Alex is a Research Engineer specializing in regional-scale landslide and liquefaction hazards and risk.
Alex got his Ph.D. in 2017 from the University of Washington where he studied coseismic landslide hazard and risk in Lebanon, New Zealand, Japan, and the Pacific Northwest of N. America. Alex received his BSCE from Tufts University in 2013 and a MSE in 2014 from the University of Washington in Geotechnical Engineering. Alex joined the USGS in 2018 to research earthquake-induced ground failures, and is actively working on projects in the Pacific Northwest and California.
Science and Products
Crustal Characterization
Limits to coseismic landslides triggered by Cascadia Subduction Zone earthquakes
Regional-scale liquefaction analyses
Changes in liquefaction severity in the San Francisco Bay Area with sea-level rise
The normal faulting 2020 Mw5.8 Lone Pine, Eastern California earthquake sequence
Site response, basin amplification, and earthquake stress drops in the Portland, Oregon area
Ensemble ShakeMaps for magnitude 9 earthquakes on the Cascadia Subduction Zone
A generic soil velocity model that accounts for near-surface conditions and deeper geologic structure
Rainfall triggers more deep-seated landslides than Cascadia earthquakes in the Oregon Coast Range, USA
Ground failure triggered by shaking during the November 30, 2018, magnitude 7.1 Anchorage, Alaska, earthquake
Probabilistic regional-scale liquefaction triggering modeling using 3D Gaussian processes
USGS near-real-time products-and their use-for the 2018 Anchorage earthquake
Ground failure from the Anchorage, Alaska, earthquake of 30 November 2018
Liquefaction and Sea-Level Rise
USGS scientists published a storymap explaining the impacts of sea-level rise on liquefaction severity around the San Francisco Bay Area, California for the magnitude 7.0 ‘HayWired’ earthquake scenario along the Hayward Fault.
Science and Products
- Science
Crustal Characterization
The geophysical structure of the Earth’s crust, from the surface to the Moho, plays a major role in seismic hazard by influencing earthquake source properties and wave propagation from the earthquake to the Earth’s surface. We make field measurements and create models to better characterize the crust and resulting earthquake ground motions. - Multimedia
- Publications
Filter Total Items: 15
Limits to coseismic landslides triggered by Cascadia Subduction Zone earthquakes
Landslides are a significant hazard and dominant feature throughout the landscape of the Pacific Northwest. However, the hazard and risk posed by coseismic landslides triggered by great Cascadia Subduction Zone (CSZ) earthquakes is highly uncertain due to a lack of local and global data. Despite a wealth of other geologic evidence for past earthquakes on the Cascadia Subduction Zone, no landslidesAuthorsAlex R. R. Grant, William Struble, Sean Richard LaHusenRegional-scale liquefaction analyses
Regional-scale liquefaction hazard analyses are necessary for resilience planning and prioritization of seismic upgrades for critical distributed infrastructure such as levees, pipelines, roadways, and electrical transmission facilities. Two approaches are often considered for liquefaction hazard analysis of distributed infrastructure: (1) conventional, site-specific probe or borehole-based analysAuthorsMichael W. Greenfield, Alex R. R. GrantChanges in liquefaction severity in the San Francisco Bay Area with sea-level rise
This paper studies the impacts of sea-level rise on liquefaction triggering and severity around the San Francisco Bay Area, California, for the M 7.0 “HayWired” earthquake scenario along the Hayward fault. This work emerged from stakeholder engagement for the US Geological Survey releases of the HayWired earthquake scenario and the Coastal Storm Modeling System projects, in which local planners anAuthorsAlex R. R. Grant, Anne Wein, Kevin M. Befus, Juliette Finzi-Hart, Mike Frame, Rachel Volentine, Patrick L. Barnard, Keith L. KnudsenThe 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 boundaAuthorsEgill 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 ValkaniotisSite response, basin amplification, and earthquake stress drops in the Portland, Oregon area
Site response, sedimentary basin amplification, and earthquake stress drops for the Portland, Oregon area were determined using accelerometer recordings at 16 sites of 10 local earthquakes with MDMD 2.6–4.0. A nonlinear inversion was applied to calculate site response (0.5–10 Hz), corner frequencies, and seismic moments from the Fourier spectra of the earthquakes. Site amplifications at lower freqAuthorsArthur Frankel, Alex R. R. GrantEnsemble ShakeMaps for magnitude 9 earthquakes on the Cascadia Subduction Zone
We develop ensemble ShakeMaps for various magnitude 9 (MM 9) earthquakes on the Cascadia megathrust. Ground‐shaking estimates are based on 30 MM 9 Cascadia earthquake scenarios, which were selected using a logic‐tree approach that varied the hypocenter location, down‐dip rupture limit, slip distribution, and location of strong‐motion‐generating subevents. In a previous work, Frankel et al. (2018)AuthorsErin Wirth, Alex R. R. Grant, Nasser A. Marafi, Arthur FrankelA generic soil velocity model that accounts for near-surface conditions and deeper geologic structure
Near-surface soil conditions can significantly alter the amplitude and frequency content of incoming ground motions – often with profound consequences for the built environment – and are thus important inputs to any ground-motion prediction. Previous soil-velocity models (SVM) have predicted shear-wave velocity profiles based on the time-averaged shear-wave velocity in the upper 30 m (VS30). ThisAuthorsNasser A. Marafi, Alex R. R. Grant, Brett W. Maurer, Gunjan Rateria, Marc O Eberhard, Jeff W BermanRainfall triggers more deep-seated landslides than Cascadia earthquakes in the Oregon Coast Range, USA
The coastal Pacific Northwest USA hosts thousands of deep-seated landslides. Historic landslides have primarily been triggered by rainfall, but the region is also prone to large earthquakes on the 1100-km-long Cascadia Subduction Zone megathrust. Little is known about the number of landslides triggered by these earthquakes because the last magnitude 9 rupture occurred in 1700 CE. Here, we map 9938AuthorsSean R LaHusen, Alison R Duvall, Adam M. Booth, Alex R. R. Grant, Benjamin A Mishkin, David R. Montgomery, William Struble, Joshua J. Roering, Joseph WartmanGround failure triggered by shaking during the November 30, 2018, magnitude 7.1 Anchorage, Alaska, earthquake
We developed an initial inventory of ground failure features from the November 30, 2018, magnitude 7.1 Anchorage earthquake. This inventory of 153 features is from ground-based observations soon after the earthquake (December 5–10) that include the presence or absence of liquefaction, landslides, and individual crack traces of lateral spreads and incipient landslides. This is not a complete inventAuthorsAlex R. R. Grant, Randall W. Jibson, Robert C. Witter, Kate E. Allstadt, Eric M. Thompson, Adrian M. BenderProbabilistic regional-scale liquefaction triggering modeling using 3D Gaussian processes
Liquefaction is a major cause of coseismic damages, occurring irregularly over hundreds or thousands of square kilometers in large earthquakes. Large variations in the extent and location of liquefaction have been observed in recent earthquakes, motivating the need for prediction methods that consider the spatial heterogeneity of geologic deposits at a regional scale. Contemporary regional-scale lAuthorsMichael Greenfield, Alex R. R. GrantUSGS near-real-time products-and their use-for the 2018 Anchorage earthquake
In the minutes to hours after a major earthquake, such as the recent 2018 Mw 7.1 Anchorage event, the U.S. Geological Survey (USGS) produces a suite of interconnected earthquake products that provides diverse information ranging from basic earthquake source parameters to loss estimates. The 2018 Anchorage earthquake is the first major domestic earthquake to occur since several new USGS products haAuthorsEric M. Thompson, Sara McBride, Gavin P. Hayes, Kate E. Allstadt, Lisa Wald, David J. Wald, Keith L. Knudsen, Charles Worden, Kristin Marano, Randall W. Jibson, Alex R. R. GrantGround failure from the Anchorage, Alaska, earthquake of 30 November 2018
Investigation of ground failure triggered by the 2018 MwMw 7.1 Anchorage earthquake showed that landslides, liquefaction, and ground cracking all occurred and caused significant damage. Shallow rock falls and rock slides were the most abundant types of landslides, but they occurred in smaller numbers than global models that are based on earthquake magnitude predict; this might result from the 2018AuthorsRandall W. Jibson, Alex R. R. Grant, Robert C. Witter, Kate E. Allstadt, Eric M. Thompson, Adrian Bender - Web Tools
Liquefaction and Sea-Level Rise
USGS scientists published a storymap explaining the impacts of sea-level rise on liquefaction severity around the San Francisco Bay Area, California for the magnitude 7.0 ‘HayWired’ earthquake scenario along the Hayward Fault.
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