Search Results - "STEPHENSON, William J"

Source‐Dependent Amplification of Earthquake Ground Motions in Deep Sedimentary Basins by Wirth, Erin A., Vidale, John E., Frankel, Arthur D., Pratt, Thomas L., Marafi, Nasser A., Thompson, Mika, Stephenson, William J.

“…Deep sedimentary basins amplify long‐period shaking from seismic waves, increasing the seismic hazard for cities sited on such basins. We perform 3‐D…”
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Microtremor array method using spatial autocorrelation analysis of Rayleigh-wave data by Hayashi, Koichi, Asten, Michael W., Stephenson, William J., Cornou, Cécile, Hobiger, Manuel, Pilz, Marco, Yamanaka, Hiroaki

“…Microtremor array measurements, and passive surface wave methods in general, have been increasingly used to non-invasively estimate shear-wave velocity…”
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Flexible multimethod approach for seismic site characterization by Stephenson, William J., Yong, Alan, Martin, Antony

“…We describe the flexible multimethod seismic site characterization technique for obtaining shear-wave velocity ( V S ) profiles and derivative information,…”
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3D crustal structure and long-period ground motions from a M9.0 megathrust earthquake in the Pacific Northwest region by Olsen, Kim B., Stephenson, William J., Geisselmeyer, Andreas

“…We have developed a community velocity model for the Pacific Northwest region from northern California to southern Canada and carried out the first 3D…”
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Empirical ground-motion basin response in the California Great Valley, Reno, Nevada, and Portland, Oregon by Ahdi, Sean K, Aagaard, Brad T, Moschetti, Morgan P, Parker, Grace A, Boyd, Oliver S, Stephenson, William J

“…We assess how well the Next-Generation Attenuation-West 2 (NGA-West2) ground-motion models (GMMs), which are used in the US Geological Survey’s (USGS) National…”
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Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland by Johnson, Samuel Y., Blakely, Richard J., Stephenson, William J., Dadisman, Shawn V., Fisher, Michael A.

“…Margin‐parallel shortening of the Cascadia forearc is a consequence of oblique subduction of the Juan de Fuca plate beneath North America. Strike‐slip, thrust,…”
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Shallow Faulting and Folding beneath South-Central Seattle, Washington State, from Land-Based High-Resolution Seismic-Reflection Imaging by Stephenson, William J., Odum, Jack K., Pratt, Thomas L.

“…The geologic framework of the Seattle fault zone (SFZ) has been extensively studied, but the structure and fault strand locations in the central portion of the…”
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The 2023 US National Seismic Hazard Model: Ground-motion characterization for the conterminous United States by Moschetti, Morgan P, Aagaard, Brad T, Ahdi, Sean K, Altekruse, Jason, Boyd, Oliver S, Frankel, Arthur D, Herrick, Julie, Petersen, Mark D, Powers, Peter M, Rezaeian, Sanaz, Shumway, Allison M, Smith, James A, Stephenson, William J, Thompson, Eric M, Withers, Kyle B

“…We update the ground-motion characterization for the 2023 National Seismic Hazard Model (NSHM) for the conterminous United States. The update includes the use…”
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Correction to: Microtremor array method using spatial autocorrelation analysis of Rayleigh-wave data by Hayashi, Koichi, Asten, Michael W., Stephenson, William J., Cornou, Cécile, Hobiger, Manuel, Pilz, Marco, Yamanaka, Hiroaki

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Toward resolving an earthquake ground motion mystery in west Seattle, Washington State: Shallow seismic focusing may cause anomalous chimney damage by Stephenson, William J., Frankel, Arthur D., Odum, Jack K., Williams, Robert A., Pratt, Thomas L.

“…A shallow bedrock fold imaged by a 1.3‐km long high‐resolution shear‐wave seismic reflection profile in west Seattle focuses seismic waves arriving from the…”
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Evidence for Late Quaternary Deformation Along Crowleys Ridge, New Madrid Seismic Zone by Thompson Jobe, Jessica A., Gold, Ryan D., Briggs, Richard W., Williams, Robert A., Stephenson, William J., Delano, Jaime E., Shah, Anjana, Minsley, Burke

“…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…”
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Seismic site characterization with shear wave (SH) reflection and refraction methods by Hunter, James A., Crow, Heather L., Stephenson, William J., Pugin, André J.-M., Williams, Robert A., Harris, James B., Odum, Jack K., Woolery, Edward W.

“…Reflection and critically refracted seismic methods use traveltime measurements of body waves propagating between a source and a series of receivers on the…”
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The Story of a Yakima Fold and How It Informs Late Neogene and Quaternary Backarc Deformation in the Cascadia Subduction Zone, Manastash Anticline, Washington, USA by Kelsey, Harvey M., Ladinsky, Tyler C., Staisch, Lydia, Sherrod, Brian L., Blakely, Richard J., Pratt, Thomas L., Stephenson, William J., Odum, Jack K., Wan, Elmira

“…The Yakima folds of central Washington, USA, are prominent anticlines that are the primary tectonic features of the backarc of the northern Cascadia subduction…”
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Seismic reflection evidence for a northeast-dipping Hayward fault near Fremont, California: Implications for seismic hazard by Williams, Robert A., Simpson, Robert W., Jachens, Robert C., Stephenson, William J., Odum, Jack K., Ponce, David A.

“…A 1.6‐km‐long seismic reflection profile across the creeping trace of the southern Hayward fault near Fremont, California, images the fault to a depth of 650…”
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An assessment of uncertainties in VS profiles obtained from microtremor observations in the phased 2018 COSMOS blind trials by Asten, Michael W., Yong, Alan, Foti, Sebastiano, Hayashi, Koichi, Martin, Antony J., Stephenson, William J., Cassidy, John F., Coleman, Jacie, Nigbor, Robert, Castellaro, Silvia, Chimoto, Kosuke, Cornou, Cécile, Cho, Ikuo, Hayashida, Takumi, Hobiger, Manuel, Kuo, Chun-Hsiang, Macau, Albert, Mercerat, E. Diego, Molnar, Sheri, Pananont, Passakorn, Pilz, Marco, Poovarodom, Nakhorn, Sáez, Esteban, Wathelet, Marc, Yamanaka, Hiroaki, Yokoi, Toshiaki, Zhao, Don

“…Site response is a critical consideration when assessing earthquake hazards. Site characterization is key to understanding site effects as influenced by…”
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Geophysical Constraints on the Crustal Architecture of the Transtensional Warm Springs Valley Fault Zone, Northern Walker Lane, Western Nevada, USA by Briggs, Rich W., Stephenson, William J., McBride, John H., Odum, Jackson K., Reitman, Nadine G., Gold, Ryan D.

“…The Walker Lane is a zone of distributed transtension where normal faults are overprinted by strike‐slip motion. We use two newly acquired, high‐resolution…”
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Seismic Reflection Imaging of the Low‐Angle Panamint Normal Fault System, Eastern California by Gold, Ryan D., Stephenson, William J., Briggs, Richard W., DuRoss, Christopher B., Kirby, Eric, Woolery, Edward, Delano, Jaime, Odum, Jack K.

“…Shallowly dipping (<30°) low‐angle normal faults (LANFs) have been documented globally; however, examples of active LANFs in continental settings are limited…”
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Concealed Quaternary strike-slip fault resolved with airborne lidar and seismic reflection: The Grizzly Valley fault system, northern Walker Lane, California by Gold, Ryan D., Stephenson, William J., Odum, Jack K., Briggs, Richard W., Crone, Anthony J., Angster, Stephen J.

“…The Grizzly Valley fault system (GVFS) strikes northwestward across Sierra Valley, a low‐relief basin situated within a network of active dextral slip faults…”
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Shallow P- and S-wave velocities and site resonances in the St. Louis region, Missouri-Illinois by Williams, Robert A, Odum, Jack K, Stephenson, William J, Herrmann, Robert B

“…As part of the seismic hazard-mapping efforts in the St. Louis metropolitan area we determined the compressional and shear-wave velocities (Vp and Vs) to about…”
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Study of a prehistoric landslide using seismic reflection methods integrated with geological data in the Wasatch Mountains, Utah, USA by Tingey, Brady E., McBride, John H., Thompson, Timothy J., Stephenson, William J., South, John V., Bushman, Michelle

“…An integration of geological and geophysical techniques characterizes the internal and basal structure of a landslide along the western margin of the Wasatch…”
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