Kevin R Milner
Kevin Milner is a Research Geophysicist with the Earthquake Hazards Program.
Kevin develops earthquake forecast models for the USGS Earthquake Hazards Program. His research interests include uncertainty quantification and reduction in seismic hazard analysis, and physics-based earthquake and ground motion simulation. With a background in both computer and geological sciences, he specializes in using high performance computing to tackle complex research problems.
Professional Experience
Research Geophysicist, USGS Geologic Hazards Science Center (2024–Present)
Computer Scientist, Southern California Earthquake Center (2008–2024)
Education and Certifications
PhD (Geological Sciences); University of Southern California, 2020
MS (Geological Sciences); University of Southern California, 2015
BS (Computer Sciences); University of Southern California, 2007
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...
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: 26
A scientific vision and roadmap for earthquake rupture forecast developments, a USGS perspective A scientific vision and roadmap for earthquake rupture forecast developments, a USGS perspective
We articulate a scientific vision and roadmap for the development of improved Earthquake Rupture Forecast models, which are one of the two main modeling components used in modern seismic hazard and risk analysis. One primary future objective is to provide fully time-dependent models that include both elastic rebound and spatiotemporal clustering nationwide, which is particularly...
Authors
Edward Field, Alexandra Hatem, Bruce Shaw, Morgan Page, P. Mai, Kevin Ross Milner, Andrea Llenos, Andrew Michael, Frederick Pollitz, Jessica Jobe, Thomas Parsons, Olaf Zielke, David Shelly, Alice-Agnes Gabriel, Devin McPhillips, Richard Briggs, Elizabeth Cochran, Nico Luco, Mark Petersen, Peter Powers, Justin Rubinstein, Allison Shumway, Nicholas van der Elst, Yuehua Zeng, Christopher DuRoss, Jason Altekruse
Risk implications of Poisson assumptions and declustering inferred from a fully time-dependent earthquake forecast Risk implications of Poisson assumptions and declustering inferred from a fully time-dependent earthquake forecast
We use the Third Uniform California Earthquake Rupture Forecast Epidemic Type Aftershock Sequence model, which is fully time-dependent in terms of including spatiotemporal clustering, to evaluate the effects of the Poisson assumption and declustering algorithms on statewide loss exceedance curves. The model is simulation based, meaning it produces synthetic catalogs that exhibit...
Authors
Edward Field, Kevin Ross Milner, Keith Porter
Deterministic physics-based earthquake sequence simulators match empirical ground-motion models and enable extrapolation to data poor regimes: Application to multifault multimechanism ruptures Deterministic physics-based earthquake sequence simulators match empirical ground-motion models and enable extrapolation to data poor regimes: Application to multifault multimechanism ruptures
We use the deterministic earthquake simulator RSQSim to generate complex sequences of ruptures on fault systems used for hazard assessment. We show that the source motions combined with a wave propagation code create surface ground motions that fall within the range of epistemic uncertainties for the Next Generation Attenuation‐West2 set of empirical models. We show the model is well...
Authors
Bruce Shaw, Kevin Ross Milner, Christine Goulet
The USGS 2023 Conterminous U.S. time‐independent earthquake rupture forecast The USGS 2023 Conterminous U.S. time‐independent earthquake rupture forecast
We present the 2023 U.S. Geological Survey time‐independent earthquake rupture forecast for the conterminous United States, which gives authoritative estimates of the magnitude, location, and time‐averaged frequency of potentially damaging earthquakes throughout the region. In addition to updating virtually all model components, a major focus has been to provide a better representation...
Authors
Edward Field, Kevin Milner, Alexandra Hatem, Peter Powers, Frederick Pollitz, Andrea Llenos, Yuehua Zeng, Kaj Johnson, Bruce Shaw, Devin McPhillips, Jessica Jobe, Allison Shumway, Andrew Michael, Zheng-Kang Shen, Eileen L. Evans, Elizabeth Hearn, Charles Mueller, Arthur Frankel, Mark Petersen, Christopher DuRoss, Richard Briggs, Morgan Page, Justin Rubinstein, Julie Herrick
A comprehensive fault system inversion approach: Methods and application to NSHM23 A comprehensive fault system inversion approach: Methods and application to NSHM23
We present updated inversion‐based fault‐system solutions for the 2023 update to the National Seismic Hazard Model (NSHM23), standardizing earthquake rate model calculations on crustal faults across the western United States. We build upon the inversion methodology used in the Third Uniform California Earthquake Rupture Forecast (UCERF3) to solve for time‐independent rates of earthquakes...
Authors
Kevin Milner, Edward Field
Enumerating plausible multifault ruptures in complex fault systems with physical constraints Enumerating plausible multifault ruptures in complex fault systems with physical constraints
We propose a new model for determining the set of plausible multifault ruptures in an interconnected fault system. We improve upon the rules used in the Third Uniform California Earthquake Rupture Forecast (UCERF3) to increase connectivity and the physical consistency of ruptures. We replace UCERF3’s simple azimuth change rules with new Coulomb favorability metrics and increase the...
Authors
Kevin Milner, Bruce Shaw, Edward Field
The seismic hazard implications of declustering and poisson assumptions inferred from a fully time‐dependent model The seismic hazard implications of declustering and poisson assumptions inferred from a fully time‐dependent model
We use the Third Uniform California Earthquake Rupture Forecast (UCERF3) epidemic‐type aftershock sequence (ETAS) model (UCERF3‐ETAS) to evaluate the effects of declustering and Poisson assumptions on seismic hazard estimates. Although declustering is necessary to infer the long‐term spatial distribution of earthquake rates, the question is whether it is also necessary to honor the...
Authors
Edward Field, Kevin Milner, Nico Luco
Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS) Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS)
We describe recent improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS), which continues to represent our most advanced and complete earthquake forecast in terms of relaxing segmentation assumptions and representing multifault ruptures, elastic‐rebound effects, and spatiotemporal clustering (the latter to represent aftershocks and otherwise...
Authors
Edward Field, Kevin Milner, Morgan Page, William Savran, Nicholas van der Elst
Toward physics-based nonergodic PSHA: A prototype fully-deterministic seismic hazard model for southern California Toward physics-based nonergodic PSHA: A prototype fully-deterministic seismic hazard model for southern California
We present a nonergodic framework for probabilistic seismic‐hazard analysis (PSHA) that is constructed entirely of deterministic, physical models. The use of deterministic ground‐motion simulations in PSHA calculations is not new (e.g., CyberShake), but prior studies relied on kinematic rupture generators to extend empirical earthquake rupture forecasts. Fully dynamic models, which...
Authors
Kevin Milner, Bruce Shaw, Christine Goulet, Keith Richards-Dinger, Scott Callaghan, Thomas Jordan, James Dieterich, Edward Field
Generalizing the inversion‐based PSHA source model for an interconnected fault system Generalizing the inversion‐based PSHA source model for an interconnected fault system
This article represents a step toward generalizing and simplifying the procedure for constructing an inversion‐based seismic hazard source model for an interconnected fault system, including the specification of adjustable segmentation constraints. A very simple example is used to maximize understandability and to counter the notion that an inversion approach is only applicable when an...
Authors
Edward Field, Kevin Milner, Morgan Page
Pseudo-prospective evaluation of UCERF3-ETAS forecasts during the 2019 Ridgecrest sequence Pseudo-prospective evaluation of UCERF3-ETAS forecasts during the 2019 Ridgecrest sequence
The 2019 Ridgecrest sequence provides the first opportunity to evaluate Uniform California Earthquake Rupture Forecast v.3 with epidemic‐type aftershock sequences (UCERF3‐ETAS) in a pseudoprospective sense. For comparison, we include a version of the model without explicit faults more closely mimicking traditional ETAS models (UCERF3‐NoFaults). We evaluate the forecasts with new metrics...
Authors
William Savran, Maximillian Werner, W. Marzocchi, David Rhoades, David D. Jackson, Kevin Milner, Edward H. Field, Andrew Michael
Assessing the value of removing earthquake-hazard-related epistemic uncertainties, exemplified using average annual loss in California Assessing the value of removing earthquake-hazard-related epistemic uncertainties, exemplified using average annual loss in California
To aid in setting scientific research priorities, we assess the potential value of removing each of the epistemic uncertainties currently represented in the US Geological Survey California seismic-hazard model, using average annual loss (AAL) as the risk metric of interest. Given all the uncertainties, represented with logic-tree branches, we find a mean AAL of $3.94 billion. The modal...
Authors
Edward H. Field, Kevin Milner, Keith Porter
Non-USGS Publications**
**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.
Aftershock Forecaster Aftershock Forecaster
Aftershock Forecaster is a GUI program that runs on the desktop and is used to compute ETAS-based aftershock forecasts.
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...
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: 26
A scientific vision and roadmap for earthquake rupture forecast developments, a USGS perspective A scientific vision and roadmap for earthquake rupture forecast developments, a USGS perspective
We articulate a scientific vision and roadmap for the development of improved Earthquake Rupture Forecast models, which are one of the two main modeling components used in modern seismic hazard and risk analysis. One primary future objective is to provide fully time-dependent models that include both elastic rebound and spatiotemporal clustering nationwide, which is particularly...
Authors
Edward Field, Alexandra Hatem, Bruce Shaw, Morgan Page, P. Mai, Kevin Ross Milner, Andrea Llenos, Andrew Michael, Frederick Pollitz, Jessica Jobe, Thomas Parsons, Olaf Zielke, David Shelly, Alice-Agnes Gabriel, Devin McPhillips, Richard Briggs, Elizabeth Cochran, Nico Luco, Mark Petersen, Peter Powers, Justin Rubinstein, Allison Shumway, Nicholas van der Elst, Yuehua Zeng, Christopher DuRoss, Jason Altekruse
Risk implications of Poisson assumptions and declustering inferred from a fully time-dependent earthquake forecast Risk implications of Poisson assumptions and declustering inferred from a fully time-dependent earthquake forecast
We use the Third Uniform California Earthquake Rupture Forecast Epidemic Type Aftershock Sequence model, which is fully time-dependent in terms of including spatiotemporal clustering, to evaluate the effects of the Poisson assumption and declustering algorithms on statewide loss exceedance curves. The model is simulation based, meaning it produces synthetic catalogs that exhibit...
Authors
Edward Field, Kevin Ross Milner, Keith Porter
Deterministic physics-based earthquake sequence simulators match empirical ground-motion models and enable extrapolation to data poor regimes: Application to multifault multimechanism ruptures Deterministic physics-based earthquake sequence simulators match empirical ground-motion models and enable extrapolation to data poor regimes: Application to multifault multimechanism ruptures
We use the deterministic earthquake simulator RSQSim to generate complex sequences of ruptures on fault systems used for hazard assessment. We show that the source motions combined with a wave propagation code create surface ground motions that fall within the range of epistemic uncertainties for the Next Generation Attenuation‐West2 set of empirical models. We show the model is well...
Authors
Bruce Shaw, Kevin Ross Milner, Christine Goulet
The USGS 2023 Conterminous U.S. time‐independent earthquake rupture forecast The USGS 2023 Conterminous U.S. time‐independent earthquake rupture forecast
We present the 2023 U.S. Geological Survey time‐independent earthquake rupture forecast for the conterminous United States, which gives authoritative estimates of the magnitude, location, and time‐averaged frequency of potentially damaging earthquakes throughout the region. In addition to updating virtually all model components, a major focus has been to provide a better representation...
Authors
Edward Field, Kevin Milner, Alexandra Hatem, Peter Powers, Frederick Pollitz, Andrea Llenos, Yuehua Zeng, Kaj Johnson, Bruce Shaw, Devin McPhillips, Jessica Jobe, Allison Shumway, Andrew Michael, Zheng-Kang Shen, Eileen L. Evans, Elizabeth Hearn, Charles Mueller, Arthur Frankel, Mark Petersen, Christopher DuRoss, Richard Briggs, Morgan Page, Justin Rubinstein, Julie Herrick
A comprehensive fault system inversion approach: Methods and application to NSHM23 A comprehensive fault system inversion approach: Methods and application to NSHM23
We present updated inversion‐based fault‐system solutions for the 2023 update to the National Seismic Hazard Model (NSHM23), standardizing earthquake rate model calculations on crustal faults across the western United States. We build upon the inversion methodology used in the Third Uniform California Earthquake Rupture Forecast (UCERF3) to solve for time‐independent rates of earthquakes...
Authors
Kevin Milner, Edward Field
Enumerating plausible multifault ruptures in complex fault systems with physical constraints Enumerating plausible multifault ruptures in complex fault systems with physical constraints
We propose a new model for determining the set of plausible multifault ruptures in an interconnected fault system. We improve upon the rules used in the Third Uniform California Earthquake Rupture Forecast (UCERF3) to increase connectivity and the physical consistency of ruptures. We replace UCERF3’s simple azimuth change rules with new Coulomb favorability metrics and increase the...
Authors
Kevin Milner, Bruce Shaw, Edward Field
The seismic hazard implications of declustering and poisson assumptions inferred from a fully time‐dependent model The seismic hazard implications of declustering and poisson assumptions inferred from a fully time‐dependent model
We use the Third Uniform California Earthquake Rupture Forecast (UCERF3) epidemic‐type aftershock sequence (ETAS) model (UCERF3‐ETAS) to evaluate the effects of declustering and Poisson assumptions on seismic hazard estimates. Although declustering is necessary to infer the long‐term spatial distribution of earthquake rates, the question is whether it is also necessary to honor the...
Authors
Edward Field, Kevin Milner, Nico Luco
Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS) Improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS)
We describe recent improvements to the Third Uniform California Earthquake Rupture Forecast ETAS Model (UCERF3‐ETAS), which continues to represent our most advanced and complete earthquake forecast in terms of relaxing segmentation assumptions and representing multifault ruptures, elastic‐rebound effects, and spatiotemporal clustering (the latter to represent aftershocks and otherwise...
Authors
Edward Field, Kevin Milner, Morgan Page, William Savran, Nicholas van der Elst
Toward physics-based nonergodic PSHA: A prototype fully-deterministic seismic hazard model for southern California Toward physics-based nonergodic PSHA: A prototype fully-deterministic seismic hazard model for southern California
We present a nonergodic framework for probabilistic seismic‐hazard analysis (PSHA) that is constructed entirely of deterministic, physical models. The use of deterministic ground‐motion simulations in PSHA calculations is not new (e.g., CyberShake), but prior studies relied on kinematic rupture generators to extend empirical earthquake rupture forecasts. Fully dynamic models, which...
Authors
Kevin Milner, Bruce Shaw, Christine Goulet, Keith Richards-Dinger, Scott Callaghan, Thomas Jordan, James Dieterich, Edward Field
Generalizing the inversion‐based PSHA source model for an interconnected fault system Generalizing the inversion‐based PSHA source model for an interconnected fault system
This article represents a step toward generalizing and simplifying the procedure for constructing an inversion‐based seismic hazard source model for an interconnected fault system, including the specification of adjustable segmentation constraints. A very simple example is used to maximize understandability and to counter the notion that an inversion approach is only applicable when an...
Authors
Edward Field, Kevin Milner, Morgan Page
Pseudo-prospective evaluation of UCERF3-ETAS forecasts during the 2019 Ridgecrest sequence Pseudo-prospective evaluation of UCERF3-ETAS forecasts during the 2019 Ridgecrest sequence
The 2019 Ridgecrest sequence provides the first opportunity to evaluate Uniform California Earthquake Rupture Forecast v.3 with epidemic‐type aftershock sequences (UCERF3‐ETAS) in a pseudoprospective sense. For comparison, we include a version of the model without explicit faults more closely mimicking traditional ETAS models (UCERF3‐NoFaults). We evaluate the forecasts with new metrics...
Authors
William Savran, Maximillian Werner, W. Marzocchi, David Rhoades, David D. Jackson, Kevin Milner, Edward H. Field, Andrew Michael
Assessing the value of removing earthquake-hazard-related epistemic uncertainties, exemplified using average annual loss in California Assessing the value of removing earthquake-hazard-related epistemic uncertainties, exemplified using average annual loss in California
To aid in setting scientific research priorities, we assess the potential value of removing each of the epistemic uncertainties currently represented in the US Geological Survey California seismic-hazard model, using average annual loss (AAL) as the risk metric of interest. Given all the uncertainties, represented with logic-tree branches, we find a mean AAL of $3.94 billion. The modal...
Authors
Edward H. Field, Kevin Milner, Keith Porter
Non-USGS Publications**
**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.
Aftershock Forecaster Aftershock Forecaster
Aftershock Forecaster is a GUI program that runs on the desktop and is used to compute ETAS-based aftershock forecasts.