Robert W Graves
Rob Graves is a geophysicist in the Earthquake Hazards Program.
Science and Products
Filter Total Items: 46
Broadband ground-motion simulation using a hybrid approach
This paper describes refinements to the hybrid broadband ground-motion simulation methodology of Graves and Pitarka (2004), which combines a deterministic approach at low frequencies (f< 1 Hz) with a semistochastic approach at high frequencies (f> 1 Hz). In our approach, fault rupture is represented kinematically and incorporates spatial heterogeneity in slip, rupture speed, and rise time. The pre
Authors
R.W. Graves, A. Pitarka
The ShakeOut earthquake scenario: Verification of three simulation sets
This paper presents a verification of three simulations of the ShakeOut scenario, an Mw 7.8 earthquake on a portion of the San Andreas fault in southern California, conducted by three different groups at the Southern California Earthquake Center using the SCEC Community Velocity Model for this region. We conducted two simulations using the finite difference method, and one by the finite element me
Authors
J. Bielak, R.W. Graves, K.B. Olsen, R. Taborda, L. Ramirez-Guzman, S.M. Day, G.P. Ely, D. Roten, T.H. Jordan, P.J. Maechling, J. Urbanic, Y. Cui, G. Juve
Ground-motion modeling of the 1906 San Francisco earthquake, part I: Validation using the 1989 Loma Prieta earthquake
We compute ground motions for the Beroza (1991) and Wald et al. (1991) source models of the 1989 magnitude 6.9 Loma Prieta earthquake using four different wave-propagation codes and recently developed 3D geologic and seismic velocity models. In preparation for modeling the 1906 San Francisco earthquake, we use this well-recorded earthquake to characterize how well our ground-motion simulations rep
Authors
Brad T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R.W. Graves, S. Harmsen, S. Hartzell, S. Larsen, M.L. Zoback
Broadband simulations for Mw 7.8 southern san andreas earthquakes: Ground motion sensitivity to rupture speed
Using the high-performance computing resources of the Southern California Earthquake Center, we simulate broadband (0-10 Hz) ground motions for three Mw 7.8 rupture scenarios of the southern San Andreas fault. The scenarios incorporate a kinematic rupture description with the average rupture speed along the large slip portions of the fault set at 0.96, 0.89, and 0.84 times the local shear wave vel
Authors
R.W. Graves, Brad T. Aagaard, K.W. Hudnut, L.M. Star, J.P. Stewart, T.H. Jordan
Ground-motion modeling of the 1906 San Francisco Earthquake, part II: Ground-motion estimates for the 1906 earthquake and scenario events
We estimate the ground motions produce by the 1906 San Francisco earthquake making use of the recently developed Song et al. (2008) source model that combines the available geodetic and seismic observations and recently constructed 3D geologic and seismic velocity models. Our estimates of the ground motions for the 1906 earthquake are consistent across five ground-motion modeling groups employing
Authors
Brad T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R.W. Graves, S. Harmsen, S. Hartzell, S. Larsen, K. McCandless, S. Nilsson, N.A. Petersson, A. Rodgers, B. Sjogreen, M.L. Zoback
Observed and simulated ground motions in the San Bernardino basin region for the Hector Mine, California, earthquake
During the MW 7.1 Hector Mine earthquake, peak ground velocities recorded at sites in the central San Bernardino basin region were up to 2 times larger and had significantly longer durations of strong shaking than sites just outside the basin. To better understand the effects of 3D structure on the long-period ground-motion response in this region, we have performed finite-difference simulations f
Authors
R.W. Graves, D.J. Wald
Resolution analysis of finite fault source inversion using one- and three-dimensional Green's functions 2. Combining seismic and geodetic data
Using numerical tests for a prescribed heterogeneous earthquake slip distribution, we examine the importance of accurate Green's functions (GF) for finite fault source inversions which rely on coseismic GPS displacements and leveling line uplift alone and in combination with near-source strong ground motions. The static displacements, while sensitive to the three-dimensional (3-D) structure, are l
Authors
D.J. Wald, R.W. Graves
Resolution analysis of finite fault source inversion using one- and three-dimensional Green's functions 1. Strong motions
We develop a methodology to perform finite fault source inversions from strong motion data using Green's functions (GFs) calculated for a three-dimensional (3-D) velocity structure. The 3-D GFs are calculated numerically by inserting body forces at each of the strong motion sites and then recording the resulting strains along the target fault surface. Using reciprocity, these GFs can be recombined
Authors
R.W. Graves, D.J. Wald
The seismic response of the Los Angeles basin, California
Using strong-motion data recorded in the Los Angeles region from the 1992 (Mw 7.3) Landers earthquake, we have tested the accuracy of existing three-dimensional (3D) velocity models on the simulation of long-period (≧2 sec) ground motions in the Los Angeles basin and surrounding San Fernando and San Gabriel Valleys. First, the overall pattern and degree of long-period excitation of the basins were
Authors
D.J. Wald, R.W. Graves
The Loma Prieta, California, Earthquake of October 17, 1989: Strong ground motion
Strong ground motion generated by the Loma Prieta, Calif., earthquake (MS~7.1) of October 17, 1989, resulted in at least 63 deaths, more than 3,757 injuries, and damage estimated to exceed $5.9 billion. Strong ground motion severely damaged critical lifelines (freeway overpasses, bridges, and pipelines), caused severe damage to poorly constructed buildings, and induced a significant number of grou
Authors
Roger D. Borcherdt, A. Gerald Brady, A.F. Shakal, V.F. Cormier, Wei-Jou Su, Jeffry L. Stevens, Steven M. Day, John E. Vidale, Ornella Bonamassa, Paul G. Somerville, Nancy F. Smith, Robert Graves, Gary Glassmoyer, Kyle Rollins, Michael D. Mchood, Roman D. Hryciw, Matthew Homolka, Scott E. Shewbridge, Harvey Carlisle, Nicholas Sitar, Rodrigo Salgado, Pedro de Alba, J. Benoit, Daniel G. Pass, John Carter, T. Leslie Youd, E. H. Field, Susan E. Hough, K.H. Jacob, Paul A. Friberg, Arthur Frankel, R. Busby, Robert A. Williams, Edward Cranswick, Kenneth W. King, Grant T. Lindley, Ralph J. Archuleta, Janice M. Murphy, Steven G. Wesnousky
Science and Products
Filter Total Items: 46
Broadband ground-motion simulation using a hybrid approach
This paper describes refinements to the hybrid broadband ground-motion simulation methodology of Graves and Pitarka (2004), which combines a deterministic approach at low frequencies (f< 1 Hz) with a semistochastic approach at high frequencies (f> 1 Hz). In our approach, fault rupture is represented kinematically and incorporates spatial heterogeneity in slip, rupture speed, and rise time. The pre
Authors
R.W. Graves, A. Pitarka
The ShakeOut earthquake scenario: Verification of three simulation sets
This paper presents a verification of three simulations of the ShakeOut scenario, an Mw 7.8 earthquake on a portion of the San Andreas fault in southern California, conducted by three different groups at the Southern California Earthquake Center using the SCEC Community Velocity Model for this region. We conducted two simulations using the finite difference method, and one by the finite element me
Authors
J. Bielak, R.W. Graves, K.B. Olsen, R. Taborda, L. Ramirez-Guzman, S.M. Day, G.P. Ely, D. Roten, T.H. Jordan, P.J. Maechling, J. Urbanic, Y. Cui, G. Juve
Ground-motion modeling of the 1906 San Francisco earthquake, part I: Validation using the 1989 Loma Prieta earthquake
We compute ground motions for the Beroza (1991) and Wald et al. (1991) source models of the 1989 magnitude 6.9 Loma Prieta earthquake using four different wave-propagation codes and recently developed 3D geologic and seismic velocity models. In preparation for modeling the 1906 San Francisco earthquake, we use this well-recorded earthquake to characterize how well our ground-motion simulations rep
Authors
Brad T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R.W. Graves, S. Harmsen, S. Hartzell, S. Larsen, M.L. Zoback
Broadband simulations for Mw 7.8 southern san andreas earthquakes: Ground motion sensitivity to rupture speed
Using the high-performance computing resources of the Southern California Earthquake Center, we simulate broadband (0-10 Hz) ground motions for three Mw 7.8 rupture scenarios of the southern San Andreas fault. The scenarios incorporate a kinematic rupture description with the average rupture speed along the large slip portions of the fault set at 0.96, 0.89, and 0.84 times the local shear wave vel
Authors
R.W. Graves, Brad T. Aagaard, K.W. Hudnut, L.M. Star, J.P. Stewart, T.H. Jordan
Ground-motion modeling of the 1906 San Francisco Earthquake, part II: Ground-motion estimates for the 1906 earthquake and scenario events
We estimate the ground motions produce by the 1906 San Francisco earthquake making use of the recently developed Song et al. (2008) source model that combines the available geodetic and seismic observations and recently constructed 3D geologic and seismic velocity models. Our estimates of the ground motions for the 1906 earthquake are consistent across five ground-motion modeling groups employing
Authors
Brad T. Aagaard, T. M. Brocher, D. Dolenc, D. Dreger, R.W. Graves, S. Harmsen, S. Hartzell, S. Larsen, K. McCandless, S. Nilsson, N.A. Petersson, A. Rodgers, B. Sjogreen, M.L. Zoback
Observed and simulated ground motions in the San Bernardino basin region for the Hector Mine, California, earthquake
During the MW 7.1 Hector Mine earthquake, peak ground velocities recorded at sites in the central San Bernardino basin region were up to 2 times larger and had significantly longer durations of strong shaking than sites just outside the basin. To better understand the effects of 3D structure on the long-period ground-motion response in this region, we have performed finite-difference simulations f
Authors
R.W. Graves, D.J. Wald
Resolution analysis of finite fault source inversion using one- and three-dimensional Green's functions 2. Combining seismic and geodetic data
Using numerical tests for a prescribed heterogeneous earthquake slip distribution, we examine the importance of accurate Green's functions (GF) for finite fault source inversions which rely on coseismic GPS displacements and leveling line uplift alone and in combination with near-source strong ground motions. The static displacements, while sensitive to the three-dimensional (3-D) structure, are l
Authors
D.J. Wald, R.W. Graves
Resolution analysis of finite fault source inversion using one- and three-dimensional Green's functions 1. Strong motions
We develop a methodology to perform finite fault source inversions from strong motion data using Green's functions (GFs) calculated for a three-dimensional (3-D) velocity structure. The 3-D GFs are calculated numerically by inserting body forces at each of the strong motion sites and then recording the resulting strains along the target fault surface. Using reciprocity, these GFs can be recombined
Authors
R.W. Graves, D.J. Wald
The seismic response of the Los Angeles basin, California
Using strong-motion data recorded in the Los Angeles region from the 1992 (Mw 7.3) Landers earthquake, we have tested the accuracy of existing three-dimensional (3D) velocity models on the simulation of long-period (≧2 sec) ground motions in the Los Angeles basin and surrounding San Fernando and San Gabriel Valleys. First, the overall pattern and degree of long-period excitation of the basins were
Authors
D.J. Wald, R.W. Graves
The Loma Prieta, California, Earthquake of October 17, 1989: Strong ground motion
Strong ground motion generated by the Loma Prieta, Calif., earthquake (MS~7.1) of October 17, 1989, resulted in at least 63 deaths, more than 3,757 injuries, and damage estimated to exceed $5.9 billion. Strong ground motion severely damaged critical lifelines (freeway overpasses, bridges, and pipelines), caused severe damage to poorly constructed buildings, and induced a significant number of grou
Authors
Roger D. Borcherdt, A. Gerald Brady, A.F. Shakal, V.F. Cormier, Wei-Jou Su, Jeffry L. Stevens, Steven M. Day, John E. Vidale, Ornella Bonamassa, Paul G. Somerville, Nancy F. Smith, Robert Graves, Gary Glassmoyer, Kyle Rollins, Michael D. Mchood, Roman D. Hryciw, Matthew Homolka, Scott E. Shewbridge, Harvey Carlisle, Nicholas Sitar, Rodrigo Salgado, Pedro de Alba, J. Benoit, Daniel G. Pass, John Carter, T. Leslie Youd, E. H. Field, Susan E. Hough, K.H. Jacob, Paul A. Friberg, Arthur Frankel, R. Busby, Robert A. Williams, Edward Cranswick, Kenneth W. King, Grant T. Lindley, Ralph J. Archuleta, Janice M. Murphy, Steven G. Wesnousky