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Morgan T Page

Morgan Page is a geophysicist in the Earthquake Science Center.

Science and Products

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stark landscape with a rip going across the surface from front to back

Southern California Earthquake Hazards

Southern California has the highest level of earthquake risk in the United States, with half of the expected financial losses from earthquakes in the Nation expected to occur in southern California. Sitting astride the Pacific - North American plate boundary at the Big Bend of the San Andreas Fault, Southern California has over 300 faults capable of producing magnitude 6 and larger earthquakes...
By
Natural Hazards Mission Area, Earthquake Hazards Program
link

Southern California Earthquake Hazards

Southern California has the highest level of earthquake risk in the United States, with half of the expected financial losses from earthquakes in the Nation expected to occur in southern California. Sitting astride the Pacific - North American plate boundary at the Big Bend of the San Andreas Fault, Southern California has over 300 faults capable of producing magnitude 6 and larger earthquakes...
Learn More
link
Map showing regional faults and Coso field near Ridgecrest

Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?

Release Date: SEPTEMBER 30, 2019 Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center
link

Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?

Release Date: SEPTEMBER 30, 2019 Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
Learn More
link
Map showing aftershocks of 7.8 earthquake in Oaxaca, Mexico

The Past Holds the Key to the Future of Aftershock Forecasting

Release Date: MAY 7, 2018 The outcomes of past aftershock sequences can be used to describe the range of possibilities for a current sequence.
By
Natural Hazards Mission Area, Earthquake Hazards Program
link

The Past Holds the Key to the Future of Aftershock Forecasting

Release Date: MAY 7, 2018 The outcomes of past aftershock sequences can be used to describe the range of possibilities for a current sequence.
Learn More
link
USGS science for a changing world logo

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
By
John Wesley Powell Center for Analysis and Synthesis
link

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
Learn More
link
USGS science for a changing world logo

Joint USGS - GEM Group on Global Probabilistic Modeling of Earthquake Recurrence Rates and Maximum Magnitudes

Despite the best monitoring networks, the highest rate of earthquakes and the longest continuous recorded history in the world, this year’s M=9.0 Tohoku, Japan, earthquake was completely unforeseen. The Japanese had expected no larger than a M=8 quake in the Japan trench, 1/30 th the size of the Tohoku temblor. This year also saw the devastating M=6.3 Christchurch, New Zealand earthquake and the M
By
John Wesley Powell Center for Analysis and Synthesis
link

Joint USGS - GEM Group on Global Probabilistic Modeling of Earthquake Recurrence Rates and Maximum Magnitudes

Despite the best monitoring networks, the highest rate of earthquakes and the longest continuous recorded history in the world, this year’s M=9.0 Tohoku, Japan, earthquake was completely unforeseen. The Japanese had expected no larger than a M=8 quake in the Japan trench, 1/30 th the size of the Tohoku temblor. This year also saw the devastating M=6.3 Christchurch, New Zealand earthquake and the M
Learn More

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 input to the
By
Earthquake Hazards Program
Filter Total Items: 33

Aftershock forecasting

Aftershocks can compound the impacts of a major earthquake, disrupting recovery efforts and potentially further damaging weakened buildings and infrastructure. Forecasts of the probability of aftershocks can therefore aid decision-making during earthquake response and recovery. Several countries issue authoritative aftershock forecasts. Most aftershock forecasts are based on simple statistical
Authors
Jeanne L. Hardebeck, Andrea L. Llenos, Andrew J. Michael, Morgan T. Page, Max Schneider, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

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 (both increase
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Edward H. Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nicolas Luco, Kenneth S. Rukstales, Julie A Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon Clayton, Christopher 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 (Ben) Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Fred Pollitz, Justin Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica Ann Thompson Jobe, Erin Wirth, Robert C. Witter
By
Natural Hazards Mission Area, Earthquake Hazards Program, Geologic Hazards Science Center, Supplemental Appropriations for Disaster Recovery Activities

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 of epistemi

Authors
Edward H. Field, Kevin R. Milner, Alexandra Elise Hatem, Peter M. Powers, Fred Pollitz, Andrea L. Llenos, Yuehua Zeng, Kaj M. Johnson, Bruce E. Shaw, Devin McPhillips, Jessica Ann Thompson Jobe, Allison Shumway, Andrew J. Michael, Zheng-Kang Shen, Eileen L. Evans, Elizabeth H. Hearn, Charles Mueller, Arthur Frankel, Mark D. Petersen, Christopher DuRoss, Richard W. Briggs, Morgan T. Page, Justin Rubinstein, Julie A Herrick
By
Natural Hazards Mission Area, Earthquake Hazards Program, Geologic Hazards Science Center, Earthquake Science Center

a-positive: A robust estimator of the earthquake rate in incomplete or saturated catalogs

Detection thresholds in earthquake catalogs frequently change in time due to station coverage improvements and network saturation effects during active periods such as mainshock-aftershock cascades. This presents a challenge to seismicity-rate estimation; there is a tradeoff between using as low a minimum magnitude as possible to maximize data while not undercounting the rate due to catalog incomp
Authors
Nicholas van der Elst, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Fault roughness at seismogenic depths and links to earthquake behavior

Fault geometry affects the initiation, propagation, and cessation of earthquake rupture, as well as, potentially, the statistical behavior of earthquake sequences. We analyze 18,250 (−0.27 < M < 4.4) earthquakes of the 2016–2019 Cahuilla, California, swarm and, for the first time, use these high‐resolution earthquake locations to map, in detail, the roughness across an active fault surface at dept
Authors
Elizabeth S. Cochran, Morgan T. Page, Nicholas van der Elst, Zachary E. Ross, Daniel T. Trugman
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Aftershocks preferentially occur in previously active areas

The clearest statistical signal in aftershock locations is that most aftershocks occur close to their mainshocks. More precisely, aftershocks are triggered at distances following a power‐law decay in distance (Felzer and Brodsky, 2006). This distance decay kernel is used in epidemic‐type aftershock sequence (ETAS) modeling and is typically assumed to be isotropic, even though individual sequences
Authors
Morgan T. Page, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

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 triggered ev
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page, William H. Savran, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

Apparent earthquake rupture predictability

To what extent can the future evolution of an ongoing earthquake rupture be predicted? This question of fundamental scientific and practical importance has recently been addressed by studies of teleseismic source time functions (STFs) but reaching contrasting conclusions. One study concludes that the initial portion of STFs is the same regardless of magnitude. Another study concludes that the rate
Authors
M.-A. Meier, P. Ampuero, Elizabeth S. Cochran, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

The normal faulting 2020 Mw5.8 Lone Pine, Eastern California earthquake sequence

The 2020 Mw 5.8 Lone Pine earthquake, the largest earthquake on the Owens Valley fault zone, eastern California, since the nineteenth century, ruptured an extensional stepover in that fault. Owens Valley separates two normal‐faulting regimes, the western margin of the Great basin and the eastern margin of the Sierra Nevada, forming a complex seismotectonic zone, and a possible nascent plate bounda
Authors
Egill Hauksson, Brian J. Olsen, Alex R. R. Grant, Jennifer R Andrews, Angela I. Chung, Susan E. Hough, Hiroo Kanamori, Sara McBride, Andrew J. Michael, Morgan T. Page, Zachary E. Ross, Deborah Smith, Sotiris Valkaniotis
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Revisiting California’s past great earthquakes and long-term earthquake rate

In this study, we revisit the three largest historical earthquakes in California—the 1857 Fort Tejon, 1872 Owens Valley, and 1906 San Francisco earthquakes—to review their published moment magnitudes, and compare their estimated shaking distributions with predictions using modern ground‐motion models (GMMs) and ground‐motion intensity conversion equations. Currently accepted moment magnitude estim
Authors
Susan E. Hough, Morgan T. Page, Leah Salditch, Molly M. Gallahue, Madeleine C. Lucas, James S. Neely, Seth Stein
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

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 abundance o
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

More fault connectivity Is needed in seismic hazard analysis

Did the third Uniform California Earthquake Rupture Forecast (UCERF3) go overboard with multifault ruptures? Schwartz (2018) argues that there are too many long ruptures in the model. Here, I address his concern and show that the UCERF3 rupture‐length distribution matches empirical data. I also present evidence that, if anything, the UCERF3 model could be improved by adding more connectivity to th
Authors
Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center
Threat of Earthquakes Occurring in Central United States Still Alive

Threat of Earthquakes Occurring in Central United States Still Alive

Earthquake activity in the New Madrid Seismic Zone in the central United States does not seem to be slowing down.  In a new study published in the...

Read Article

Science and Products

link
stark landscape with a rip going across the surface from front to back

Southern California Earthquake Hazards

Southern California has the highest level of earthquake risk in the United States, with half of the expected financial losses from earthquakes in the Nation expected to occur in southern California. Sitting astride the Pacific - North American plate boundary at the Big Bend of the San Andreas Fault, Southern California has over 300 faults capable of producing magnitude 6 and larger earthquakes...
By
Natural Hazards Mission Area, Earthquake Hazards Program
link

Southern California Earthquake Hazards

Southern California has the highest level of earthquake risk in the United States, with half of the expected financial losses from earthquakes in the Nation expected to occur in southern California. Sitting astride the Pacific - North American plate boundary at the Big Bend of the San Andreas Fault, Southern California has over 300 faults capable of producing magnitude 6 and larger earthquakes...
Learn More
link
Map showing regional faults and Coso field near Ridgecrest

Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?

Release Date: SEPTEMBER 30, 2019 Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center
link

Could the M7.1 Ridgecrest, CA Earthquake Sequence Trigger a Large Earthquake Nearby?

Release Date: SEPTEMBER 30, 2019 Two of the first questions that come to mind for anyone who just felt an earthquake are, “Will there be another one?” and “Will it be larger?”.
Learn More
link
Map showing aftershocks of 7.8 earthquake in Oaxaca, Mexico

The Past Holds the Key to the Future of Aftershock Forecasting

Release Date: MAY 7, 2018 The outcomes of past aftershock sequences can be used to describe the range of possibilities for a current sequence.
By
Natural Hazards Mission Area, Earthquake Hazards Program
link

The Past Holds the Key to the Future of Aftershock Forecasting

Release Date: MAY 7, 2018 The outcomes of past aftershock sequences can be used to describe the range of possibilities for a current sequence.
Learn More
link
USGS science for a changing world logo

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
By
John Wesley Powell Center for Analysis and Synthesis
link

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
Learn More
link
USGS science for a changing world logo

Joint USGS - GEM Group on Global Probabilistic Modeling of Earthquake Recurrence Rates and Maximum Magnitudes

Despite the best monitoring networks, the highest rate of earthquakes and the longest continuous recorded history in the world, this year’s M=9.0 Tohoku, Japan, earthquake was completely unforeseen. The Japanese had expected no larger than a M=8 quake in the Japan trench, 1/30 th the size of the Tohoku temblor. This year also saw the devastating M=6.3 Christchurch, New Zealand earthquake and the M
By
John Wesley Powell Center for Analysis and Synthesis
link

Joint USGS - GEM Group on Global Probabilistic Modeling of Earthquake Recurrence Rates and Maximum Magnitudes

Despite the best monitoring networks, the highest rate of earthquakes and the longest continuous recorded history in the world, this year’s M=9.0 Tohoku, Japan, earthquake was completely unforeseen. The Japanese had expected no larger than a M=8 quake in the Japan trench, 1/30 th the size of the Tohoku temblor. This year also saw the devastating M=6.3 Christchurch, New Zealand earthquake and the M
Learn More

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 input to the
By
Earthquake Hazards Program
Filter Total Items: 33

Aftershock forecasting

Aftershocks can compound the impacts of a major earthquake, disrupting recovery efforts and potentially further damaging weakened buildings and infrastructure. Forecasts of the probability of aftershocks can therefore aid decision-making during earthquake response and recovery. Several countries issue authoritative aftershock forecasts. Most aftershock forecasts are based on simple statistical
Authors
Jeanne L. Hardebeck, Andrea L. Llenos, Andrew J. Michael, Morgan T. Page, Max Schneider, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

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 (both increase
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Edward H. Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nicolas Luco, Kenneth S. Rukstales, Julie A Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon Clayton, Christopher 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 (Ben) Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Fred Pollitz, Justin Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica Ann Thompson Jobe, Erin Wirth, Robert C. Witter
By
Natural Hazards Mission Area, Earthquake Hazards Program, Geologic Hazards Science Center, Supplemental Appropriations for Disaster Recovery Activities

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 of epistemi

Authors
Edward H. Field, Kevin R. Milner, Alexandra Elise Hatem, Peter M. Powers, Fred Pollitz, Andrea L. Llenos, Yuehua Zeng, Kaj M. Johnson, Bruce E. Shaw, Devin McPhillips, Jessica Ann Thompson Jobe, Allison Shumway, Andrew J. Michael, Zheng-Kang Shen, Eileen L. Evans, Elizabeth H. Hearn, Charles Mueller, Arthur Frankel, Mark D. Petersen, Christopher DuRoss, Richard W. Briggs, Morgan T. Page, Justin Rubinstein, Julie A Herrick
By
Natural Hazards Mission Area, Earthquake Hazards Program, Geologic Hazards Science Center, Earthquake Science Center

a-positive: A robust estimator of the earthquake rate in incomplete or saturated catalogs

Detection thresholds in earthquake catalogs frequently change in time due to station coverage improvements and network saturation effects during active periods such as mainshock-aftershock cascades. This presents a challenge to seismicity-rate estimation; there is a tradeoff between using as low a minimum magnitude as possible to maximize data while not undercounting the rate due to catalog incomp
Authors
Nicholas van der Elst, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Fault roughness at seismogenic depths and links to earthquake behavior

Fault geometry affects the initiation, propagation, and cessation of earthquake rupture, as well as, potentially, the statistical behavior of earthquake sequences. We analyze 18,250 (−0.27 < M < 4.4) earthquakes of the 2016–2019 Cahuilla, California, swarm and, for the first time, use these high‐resolution earthquake locations to map, in detail, the roughness across an active fault surface at dept
Authors
Elizabeth S. Cochran, Morgan T. Page, Nicholas van der Elst, Zachary E. Ross, Daniel T. Trugman
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Aftershocks preferentially occur in previously active areas

The clearest statistical signal in aftershock locations is that most aftershocks occur close to their mainshocks. More precisely, aftershocks are triggered at distances following a power‐law decay in distance (Felzer and Brodsky, 2006). This distance decay kernel is used in epidemic‐type aftershock sequence (ETAS) modeling and is typically assumed to be isotropic, even though individual sequences
Authors
Morgan T. Page, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

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 triggered ev
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page, William H. Savran, Nicholas van der Elst
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

Apparent earthquake rupture predictability

To what extent can the future evolution of an ongoing earthquake rupture be predicted? This question of fundamental scientific and practical importance has recently been addressed by studies of teleseismic source time functions (STFs) but reaching contrasting conclusions. One study concludes that the initial portion of STFs is the same regardless of magnitude. Another study concludes that the rate
Authors
M.-A. Meier, P. Ampuero, Elizabeth S. Cochran, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

The normal faulting 2020 Mw5.8 Lone Pine, Eastern California earthquake sequence

The 2020 Mw 5.8 Lone Pine earthquake, the largest earthquake on the Owens Valley fault zone, eastern California, since the nineteenth century, ruptured an extensional stepover in that fault. Owens Valley separates two normal‐faulting regimes, the western margin of the Great basin and the eastern margin of the Sierra Nevada, forming a complex seismotectonic zone, and a possible nascent plate bounda
Authors
Egill Hauksson, Brian J. Olsen, Alex R. R. Grant, Jennifer R Andrews, Angela I. Chung, Susan E. Hough, Hiroo Kanamori, Sara McBride, Andrew J. Michael, Morgan T. Page, Zachary E. Ross, Deborah Smith, Sotiris Valkaniotis
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

Revisiting California’s past great earthquakes and long-term earthquake rate

In this study, we revisit the three largest historical earthquakes in California—the 1857 Fort Tejon, 1872 Owens Valley, and 1906 San Francisco earthquakes—to review their published moment magnitudes, and compare their estimated shaking distributions with predictions using modern ground‐motion models (GMMs) and ground‐motion intensity conversion equations. Currently accepted moment magnitude estim
Authors
Susan E. Hough, Morgan T. Page, Leah Salditch, Molly M. Gallahue, Madeleine C. Lucas, James S. Neely, Seth Stein
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center

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 abundance o
Authors
Edward H. Field, Kevin R. Milner, Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geologic Hazards Science Center

More fault connectivity Is needed in seismic hazard analysis

Did the third Uniform California Earthquake Rupture Forecast (UCERF3) go overboard with multifault ruptures? Schwartz (2018) argues that there are too many long ruptures in the model. Here, I address his concern and show that the UCERF3 rupture‐length distribution matches empirical data. I also present evidence that, if anything, the UCERF3 model could be improved by adding more connectivity to th
Authors
Morgan T. Page
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center
Threat of Earthquakes Occurring in Central United States Still Alive

Threat of Earthquakes Occurring in Central United States Still Alive

Earthquake activity in the New Madrid Seismic Zone in the central United States does not seem to be slowing down.  In a new study published in the...

Read Article
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