I am a research and development geophysicist specializing in probabilisitic seismic hazard analysis.
Science and Products
Operational Earthquake Forecasting – Implementing a Real-Time System for California
It is well know that every earthquake can spawn others (e.g., as aftershocks), and that such triggered events can be large and damaging, as recently demonstrated by L’Aquila, Italy and Christchurch, New Zealand earthquakes. In spite of being an explicit USGS strategic-action priority (http://pubs.usgs.gov/of/2012/1088; page 32), the USGS currently lacks an automated system with which to forecast s...
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
Data Release for PGV Data for the 2018 National Seismic Hazard Model for the Conterminous United States
Peak ground velocity (PGV) gridded probabilistic seismic hazard data for the updated 2018 National Seismic Hazard Model (NSHM) for the Conterminous United States (CONUS). PGV hazard curves and ground motions have been calculated on a 0.05 by 0.05 degree grid using the NSHM CONUS 2018 earthquake source model. PGV support has been incorporated into the NSHM using a newly developed PGV model conditio
Geologic Inputs for the 2023 Alaska Update to the U.S. National Seismic Hazard Model (NSHM)
This data release is composed of three crustal (as opposed to subduction zone) geologic input datasets for the 2023 Alaska update to the U.S. National Seismic Hazard Model (NSHM): 1) fault section vector line data, 2) fault zone vector polygon data, and 3) accompanying earthquake geology attributes.
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
Shakemap earthquake scenario: Building Seismic Safety Council 2014 Event Set (BSSC2014)
This is a catalog of earthquake scenarios, represented as ShakeMaps. A ShakeMap is a USGS product that facilitates communication of earthquake effects by portraying a map of the severity of shaking. Maps of shaking severity are provided in terms of macroseismic intensity, peak ground acceleration, peak ground velocity, and spectral accelerations (at 0.3, 1.0 and 3 sec oscillator periods).
Filter Total Items: 22
Magnitude conversion and earthquake recurrence rate models for the central and eastern United States
Development of Seismic Source Characterization (SSC) models, which is an essential part of Probabilistic Seismic Hazard Analyses (PSHA), can help forecast the temporal and spatial distribution of future damaging earthquakes (𝑀w≥ 5) in seismically active regions. Because it is impossible to associate all earthquakes with known faults, seismic source models for PSHA often include sources of diffuse
Authors
Rasool Anooshehpoor, Thomas Weaver, Jon Ake, Cliff Munson, Morgan P. Moschetti, David R. Shelly, Peter M. Powers
Western U.S. deformation models for the 2023 update to the U.S. National Seismic Hazard Model
This report describes geodetic and geologic information used to constrain deformation models of the 2023 update to the National Seismic Hazard Model (NSHM), a set of deformation models to interpret these data, and their implications for earthquake rates in the western United States. Recent updates provide a much larger data set of Global Positioning System crustal velocities than used in the 2014
Authors
Fred Pollitz, Eileen L. Evans, Edward H. Field, Alexandra Elise Hatem, Elizabeth H. Hearn, Kaj M Johnson, Jessica R. Murray, Peter M. Powers, Zheng-Kang Shen, Crystal Wespestad, Yuehua Zeng
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, Edward H. Field, Peter M. Powers
2021 U.S. National Seismic Hazard Model for the State of Hawaii
The 2021 U.S. National Seismic Hazard Model (NSHM) for the State of Hawaii updates the two-decades-old former model by incorporating new data and modeling techniques to improve the underlying ground shaking forecasts of tectonic-fault, tectonic-flexure, volcanic, and caldera collapse earthquakes. Two earthquake ground shaking hazard models (public policy and research) are produced that differ in h
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Morgan P. Moschetti, Andrea L. Llenos, Andrew J. Michael, Charles Mueller, Arthur Frankel, Sanaz Rezaeian, Kenneth S. Rukstales, Daniel E. McNamara, P. Okubo, Yuehua Zeng, Kishor Jaiswal, Sean Kamran Ahdi, Jason M. Altekruse, Brian Shiro
The 2018 update of the US National Seismic Hazard Model: Ground motion models in the western US
The U.S. Geological Survey (USGS) National Seismic Hazard Model (NSHM) is the scientific foundation of seismic design regulations in the United States and is regularly updated to consider the best available science and data. The 2018 update of the conterminous U.S. NSHM includes significant changes to the underlying ground motion models (GMMs), most of which are necessary to enable the new multi-p
Authors
Peter M. Powers, Sanaz Rezaeian, Allison Shumway, Mark D. Petersen, Nicolas Luco, Oliver S. Boyd, Morgan P. Moschetti, Arthur Frankel, Eric M. Thompson
The 2018 update of the US National Seismic Hazard Model: Ground motion models in the central and eastern US
The United States Geological Survey (USGS) National Seismic Hazard Model (NSHM) is the scientific foundation of seismic design regulations in the United States and is regularly updated to consider the best available science and data. The 2018 update of the conterminous US NSHM includes major changes to the underlying ground motion models (GMMs). Most of the changes are motivated by the new multi-p
Authors
Sanaz Rezaeian, Peter M. Powers, Allison Shumway, Mark D. Petersen, Nicolas Luco, Arthur Frankel, Morgan P. Moschetti, Eric M. Thompson, Daniel McNamara
The 2018 update of the US National Seismic Hazard Model: Where, why, and how much probabilistic ground motion maps changed
The 2018 US Geological Survey National Seismic Hazard Model (NSHM) incorporates new data and updated science to improve the underlying earthquake and ground motion forecasts for the conterminous United States. The NSHM considers many new data and component input models: (1) new earthquakes between 2013 and 2017 and updated earthquake magnitudes for some earlier earthquakes; (2) two updated smoothe
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Charles S Mueller, Morgan P. Moschetti, Arthur Frankel, Sanaz Rezaeian, Daniel McNamara, Nicolas Luco, Oliver S. Boyd, Kenneth S. Rukstales, Kishor Jaiswal, Eric M. Thompson, Susan M. Hoover, Brandon Clayton, Edward H. Field, Yuehua Zeng
The 2018 update of the US National Seismic Hazard Model: Additional period and site class data
As part of the update of the 2018 National Seismic Hazard Model (NSHM) for the conterminous United States (CONUS), new ground motion and site effect models for the central and eastern United States were incorporated, as well as basin depths from local seismic velocity models in four western US (WUS) urban areas. These additions allow us, for the first time, to calculate probabilistic seismic hazar
Authors
Allison Shumway, Mark D. Petersen, Peter M. Powers, Sanaz Rezaeian, Kenneth S. Rukstales, Brandon Clayton
Evaluation of ground‐motion models for U.S. Geological Survey seismic hazard forecasts: Hawaii tectonic earthquakes and volcanic eruptions
The selection and weighting of ground‐motion models (GMMs) introduces a significant source of uncertainty in U.S. Geological Survey (USGS) National Seismic Hazard Modeling Project (NSHMP) forecasts. In this study, we evaluate 18 candidate GMMs using instrumental ground‐motion observations of horizontal peak ground acceleration (PGA) and 5%‐damped pseudospectral acceleration (0.02–10 s) for tectoni
Authors
Daniel E. McNamara, Emily Wolin, Peter M. Powers, Allison Shumway, Morgan P. Moschetti, John Rekoske, Eric M. Thompson, Charles Mueller, Mark D. Petersen
Evaluation of ground‐motion models for U.S. Geological Survey seismic hazard models: 2018 Anchorage, Alaska, Mw 7.1 subduction zone earthquake sequence
Instrumental ground‐motion recordings from the 2018 Anchorage, Alaska (Mw 7.1), earthquake sequence provide an independent data set allowing us to evaluate the predictive power of ground‐motion models (GMMs) for intraslab earthquakes associated with the Alaska subduction zone. In this study, we evaluate 15 candidate GMMs using instrumental ground‐motion observations of peak ground acceleration an
Authors
Daniel E. McNamara, Emily Wolin, Peter M. Powers, Allison Shumway, Morgan P. Moschetti, John Rekoske, Eric M. Thompson, Charles Mueller, Mark D. Petersen
The 2018 update of the US National Seismic Hazard Model: Overview of model and implications
During 2017–2018, the National Seismic Hazard Model for the conterminous United States was updated as follows: (1) an updated seismicity catalog was incorporated, which includes new earthquakes that occurred from 2013 to 2017; (2) in the central and eastern United States (CEUS), new ground motion models were updated that incorporate updated median estimates, modified assessments of the associated
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Charles Mueller, Morgan P. Moschetti, Arthur Frankel, Sanaz Rezaeian, Daniel E. McNamara, Nicolas Luco, Oliver S. Boyd, Kenneth S. Rukstales, Kishor Jaiswal, Eric M. Thompson, Susan M. Hoover, Brandon Clayton, Edward H. Field, Yuehua Zeng
Ground-motion amplification in Cook Inlet region, Alaska from intermediate-depth earthquakes, including the 2018 MW=7.1 Anchorage earthquake
We measure pseudospectral and peak ground motions from 44 intermediate‐depth Mw≥4.9 earthquakes in the Cook Inlet region of southern Alaska, including those from the 2018 Mw 7.1 earthquake near Anchorage, to identify regional amplification features (0.1–5 s period). Ground‐motion residuals are computed with respect to an empirical ground‐motion model for intraslab subduction earthquakes, and we
Authors
Morgan P. Moschetti, Eric M. Thompson, John Rekoske, Mike Hearne, Peter M. Powers, Daniel E. McNamara, Carl Tape
Unified Hazard Tool
Use this web application to obtain earthquake hazards data from the U.S. Hazard Model.
nshm-hawaii-v2
National Seismic Hazard Model (NSHM) for the State of Hawaii. This model is intended for use with U.S. Geological Survey (USGS) hazard software nshmp-haz.
nshm-conus-v5
National Seismic Hazard Model (NSHM) for the conterminous U.S. This model is intended for use with U.S. Geological Survey (USGS) hazard software nshmp-haz. This model was last updated in 2018.
nshmp-haz-v2
U.S. Geological Survey (USGS) National Seismic Hazard Model Project (NSHMP) codes for performing probabilistic seismic hazard (PSHA) and related analyses. These codes are intended for use with seismic hazard models developed by the NSHMP for the U.S. and its territories. This project includes a variety of command line applications and web service classes and relies on the nshmp-lib hazard library,
nshmp-lib
nshmp-lib is a USGS developed Java library that supports probabilistic seismic hazard (PSHA) and related analyses. This project includes all the code required to load, process and query USGS National Seismic Hazard Models (NSHMs). nshmp-lib is used by command line applications and web services found in the nshmp-haz project. See that project for running PSHA calculations.
nshm-fault-sections
A repository of all geologic fault section data included in USGS National Seismic Hazard Models
nshmp-haz-v1
U.S. Geological Survey (USGS) National Seismic Hazard Mapping Project (NSHMP) code for performing probabilistic seismic hazard (PSHA) and related analyses. These codes are intended for use with seismic hazard models developed by the NSHMP for the U.S. and its territories.
Science and Products
- Science
Operational Earthquake Forecasting – Implementing a Real-Time System for California
It is well know that every earthquake can spawn others (e.g., as aftershocks), and that such triggered events can be large and damaging, as recently demonstrated by L’Aquila, Italy and Christchurch, New Zealand earthquakes. In spite of being an explicit USGS strategic-action priority (http://pubs.usgs.gov/of/2012/1088; page 32), the USGS currently lacks an automated system with which to forecast s... - Data
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 NData Release for PGV Data for the 2018 National Seismic Hazard Model for the Conterminous United States
Peak ground velocity (PGV) gridded probabilistic seismic hazard data for the updated 2018 National Seismic Hazard Model (NSHM) for the Conterminous United States (CONUS). PGV hazard curves and ground motions have been calculated on a 0.05 by 0.05 degree grid using the NSHM CONUS 2018 earthquake source model. PGV support has been incorporated into the NSHM using a newly developed PGV model conditioGeologic Inputs for the 2023 Alaska Update to the U.S. National Seismic Hazard Model (NSHM)
This data release is composed of three crustal (as opposed to subduction zone) geologic input datasets for the 2023 Alaska update to the U.S. National Seismic Hazard Model (NSHM): 1) fault section vector line data, 2) fault zone vector polygon data, and 3) accompanying earthquake geology attributes.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 upShakemap earthquake scenario: Building Seismic Safety Council 2014 Event Set (BSSC2014)
This is a catalog of earthquake scenarios, represented as ShakeMaps. A ShakeMap is a USGS product that facilitates communication of earthquake effects by portraying a map of the severity of shaking. Maps of shaking severity are provided in terms of macroseismic intensity, peak ground acceleration, peak ground velocity, and spectral accelerations (at 0.3, 1.0 and 3 sec oscillator periods). - Publications
Filter Total Items: 22
Magnitude conversion and earthquake recurrence rate models for the central and eastern United States
Development of Seismic Source Characterization (SSC) models, which is an essential part of Probabilistic Seismic Hazard Analyses (PSHA), can help forecast the temporal and spatial distribution of future damaging earthquakes (𝑀w≥ 5) in seismically active regions. Because it is impossible to associate all earthquakes with known faults, seismic source models for PSHA often include sources of diffuseAuthorsRasool Anooshehpoor, Thomas Weaver, Jon Ake, Cliff Munson, Morgan P. Moschetti, David R. Shelly, Peter M. PowersWestern U.S. deformation models for the 2023 update to the U.S. National Seismic Hazard Model
This report describes geodetic and geologic information used to constrain deformation models of the 2023 update to the National Seismic Hazard Model (NSHM), a set of deformation models to interpret these data, and their implications for earthquake rates in the western United States. Recent updates provide a much larger data set of Global Positioning System crustal velocities than used in the 2014AuthorsFred Pollitz, Eileen L. Evans, Edward H. Field, Alexandra Elise Hatem, Elizabeth H. Hearn, Kaj M Johnson, Jessica R. Murray, Peter M. Powers, Zheng-Kang Shen, Crystal Wespestad, Yuehua ZengSimplifying 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 estimateAuthorsAlexandra Elise Hatem, Camille Marie Collett, Richard W. Briggs, Ryan D. Gold, Stephen J. Angster, Edward H. Field, Peter M. Powers2021 U.S. National Seismic Hazard Model for the State of Hawaii
The 2021 U.S. National Seismic Hazard Model (NSHM) for the State of Hawaii updates the two-decades-old former model by incorporating new data and modeling techniques to improve the underlying ground shaking forecasts of tectonic-fault, tectonic-flexure, volcanic, and caldera collapse earthquakes. Two earthquake ground shaking hazard models (public policy and research) are produced that differ in hAuthorsMark D. Petersen, Allison Shumway, Peter M. Powers, Morgan P. Moschetti, Andrea L. Llenos, Andrew J. Michael, Charles Mueller, Arthur Frankel, Sanaz Rezaeian, Kenneth S. Rukstales, Daniel E. McNamara, P. Okubo, Yuehua Zeng, Kishor Jaiswal, Sean Kamran Ahdi, Jason M. Altekruse, Brian ShiroThe 2018 update of the US National Seismic Hazard Model: Ground motion models in the western US
The U.S. Geological Survey (USGS) National Seismic Hazard Model (NSHM) is the scientific foundation of seismic design regulations in the United States and is regularly updated to consider the best available science and data. The 2018 update of the conterminous U.S. NSHM includes significant changes to the underlying ground motion models (GMMs), most of which are necessary to enable the new multi-pAuthorsPeter M. Powers, Sanaz Rezaeian, Allison Shumway, Mark D. Petersen, Nicolas Luco, Oliver S. Boyd, Morgan P. Moschetti, Arthur Frankel, Eric M. ThompsonThe 2018 update of the US National Seismic Hazard Model: Ground motion models in the central and eastern US
The United States Geological Survey (USGS) National Seismic Hazard Model (NSHM) is the scientific foundation of seismic design regulations in the United States and is regularly updated to consider the best available science and data. The 2018 update of the conterminous US NSHM includes major changes to the underlying ground motion models (GMMs). Most of the changes are motivated by the new multi-pAuthorsSanaz Rezaeian, Peter M. Powers, Allison Shumway, Mark D. Petersen, Nicolas Luco, Arthur Frankel, Morgan P. Moschetti, Eric M. Thompson, Daniel McNamaraThe 2018 update of the US National Seismic Hazard Model: Where, why, and how much probabilistic ground motion maps changed
The 2018 US Geological Survey National Seismic Hazard Model (NSHM) incorporates new data and updated science to improve the underlying earthquake and ground motion forecasts for the conterminous United States. The NSHM considers many new data and component input models: (1) new earthquakes between 2013 and 2017 and updated earthquake magnitudes for some earlier earthquakes; (2) two updated smootheAuthorsMark D. Petersen, Allison Shumway, Peter M. Powers, Charles S Mueller, Morgan P. Moschetti, Arthur Frankel, Sanaz Rezaeian, Daniel McNamara, Nicolas Luco, Oliver S. Boyd, Kenneth S. Rukstales, Kishor Jaiswal, Eric M. Thompson, Susan M. Hoover, Brandon Clayton, Edward H. Field, Yuehua ZengThe 2018 update of the US National Seismic Hazard Model: Additional period and site class data
As part of the update of the 2018 National Seismic Hazard Model (NSHM) for the conterminous United States (CONUS), new ground motion and site effect models for the central and eastern United States were incorporated, as well as basin depths from local seismic velocity models in four western US (WUS) urban areas. These additions allow us, for the first time, to calculate probabilistic seismic hazarAuthorsAllison Shumway, Mark D. Petersen, Peter M. Powers, Sanaz Rezaeian, Kenneth S. Rukstales, Brandon ClaytonEvaluation of ground‐motion models for U.S. Geological Survey seismic hazard forecasts: Hawaii tectonic earthquakes and volcanic eruptions
The selection and weighting of ground‐motion models (GMMs) introduces a significant source of uncertainty in U.S. Geological Survey (USGS) National Seismic Hazard Modeling Project (NSHMP) forecasts. In this study, we evaluate 18 candidate GMMs using instrumental ground‐motion observations of horizontal peak ground acceleration (PGA) and 5%‐damped pseudospectral acceleration (0.02–10 s) for tectoniAuthorsDaniel E. McNamara, Emily Wolin, Peter M. Powers, Allison Shumway, Morgan P. Moschetti, John Rekoske, Eric M. Thompson, Charles Mueller, Mark D. PetersenEvaluation of ground‐motion models for U.S. Geological Survey seismic hazard models: 2018 Anchorage, Alaska, Mw 7.1 subduction zone earthquake sequence
Instrumental ground‐motion recordings from the 2018 Anchorage, Alaska (Mw 7.1), earthquake sequence provide an independent data set allowing us to evaluate the predictive power of ground‐motion models (GMMs) for intraslab earthquakes associated with the Alaska subduction zone. In this study, we evaluate 15 candidate GMMs using instrumental ground‐motion observations of peak ground acceleration anAuthorsDaniel E. McNamara, Emily Wolin, Peter M. Powers, Allison Shumway, Morgan P. Moschetti, John Rekoske, Eric M. Thompson, Charles Mueller, Mark D. PetersenThe 2018 update of the US National Seismic Hazard Model: Overview of model and implications
During 2017–2018, the National Seismic Hazard Model for the conterminous United States was updated as follows: (1) an updated seismicity catalog was incorporated, which includes new earthquakes that occurred from 2013 to 2017; (2) in the central and eastern United States (CEUS), new ground motion models were updated that incorporate updated median estimates, modified assessments of the associatedAuthorsMark D. Petersen, Allison Shumway, Peter M. Powers, Charles Mueller, Morgan P. Moschetti, Arthur Frankel, Sanaz Rezaeian, Daniel E. McNamara, Nicolas Luco, Oliver S. Boyd, Kenneth S. Rukstales, Kishor Jaiswal, Eric M. Thompson, Susan M. Hoover, Brandon Clayton, Edward H. Field, Yuehua ZengGround-motion amplification in Cook Inlet region, Alaska from intermediate-depth earthquakes, including the 2018 MW=7.1 Anchorage earthquake
We measure pseudospectral and peak ground motions from 44 intermediate‐depth Mw≥4.9 earthquakes in the Cook Inlet region of southern Alaska, including those from the 2018 Mw 7.1 earthquake near Anchorage, to identify regional amplification features (0.1–5 s period). Ground‐motion residuals are computed with respect to an empirical ground‐motion model for intraslab subduction earthquakes, and weAuthorsMorgan P. Moschetti, Eric M. Thompson, John Rekoske, Mike Hearne, Peter M. Powers, Daniel E. McNamara, Carl Tape - Web Tools
Unified Hazard Tool
Use this web application to obtain earthquake hazards data from the U.S. Hazard Model.
- Software
nshm-hawaii-v2
National Seismic Hazard Model (NSHM) for the State of Hawaii. This model is intended for use with U.S. Geological Survey (USGS) hazard software nshmp-haz.nshm-conus-v5
National Seismic Hazard Model (NSHM) for the conterminous U.S. This model is intended for use with U.S. Geological Survey (USGS) hazard software nshmp-haz. This model was last updated in 2018.nshmp-haz-v2
U.S. Geological Survey (USGS) National Seismic Hazard Model Project (NSHMP) codes for performing probabilistic seismic hazard (PSHA) and related analyses. These codes are intended for use with seismic hazard models developed by the NSHMP for the U.S. and its territories. This project includes a variety of command line applications and web service classes and relies on the nshmp-lib hazard library,nshmp-lib
nshmp-lib is a USGS developed Java library that supports probabilistic seismic hazard (PSHA) and related analyses. This project includes all the code required to load, process and query USGS National Seismic Hazard Models (NSHMs). nshmp-lib is used by command line applications and web services found in the nshmp-haz project. See that project for running PSHA calculations.nshm-fault-sections
A repository of all geologic fault section data included in USGS National Seismic Hazard Modelsnshmp-haz-v1
U.S. Geological Survey (USGS) National Seismic Hazard Mapping Project (NSHMP) code for performing probabilistic seismic hazard (PSHA) and related analyses. These codes are intended for use with seismic hazard models developed by the NSHMP for the U.S. and its territories.