andrew James Makdisi, Dallin Smith, Sanaz Rezaeian, Peter M. Powers, Kyle B. Withers
The 2023 U.S. National Seismic Hazard Model: Subduction ground motion models The 2023 U.S. National Seismic Hazard Model: Subduction ground motion models
The US Geological Survey National Seismic Hazard Models (NSHMs) are used to calculate earthquake ground-shaking intensities for design and rehabilitation of structures in the United States. The most recent 2014 and 2018 versions of the NSHM for the conterminous United States included major updates to ground-motion models (GMMs) for active and stable crustal tectonic settings; however...
Authors
Sanaz Rezaeian, Peter M. Powers, Jason M. Altekruse, Sean Kamran Ahdi, Mark D. Petersen, Allison M. Shumway, Arthur D. Frankel, Erin A. Wirth, James Andrew Smith, Morgan P. Moschetti, Kyle B. Withers, Julie A. Herrick
Basin effects from 3D simulated ground motions in the Greater Los Angeles region for use in seismic-hazard analyses Basin effects from 3D simulated ground motions in the Greater Los Angeles region for use in seismic-hazard analyses
We develop basin-depth-scaling models (i.e. “basin terms”) from the long-period (T≥2s) simulated ground motions of the Southern California Earthquake Center (SCEC) CyberShake project for use in seismic hazard analyses at sites within the sedimentary basins of southern California. Basin terms use the Next Generation Attenuation (NGA)-West-2 ground-motion models (GMMs) as reference...
Authors
Morgan P. Moschetti, Eric M. Thompson, Kyle B. Withers
Integration of rupture directivity models for the US National Seismic Hazard Model Integration of rupture directivity models for the US National Seismic Hazard Model
Several rupture directivity models (DMs) have been developed in recent years to describe the near-source spatial variations in ground motion amplitudes related to propagation of rupture along the fault. We recently organized an effort towards incorporating these directivity effects into the USGS National Seismic Hazard Model (NSHM), by first evaluating the community's work and potential...
Authors
Kyle B. Withers, Morgan P. Moschetti, Peter M. Powers, Mark D. Petersen, Robert Graves, Brad T. Aagaard, Annemarie S. Baltay, Nico Luco, Erin A. Wirth, Sanaz Rezaeian, Eric M. Thompson
The 2023 US National Seismic Hazard Model: Ground-motion characterization for the conterminous United States The 2023 US National Seismic Hazard Model: Ground-motion characterization for the conterminous United States
We update the ground-motion characterization for the 2023 National Seismic Hazard Model (NSHM) for the conterminous United States. The update includes the use of new ground-motion models (GMMs) in the Cascadia subduction zone; an adjustment to the central and eastern United States (CEUS) GMMs to reduce misfits with observed data; an updated boundary for the application of GMMs for...
Authors
Morgan P. Moschetti, Brad T. Aagaard, Sean Kamran Ahdi, Jason M. Altekruse, Oliver S. Boyd, Arthur D. Frankel, Julie A. Herrick, Mark D. Petersen, Peter M. Powers, Sanaz Rezaeian, Allison M. Shumway, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Kyle B. Withers
The 2023 US 50-State National Seismic Hazard Model: Overview and implications The 2023 US 50-State National Seismic Hazard Model: Overview and implications
The US National Seismic Hazard Model (NSHM) was updated in 2023 for all 50 states using new science on seismicity, fault ruptures, ground motions, and probabilistic techniques to produce a standard of practice for public policy and other engineering applications (defined for return periods greater than ∼475 or less than ∼10,000 years). Changes in 2023 time-independent seismic hazard...
Authors
Mark D. Petersen, Allison M. Shumway, Peter M. Powers, Edward H. Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur D. Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle B. Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nico Luco, Kenneth S. Rukstales, Julie A. Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael L. Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon S. Clayton, Christopher B. DuRoss, Eileen L. Evans, Peter J. Haeussler, Alexandra Elise Hatem, Kirstie Lafon Haynie, Elizabeth H. Hearn, Kaj M. Johnson, Zachary Alan Kortum, N. Simon Kwong, Andrew James Makdisi, Henry Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Frederick Pollitz, Justin L. Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica A. Thompson Jobe, Erin A. Wirth, Robert C. Witter
Automated detection of clipping in broadband earthquake records Automated detection of clipping in broadband earthquake records
Because the amount of available ground‐motion data has increased over the last decades, the need for automated processing algorithms has also increased. One difficulty with automated processing is to screen clipped records. Clipping occurs when the ground‐motion amplitude exceeds the dynamic range of the linear response of the instrument. Clipped records in which the amplitude exceeds...
Authors
James Kael Kleckner, Kyle B. Withers, Eric M. Thompson, J.M. Rekoske, Emily Wolin, Morgan P. Moschetti
Science and Products
Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview
This data release contains data sets associated with the 2023 50-State National Seismic Hazard Model Update. The 2023 50-State National Seimsic Hazard Model (NSHM) Update includes an update to the NSHMs for the conterminous U.S (CONUS, last updated in 2018), Alaska (AK, last updated in 2007), and Hawaii (last updated in 2001). Data sets include inputs like seismicity catalogs used as...
Filter Total Items: 17
2025 USGS National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands: Overview of model and hazard results 2025 USGS National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands: Overview of model and hazard results
The U.S. Geological Survey recently updated the National Seismic Hazard Model (NSHM) for Puerto Rico and the U.S. Virgin Islands (PRVI). The first version of the PRVI NSHM was released in 2003, and therefore this 2025 update includes over 20 years of new geologic, geophysical, and engineering data, methods, and models. Updates follow similar efforts performed in the recent 2023 50-state...
Authors
Allison M. Shumway, Kevin Ross Milner, Peter M. Powers, Morgan P. Moschetti, Jason M. Altekruse, Julie A. Herrick, Andrea L. Llenos, Kyle B. Withers, Edward H. Field, Brad T. Aagaard, Richard W. Briggs, Alexandra Elise Hatem, Kirstie Lafon Haynie, Andrew J. Michael, Jessica A. Thompson Jobe, Kishor S. Jaiswal, Brandon S. Clayton, Nico Luco, Mark D. Petersen, Sanaz Rezaeian, Thomas L. Pratt, Yuehua Zeng
Ground-motion characterization for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands Ground-motion characterization for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands
We develop the ground-motion characterization (GMC) for the 2025 U.S. National Seismic Hazard Model for Puerto Rico and the U.S. Virgin Islands (NSHM-PRVI) for earthquakes in active crustal, subduction interface, and subduction intraslab regimes. Using ground-motion models (GMMs) from the Next-Generation Attenuation (NGA)-West2 and NGA-Subduction projects, the GMC is parameterized by...
Authors
Morgan P. Moschetti, Brad T. Aagaard, Kyle B. Withers, Kevin Ross Milner, Jason M. Altekruse, Julie A. Herrick, Peter M. Powers, Sanaz Rezaeian, Allison M. Shumway, William J. Stephenson
Suitability of ground-motion models for seismic hazard assessment in Puerto Rico and the U.S. Virgin Islands Suitability of ground-motion models for seismic hazard assessment in Puerto Rico and the U.S. Virgin Islands
We perform linear mixed-effects analyses with a ground-motion dataset to evaluate how well ground-motion models (GMMs) fit active crustal, subduction interface, and subduction intraslab earthquakes in Puerto Rico and the US Virgin Islands. Most of the GMMs reproduce the spatial variation in peak ground motions with earthquake magnitude and rupture distance but predict ground motions 0.3...
Authors
Brad T. Aagaard, Morgan P. Moschetti, Kyle B. Withers
The 2025 Puerto Rico and Virgin Islands U.S. National Seismic Hazard Model Update: Ground motion model selection and comparison The 2025 Puerto Rico and Virgin Islands U.S. National Seismic Hazard Model Update: Ground motion model selection and comparison
We evaluate, select, and describe the ground-motion models (GMMs) used in the 2025 update of the U.S. National Seismic Hazard Model (NSHM) for Puerto Rico and the U.S. Virgin Islands (PRVI). We identify the most appropriate models that align with GMM selection criteria for use in the PRVI region to improve the accuracy of seismic hazard assessments. The update incorporates globally...
Authors
Kyle B. Withers, Morgan P. Moschetti, Brad T. Aagaard, Peter M. Powers, Jason M. Altekruse, Sanaz Rezaeian
Methods to evaluate and improve the modeling of rupture directivity in assessment of seismic hazard Methods to evaluate and improve the modeling of rupture directivity in assessment of seismic hazard
In recent years, there have been several advancements related to the modelling of near-source effects of earthquake rupture on strong ground shaking, leading to an improved characterization of ground motions and resulting seismic hazard. Some of these modifications have stemmed from physics-based numerical modelling of the earthquake rupture process, using physics-based dynamic rupture...
Authors
Kyle B. Withers, Brian Kelly, Jeff Bayless, Morgan P. Moschetti
Framework for implementing damping scaling factors in U.S. Geological Survey National Seismic Hazard Models Framework for implementing damping scaling factors in U.S. Geological Survey National Seismic Hazard Models
Traditionally, probabilistic seismic hazard analysis (PSHA) has focused on calculating ground motion hazard curves for elastic, 5%-damped pseudo spectral accelerations, Sa(T,5%), which are used as the basis for engineering design parameters and targets for ground motion selection and modification. However, structures and geotechnical systems can exhibit a wide range of damping ratios...
Authors
Andrew James Makdisi, Dallin Smith, Sanaz Rezaeian, Peter M. Powers, Kyle B. Withers
The 2023 U.S. National Seismic Hazard Model: Subduction ground motion models The 2023 U.S. National Seismic Hazard Model: Subduction ground motion models
The US Geological Survey National Seismic Hazard Models (NSHMs) are used to calculate earthquake ground-shaking intensities for design and rehabilitation of structures in the United States. The most recent 2014 and 2018 versions of the NSHM for the conterminous United States included major updates to ground-motion models (GMMs) for active and stable crustal tectonic settings; however...
Authors
Sanaz Rezaeian, Peter M. Powers, Jason M. Altekruse, Sean Kamran Ahdi, Mark D. Petersen, Allison M. Shumway, Arthur D. Frankel, Erin A. Wirth, James Andrew Smith, Morgan P. Moschetti, Kyle B. Withers, Julie A. Herrick
Basin effects from 3D simulated ground motions in the Greater Los Angeles region for use in seismic-hazard analyses Basin effects from 3D simulated ground motions in the Greater Los Angeles region for use in seismic-hazard analyses
We develop basin-depth-scaling models (i.e. “basin terms”) from the long-period (T≥2s) simulated ground motions of the Southern California Earthquake Center (SCEC) CyberShake project for use in seismic hazard analyses at sites within the sedimentary basins of southern California. Basin terms use the Next Generation Attenuation (NGA)-West-2 ground-motion models (GMMs) as reference...
Authors
Morgan P. Moschetti, Eric M. Thompson, Kyle B. Withers
Integration of rupture directivity models for the US National Seismic Hazard Model Integration of rupture directivity models for the US National Seismic Hazard Model
Several rupture directivity models (DMs) have been developed in recent years to describe the near-source spatial variations in ground motion amplitudes related to propagation of rupture along the fault. We recently organized an effort towards incorporating these directivity effects into the USGS National Seismic Hazard Model (NSHM), by first evaluating the community's work and potential...
Authors
Kyle B. Withers, Morgan P. Moschetti, Peter M. Powers, Mark D. Petersen, Robert Graves, Brad T. Aagaard, Annemarie S. Baltay, Nico Luco, Erin A. Wirth, Sanaz Rezaeian, Eric M. Thompson
The 2023 US National Seismic Hazard Model: Ground-motion characterization for the conterminous United States The 2023 US National Seismic Hazard Model: Ground-motion characterization for the conterminous United States
We update the ground-motion characterization for the 2023 National Seismic Hazard Model (NSHM) for the conterminous United States. The update includes the use of new ground-motion models (GMMs) in the Cascadia subduction zone; an adjustment to the central and eastern United States (CEUS) GMMs to reduce misfits with observed data; an updated boundary for the application of GMMs for...
Authors
Morgan P. Moschetti, Brad T. Aagaard, Sean Kamran Ahdi, Jason M. Altekruse, Oliver S. Boyd, Arthur D. Frankel, Julie A. Herrick, Mark D. Petersen, Peter M. Powers, Sanaz Rezaeian, Allison M. Shumway, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Kyle B. Withers
The 2023 US 50-State National Seismic Hazard Model: Overview and implications The 2023 US 50-State National Seismic Hazard Model: Overview and implications
The US National Seismic Hazard Model (NSHM) was updated in 2023 for all 50 states using new science on seismicity, fault ruptures, ground motions, and probabilistic techniques to produce a standard of practice for public policy and other engineering applications (defined for return periods greater than ∼475 or less than ∼10,000 years). Changes in 2023 time-independent seismic hazard...
Authors
Mark D. Petersen, Allison M. Shumway, Peter M. Powers, Edward H. Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur D. Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle B. Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nico Luco, Kenneth S. Rukstales, Julie A. Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael L. Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon S. Clayton, Christopher B. DuRoss, Eileen L. Evans, Peter J. Haeussler, Alexandra Elise Hatem, Kirstie Lafon Haynie, Elizabeth H. Hearn, Kaj M. Johnson, Zachary Alan Kortum, N. Simon Kwong, Andrew James Makdisi, Henry Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Frederick Pollitz, Justin L. Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica A. Thompson Jobe, Erin A. Wirth, Robert C. Witter
Automated detection of clipping in broadband earthquake records Automated detection of clipping in broadband earthquake records
Because the amount of available ground‐motion data has increased over the last decades, the need for automated processing algorithms has also increased. One difficulty with automated processing is to screen clipped records. Clipping occurs when the ground‐motion amplitude exceeds the dynamic range of the linear response of the instrument. Clipped records in which the amplitude exceeds...
Authors
James Kael Kleckner, Kyle B. Withers, Eric M. Thompson, J.M. Rekoske, Emily Wolin, Morgan P. Moschetti