Robert W Graves
Science and Products
The science, engineering applications, and policy implications of simulation-based PSHA
We summarize scientific methods for developing probabilistic seismic hazard assessments from 3-D earthquake ground motion simulations, describe current use of simulated ground motions for engineering applications, and discuss on-going efforts to incorporate these effects in the U.S. national seismic hazard model. The 3-D simulations provide...
Moschetti, Morgan P.; Chang, Sandra P.; Crouse, C.B; Frankel, Arthur; Graves, Robert; Puangnak, H; Luco, Nicolas; Goulet, Christine A.; Rezaeian, Sanaz; Shumway, Allison; Powers, Peter M.; Petersen, Mark D.; Callaghan, Scott; Jordan, T.H.; Milner, Kevin R. Integrate urban‐scale seismic hazard analyses with the U.S. National Seismic Hazard Model
For more than 20 yrs, damage patterns and instrumental recordings have highlighted the influence of the local 3D geologic structure on earthquake ground motions (e.g., M">MM 6.7 Northridge, California, Gao et al., 1996; M">MM 6.9 Kobe, Japan, Kawase, 1996; M">MM 6.8 Nisqually,...
Moschetti, Morgan P.; Luco, Nicolas; Frankel, Arthur; Petersen, Mark D.; Aagaard, Brad T.; Baltay, Annemarie S.; Blanpied, Michael; Boyd, Oliver S.; Briggs, Richard W.; Gold, Ryan D.; Graves, Robert; Hartzell, Stephen H.; Rezaeian, Sanaz; Stephenson, William J.; Wald, David J.; Williams, Robert A.; Withers, Kyle
U.S. Geological Survey National Strong-Motion Project strategic plan, 2017–22
The mission of the National Strong-Motion Project is to provide measurements of how the ground and built environment behave during earthquake shaking to the earthquake engineering community, the scientific community, emergency managers, public agencies, industry, media, and other users for the following purposes: Improving engineering evaluations...
Aagaard, Brad T.; Celebi, Mehmet; Gee, Lind; Graves, Robert; Jaiswal, Kishor; Kalkan, Erol; Knudsen, Keith L.; Luco, Nicolas; Smith, James; Steidl, Jamison; Stephens, Christopher D. Performance of Irikura recipe rupture model generator in earthquake ground motion simulations with Graves and Pitarka hybrid approach
We analyzed the performance of the Irikura and Miyake (Pure and Applied Geophysics 168(2011):85–104, 2011) (IM2011) asperity-based kinematic rupture model generator, as implemented in the hybrid broadband ground motion simulation methodology of Graves and Pitarka (Bulletin of the Seismological Society of America 100(5A):2095–2123, 2010), for...
Pitarka, Arben; Graves, Robert; Irikura, Kojiro; Miyake, Hiroe; Rodgers, Arthur Subsurface geometry of the San Andreas fault in southern California: Results from the Salton Seismic Imaging Project (SSIP) and strong ground motion expectations
The San Andreas fault (SAF) is one of the most studied strike‐slip faults in the world; yet its subsurface geometry is still uncertain in most locations. The Salton Seismic Imaging Project (SSIP) was undertaken to image the structure surrounding the SAF and also its subsurface geometry. We present SSIP studies at two locations in the Coachella...
Fuis, Gary S.; Bauer, Klaus; Goldman, Mark R.; Ryberg, Trond; Langenheim, Victoria; Scheirer, Daniel S.; Rymer, Michael J.; Stock, Joann M.; Hole, John A.; Catchings, Rufus D.; Graves, Robert; Aagaard, Brad T. Evidence for strong lateral seismic velocity variation in the lower crust and upper mantle beneath the California margin
Regional seismograms from earthquakes in Northern California show a systematic difference in arrival times across Southern California where long period (30–50 seconds) SH waves arrive up to 15 seconds earlier at stations near the coast compared with sites towards the east at similar epicentral distances. We attribute this time difference to...
Lai, Voon; Graves, Robert; Wei, Shengji; Helmberger, Don Kinematic ground motion simulations on rough faults including effects of 3D stochastic velocity perturbations
We describe a methodology for generating kinematic earthquake ruptures for use in 3D ground‐motion simulations over the 0–5 Hz frequency band. Our approach begins by specifying a spatially random slip distribution that has a roughly wavenumber‐squared fall‐off. Given a hypocenter, the rupture speed is specified to average about 75%–80% of the...
Graves, Robert; Pitarka, Arben The 2014 Mw6.1 South Napa Earthquake: A unilateral rupture with shallow asperity and rapid afterslip
The Mw6.1 South Napa earthquake occurred near Napa, California on August 24, 2014 (UTC), and was the largest inland earthquake in Northern California since the 1989 Mw6.9 Loma Prieta earthquake. The first report of the earthquake from the Northern California Earthquake Data Center (NCEDC) indicates a hypocentral depth of 11.0km with longitude and...
Wei, Shengji; Barbot, Sylvain; Graves, Robert; Lienkaemper, James J.; Wang, Teng; Hudnut, Kenneth W.; Fu, Yuning; Helmberger, Don Refinements to the Graves and Pitarka (2010) Broadband Ground Motion Simulation Method
This brief article describes refinements to the Graves and Pitarka (2010) broadband ground motion simulation methodology (GP2010 hereafter) that have been implemented in version 14.3 of the SCEC Broadband Platform (BBP). The updated version of our method on the current SCEC BBP is referred to as GP14.3. Our simulation technique is a hybrid...
Graves, Robert; Arben Pitarka Ground motion-simulations of 1811-1812 New Madrid earthquakes, central United States
We performed a suite of numerical simulations based on the 1811–1812 New Madrid seismic zone (NMSZ) earthquakes, which demonstrate the importance of 3D geologic structure and rupture directivity on the ground‐motion response throughout a broad region of the central United States (CUS) for these events. Our simulation set consists of 20...
Ramirez-Guzman, L.; Graves, Robert; Olsen, Kim B.; Boyd, Oliver S.; Cramer, Chris H.; Hartzell, Stephen H.; Ni, Sidao; Somerville, Paul G.; Williams, Robert; Zhong, Jinquan Adding fling effects to processed ground‐motion time histories
Fling is the engineering term for the effects of the permanent tectonic offset, caused by a rupturing fault in the recorded ground motions near the fault. It is expressed by a one‐sided pulse in ground velocity and a nonzero final displacement at the end of shaking. Standard processing of earthquake time histories removes some of the fling effects...
Kamai, Ronnie; Abrahamson, Norman A.; Graves, Robert CyberShake-derived ground-motion prediction models for the Los Angeles region with application to earthquake early warning
Real-time applications such as earthquake early warning (EEW) typically use empirical ground-motion prediction equations (GMPEs) along with event magnitude and source-to-site distances to estimate expected shaking levels. In this simplified approach, effects due to finite-fault geometry, directivity and site and basin response are often...
Bose, Maren; Graves, Robert; Gill, David; Callaghan, Scott; Maechling, Phillip J.