Publications
Filter Total Items: 2585
A methodology for post-mainshock probabilistic assessment of building collapse risk
This paper presents a methodology for post-earthquake probabilistic risk (of damage) assessment that we propose in order to develop a computational tool for automatic or semi-automatic assessment. The methodology utilizes the same so-called risk integral which can be used for pre-earthquake probabilistic assessment. The risk integral couples (i) ground motion hazard information for the location of
Authors
N. Luco, M.C. Gerstenberger, S.R. Uma, H. Ryu, A.B. Liel, M. Raghunandan
Long-period earthquake simulations in the Wasatch Front, UT: misfit characterization and ground motion estimates
In this research we characterize the goodness-of-fit between observed and synthetic seismograms from three small magnitude (M3.6-4.5) earthquakes in the region using the Wasatch Front community velocity model (WCVM) in order to determine the ability of the WCVM to predict earthquake ground motions for scenario earthquake modeling efforts. We employ the goodness-of-fit algorithms and criteria of Ol
Authors
Morgan P. Moschetti, Leonardo Ramírez-Guzmán
Understanding the amplitudes of noise correlation measurements
Cross correlation of ambient seismic noise is known to result in time series from which station-station travel-time measurements can be made. Part of the reason that these cross-correlation travel-time measurements are reliable is that there exists a theoretical framework that quantifies how these travel times depend on the features of the ambient noise. However, corresponding theoretical results
Authors
Victor C. Tsai
Rapid Source Characterization of the 2011 Mw 9.0 off the Pacific coast of Tohoku Earthquake
On March 11th, 2011, a moment magnitude 9.0 earthquake struck off the coast of northeast Honshu, Japan, generating what may well turn out to be the most costly natural disaster ever. In the hours following the event, the U.S. Geological Survey National Earthquake Information Center led a rapid response to characterize the earthquake in terms of its location, size, faulting source, shaking and slip
Authors
Gavin P. Hayes
Seismic hazard maps for Haiti
We have produced probabilistic seismic hazard maps of Haiti for peak ground acceleration and response spectral accelerations that include the hazard from the major crustal faults, subduction zones, and background earthquakes. The hazard from the Enriquillo-Plantain Garden, Septentrional, and Matheux-Neiba fault zones was estimated using fault slip rates determined from GPS measurements. The hazard
Authors
Arthur Frankel, Stephen Harmsen, Charles Mueller, Eric Calais, Jennifer Haase
Scientific drilling into the San Andreas Fault Zone - an overview of SAFOD's first five years
The San Andreas Fault Observatory at Depth (SAFOD) was drilled to study the physical and chemical processes controlling faulting and earthquake generation along an active, plate-bounding fault at depth. SAFOD is located near Parkfield, California and penetrates a section of the fault that is moving due to a combination of repeating microearthquakes and fault creep. Geophysical logs define the San
Authors
Mark Zoback, Stephen Hickman, William Ellsworth
Representation of bidirectional ground motions for design spectra in building codes
The 2009 NEHRP Provisions modified the definition of horizontal ground motion from the geometric mean of spectral accelerations for two components to the peak response of a single lumped mass oscillator regardless of direction. These maximum-direction (MD) ground motions operate under the assumption that the dynamic properties of the structure (e.g., stiffness, strength) are identical in all direc
Authors
Jonathan P. Stewart, Norman A. Abrahamson, Gail M. Atkinson, Jack W. Beker, David M. Boore, Yousef Bozorgnia, Kenneth W. Campbell, Craig D. Comartin, I.M. Idriss, Marshall Lew, Michael Mehrain, Jack P. Moehle, Farzad Naeim, Thomas A. Sabol
Regional correlations of VS30 averaged over depths less than and greater than 30 meters
Using velocity profiles from sites in Japan, California, Turkey, and Europe, we find that the time-averaged shear-wave velocity to 30 m (VS30), used as a proxy for site amplification in recent ground-motion prediction equations (GMPEs) and building codes, is strongly correlated with average velocities to depths less than 30 m (VSz, with z being the averaging depth). The correlations for sites in J
Authors
David M. Boore, Eric M. Thompson, Héloïse Cadet
Estimating unknown input parameters when implementing the NGA ground-motion prediction equations in engineering practice
The ground-motion prediction equations (GMPEs) developed as part of the Next Generation Attenuation of Ground Motions (NGA-West) project in 2008 are becoming widely used in seismic hazard analyses. However, these new models are considerably more complicated than previous GMPEs, and they require several more input parameters. When employing the NGA models, users routinely face situations in which s
Authors
James Kaklamanos, Laurie G. Baise, David M. Boore
Using the 2011 Mw9.0 Tohoku earthquake to test the Coulomb stress triggering hypothesis and to calculate faults brought closer to failure
The 11 March 2011 Tohoku Earthquake provides an unprecedented test of the extent to which Coulomb stress transfer governs the triggering of aftershocks. During 11-31 March, there were 177 aftershocks with focal mechanisms, and so the Coulomb stress change imparted by the rupture can be resolved on the aftershock nodal planes to learn whether they were brought closer to failure. Numerous source mod
Authors
Shinji Toda, Jian Lin, Ross S. Stein
Testing long-period ground-motion simulations of scenario earthquakes using the Mw 7.2 El Mayor-Cucapah mainshock: Evaluation of finite-fault rupture characterization and 3D seismic velocity models
Using a suite of five hypothetical finite-fault rupture models, we test the ability of long-period (T>2.0 s) ground-motion simulations of scenario earthquakes to produce waveforms throughout southern California consistent with those recorded during the 4 April 2010 Mw 7.2 El Mayor-Cucapah earthquake. The hypothetical ruptures are generated using the methodology proposed by Graves and Pitarka (2010
Authors
Robert W. Graves, Brad T. Aagaard
Liquefaction probability curves for surficial geologic deposits
Liquefaction probability curves that predict the probability of surface manifestations of earthquake-induced liquefaction are developed for 14 different types of surficial geologic units. The units consist of alluvial fan, beach ridge, river delta topset and foreset beds, eolian dune, point bar, flood basin, natural river and alluvial fan levees, abandoned river channel, deep-water lake, lagoonal,
Authors
Thomas L. Holzer, Thomas E. Noce, Michael J. Bennett