William J Stephenson
Bill Stephensen is a scientist in the Earthquake Hazards Program.
Science and Products
Filter Total Items: 15
Shear-wave velocity in the Seattle basin to 2 km depth characterized with the krSPAC microtremor array method: insights for urban basin-scale imaging - Data Release Shear-wave velocity in the Seattle basin to 2 km depth characterized with the krSPAC microtremor array method: insights for urban basin-scale imaging - Data Release
The dataset for this investigation consists of microtremor array data collected at 11 sites in the Seattle basin, Washington State. Ten of the arrays consisted of seven Nanometrics Trillium Compact broadband sensors deployed in asymmetric nested triangles (sites ST01, BA02, SP04, LF05, UW06, SN07, RD08, EL09, CH10, and KG11) that recorded for up to six hours. The eleventh array, at site...
Data for Holocene fault reactivation in the eastern Cascades, WA Data for Holocene fault reactivation in the eastern Cascades, WA
Significant uncertainty remains in how and where crustal shortening occurs throughout the eastern Cascade Range in Washington State. Using lidar imagery, we identified a ~5 km long lineament in Swakane canyon near Wenatchee, roughly coincident with a strand of the Entiat fault. Topographic profiles across the lineament reveal a southwest-side-up break in slope with an average of ~3 m of...
Data for P- and S-wave Seismic Velocity Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion simulations- Update for Open-File Report 2007-1348 Data for P- and S-wave Seismic Velocity Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion simulations- Update for Open-File Report 2007-1348
The data for this release is an ASCII file containing grid points of Cascadia P- and S-wave velocity models. The model volume was developed to include the Cascadia subduction zone for purposes of ground motion simulation. The description of the model and background of its development is provided in the associated Open-File Report. The grid points are given in Universal Transverse...
Filter Total Items: 63
Shear-wave velocity site characterization in Oklahoma from joint inversion of multi-method surface seismic measurements: Implications for central U.S. Ground Motion Prediction Shear-wave velocity site characterization in Oklahoma from joint inversion of multi-method surface seismic measurements: Implications for central U.S. Ground Motion Prediction
We analyze multimethod shear (SH)‐wave velocity ( VS) site characterization data acquired at three permanent and 25 temporary seismograph stations in Oklahoma that recorded M 4+ earthquakes within a 50 km hypocentral distance of at least one of the 2016 M 5.1 Fairview, M 5.8 Pawnee, or M 5.0 Cushing earthquakes to better constrain earthquake ground‐motion modeling in the region. We...
Authors
William Stephenson, Jackson K. Odum, Stephen Hartzell, Alena Leeds, Robert Williams
Seismic reflection imaging of the low-angle Panamint normal fault system, eastern California Seismic reflection imaging of the low-angle Panamint normal fault system, eastern California
Shallowly dipping (
Authors
Ryan Gold, William Stephenson, Richard Briggs, Christopher DuRoss, Eric Kirby, Edward Woolery, Jaime Delano, Jackson K. Odum
Graphical Dispersion Plot Editor (DPE) for seismic-site characterization by using multiple surface-wave methods Graphical Dispersion Plot Editor (DPE) for seismic-site characterization by using multiple surface-wave methods
Introduction To understand the behavior of potentially damaging ground motions during earthquakes, seismic-site effects are routinely characterized by using the dispersion of surface waves. Many methods exist to measure dispersion; these methods have various advantages and disadvantages, but they all yield dispersion data that must be inverted for shear-wave velocity. This report...
Authors
Devin McPhillips, Alan Yong, Antony Martin, William Stephenson
Evidence for late Quaternary deformation along Crowley's Ridge, New Madrid seismic zone Evidence for late Quaternary deformation along Crowley's Ridge, New Madrid seismic zone
The New Madrid seismic zone has been the source of multiple major (M ~7.0–7.5) earthquakes in the past 2 ka, yet the surface expression of recent deformation remains ambiguous. Crowleys Ridge, a linear ridge trending north‐south for 300+ km through the Mississippi Embayment, has been interpreted as either a fault‐bounded uplift or a nontectonic erosional remnant. New and previously...
Authors
Jessica Thompson Jobe, Ryan Gold, Richard Briggs, Robert Williams, William Stephenson, Jaime Delano, Anjana Shah, Burke Minsley
Erratum to Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3D simulations and stochastic synthetics, Part 1: methodology and overall results Erratum to Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3D simulations and stochastic synthetics, Part 1: methodology and overall results
No abstract available.
Authors
Arthur Frankel, Erin Wirth, Nasser Marafi, John Vidale, William Stephenson
3-D Simulations of M9 earthquakes on the Cascadia Megathrust: Methodology and results 3-D Simulations of M9 earthquakes on the Cascadia Megathrust: Methodology and results
No abstract available.
Authors
Arthur Frankel, Erin Wirth Moriarty, J. Vidale, William Stephenson, Nasser Marafi
Science and Products
Filter Total Items: 15
Shear-wave velocity in the Seattle basin to 2 km depth characterized with the krSPAC microtremor array method: insights for urban basin-scale imaging - Data Release Shear-wave velocity in the Seattle basin to 2 km depth characterized with the krSPAC microtremor array method: insights for urban basin-scale imaging - Data Release
The dataset for this investigation consists of microtremor array data collected at 11 sites in the Seattle basin, Washington State. Ten of the arrays consisted of seven Nanometrics Trillium Compact broadband sensors deployed in asymmetric nested triangles (sites ST01, BA02, SP04, LF05, UW06, SN07, RD08, EL09, CH10, and KG11) that recorded for up to six hours. The eleventh array, at site...
Data for Holocene fault reactivation in the eastern Cascades, WA Data for Holocene fault reactivation in the eastern Cascades, WA
Significant uncertainty remains in how and where crustal shortening occurs throughout the eastern Cascade Range in Washington State. Using lidar imagery, we identified a ~5 km long lineament in Swakane canyon near Wenatchee, roughly coincident with a strand of the Entiat fault. Topographic profiles across the lineament reveal a southwest-side-up break in slope with an average of ~3 m of...
Data for P- and S-wave Seismic Velocity Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion simulations- Update for Open-File Report 2007-1348 Data for P- and S-wave Seismic Velocity Models Incorporating the Cascadia Subduction Zone for 3D Earthquake Ground Motion simulations- Update for Open-File Report 2007-1348
The data for this release is an ASCII file containing grid points of Cascadia P- and S-wave velocity models. The model volume was developed to include the Cascadia subduction zone for purposes of ground motion simulation. The description of the model and background of its development is provided in the associated Open-File Report. The grid points are given in Universal Transverse...
Filter Total Items: 63
Shear-wave velocity site characterization in Oklahoma from joint inversion of multi-method surface seismic measurements: Implications for central U.S. Ground Motion Prediction Shear-wave velocity site characterization in Oklahoma from joint inversion of multi-method surface seismic measurements: Implications for central U.S. Ground Motion Prediction
We analyze multimethod shear (SH)‐wave velocity ( VS) site characterization data acquired at three permanent and 25 temporary seismograph stations in Oklahoma that recorded M 4+ earthquakes within a 50 km hypocentral distance of at least one of the 2016 M 5.1 Fairview, M 5.8 Pawnee, or M 5.0 Cushing earthquakes to better constrain earthquake ground‐motion modeling in the region. We...
Authors
William Stephenson, Jackson K. Odum, Stephen Hartzell, Alena Leeds, Robert Williams
Seismic reflection imaging of the low-angle Panamint normal fault system, eastern California Seismic reflection imaging of the low-angle Panamint normal fault system, eastern California
Shallowly dipping (
Authors
Ryan Gold, William Stephenson, Richard Briggs, Christopher DuRoss, Eric Kirby, Edward Woolery, Jaime Delano, Jackson K. Odum
Graphical Dispersion Plot Editor (DPE) for seismic-site characterization by using multiple surface-wave methods Graphical Dispersion Plot Editor (DPE) for seismic-site characterization by using multiple surface-wave methods
Introduction To understand the behavior of potentially damaging ground motions during earthquakes, seismic-site effects are routinely characterized by using the dispersion of surface waves. Many methods exist to measure dispersion; these methods have various advantages and disadvantages, but they all yield dispersion data that must be inverted for shear-wave velocity. This report...
Authors
Devin McPhillips, Alan Yong, Antony Martin, William Stephenson
Evidence for late Quaternary deformation along Crowley's Ridge, New Madrid seismic zone Evidence for late Quaternary deformation along Crowley's Ridge, New Madrid seismic zone
The New Madrid seismic zone has been the source of multiple major (M ~7.0–7.5) earthquakes in the past 2 ka, yet the surface expression of recent deformation remains ambiguous. Crowleys Ridge, a linear ridge trending north‐south for 300+ km through the Mississippi Embayment, has been interpreted as either a fault‐bounded uplift or a nontectonic erosional remnant. New and previously...
Authors
Jessica Thompson Jobe, Ryan Gold, Richard Briggs, Robert Williams, William Stephenson, Jaime Delano, Anjana Shah, Burke Minsley
Erratum to Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3D simulations and stochastic synthetics, Part 1: methodology and overall results Erratum to Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3D simulations and stochastic synthetics, Part 1: methodology and overall results
No abstract available.
Authors
Arthur Frankel, Erin Wirth, Nasser Marafi, John Vidale, William Stephenson
3-D Simulations of M9 earthquakes on the Cascadia Megathrust: Methodology and results 3-D Simulations of M9 earthquakes on the Cascadia Megathrust: Methodology and results
No abstract available.
Authors
Arthur Frankel, Erin Wirth Moriarty, J. Vidale, William Stephenson, Nasser Marafi