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Directivity models produced for the Next Generation Attenuation West 2 (NGA-West 2) project

Five new directivity models are being developed for the NGA-West 2 project. All are based on the NGA-West 2 data base, which is considerably expanded from the original NGA-West data base, containing about 3,000 more records from earthquakes having finite-fault rupture models. All of the new directivity models have parameters based on fault dimension in km, not normalized fault dimension. This feat
Authors
Paul A. Spudich, Jennie Watson-Lamprey, Paul G. Somerville, Jeff Bayless, Shrey Shahi, Jack W. Baker, Badie Rowshandel, Brian Chiou

Design and implementation of a structural health monitoring and alerting system for hospital buildings in the United States

This paper describes the current progress in the development of a structural health monitoring and alerting system to meet the needs of the U.S. Department of Veterans Affairs to monitor hospital buildings instrumented in high and very high seismic hazard regions in the U.S. The system, using the measured vibration data, is primarily designed for post-earthquake condition assessment of the buildin
Authors
Hasan S. Ulusoy, Erol Kalkan, Jon Peter B. Fletcher, Paul A. Friberg, W. K. Leith, Krishna Banga

Estimating rate uncertainty with maximum likelihood: differences between power-law and flicker–random-walk models

Recent studies have documented that global positioning system (GPS) time series of position estimates have temporal correlations which have been modeled as a combination of power-law and white noise processes. When estimating quantities such as a constant rate from GPS time series data, the estimated uncertainties on these quantities are more realistic when using a noise model that includes tempor
Authors
John O. Langbein

Designs and test results for three new rotational sensors

We discuss the designs and testing of three rotational seismometer prototypes developed at the Institute of Geophysics, Academy of Sciences (Prague, Czech Republic). Two of these designs consist of a liquid-filled toroidal tube with the liquid as the proof mass and providing damping; we tested the piezoelectric and pressure transduction versions of this torus. The third design is a wheel-shaped so
Authors
P. Jedlicka, J.T. Kozak, J.R. Evans, C. R. Hutt

Helping safeguard Veterans Affairs' hospital buildings by advanced earthquake monitoring

In collaboration with the U.S. Department of Veterans Affairs (VA), the National Strong Motion Project of the U.S. Geological Survey has recently installed sophisticated seismic systems that will monitor the structural integrity of hospital buildings during earthquake shaking. The new systems have been installed at more than 20 VA medical campuses across the country. These monitoring systems, whic
Authors
Erol Kalkan, Krishna Banga, Hasan S. Ulusoy, Jon Peter B. Fletcher, William S. Leith, James L. Blair

Turbidite event history—Methods and implications for Holocene paleoseismicity of the Cascadia subduction zone

Turbidite systems along the continental margin of Cascadia Basin from Vancouver Island, Canada, to Cape Mendocino, California, United States, have been investigated with swath bathymetry; newly collected and archive piston, gravity, kasten, and box cores; and accelerator mass spectrometry radiocarbon dates. The purpose of this study is to test the applicability of the Holocene turbidite record as
Authors
Chris Goldfinger, C. Hans Nelson, Ann E. Morey, Joel E. Johnson, Jason R. Patton, Eugene B. Karabanov, Julia Gutierrez-Pastor, Andrew T. Eriksson, Eulalia Gracia, Gita Dunhill, Randolph J. Enkin, Audrey Dallimore, Tracy Vallier

Initial assessment of the intensity distribution of the 2011 Mw5.8 Mineral, Virginia, earthquake

The intensity data collected by the U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) Website (USGS, DYFI; http://earthquake.usgs.gov/earthquakes/dyfi/events/se/082311a/us/index.html, last accessed Sept 2011) for the Mw5.8 Mineral, Virginia, earthquake, are unprecedented in their spatial richness and geographical extent. More than 133,000 responses were received during the first week followi
Authors
Susan E. Hough

Source parameters of microearthquakes on an interplate asperity off Kamaishi, NE Japan over two earthquake cycles

We have estimated the source parameters of interplate earthquakes in an earthquake cluster off Kamaishi, NE Japan over two cycles of M~ 4.9 repeating earthquakes. The M~ 4.9 earthquake sequence is composed of nine events that occurred since 1957 which have a strong periodicity (5.5 ± 0.7 yr) and constant size (M4.9 ± 0.2), probably due to stable sliding around the source area (asperity). Using P-
Authors
Naoki Uchida, Toru Matsuzawa, William L. Ellsworth, Kazutoshi Imanishi, Kouhei Shimamura, Akira Hasegawa

Probabilistic estimates of surface coseismic slip and afterslip for Hayward fault earthquakes

We examine the partition of long‐term geologic slip on the Hayward fault into interseismic creep, coseismic slip, and afterslip. Using Monte Carlo simulations, we compute expected coseismic slip and afterslip at three alinement array sites for Hayward fault earthquakes with nominal moment magnitudes ranging from about 6.5 to 7.1. We consider how interseismic creep might affect the coseismic slip d
Authors
Brad T. Aagaard, James J. Lienkaemper, David P. Schwartz

Linear complementarity formulation for 3D frictional sliding problems

Frictional sliding on quasi-statically deforming faults and fractures can be modeled efficiently using a linear complementarity formulation. We review the formulation in two dimensions and expand the formulation to three-dimensional problems including problems of orthotropic friction. This formulation accurately reproduces analytical solutions to static Coulomb friction sliding problems. The formu
Authors
J. Ole Kaven, Stephen H. Hickman, Nicholas C. Davatzes, Ovunc Mutlu

Correlation of clayey gouge in a surface exposure of the San Andreas fault with gouge at depth from SAFOD: Implications for the role of serpentinite in fault mechanics

Magnesium-rich clayey gouge similar to that comprising the two actively creeping strands of the San Andreas Fault in drill core from the San Andreas Fault Observatory at Depth (SAFOD) has been identified in a nearby outcrop of serpentinite within the fault zone at Nelson Creek. Each occurrence of the gouge consists of porphyroclasts of serpentinite and sedimentary rocks dispersed in a fine-grained
Authors
Diane E. Moore, Michael J. Rymer

Logs and data from trenches across and near the Green Valley Fault at the Mason Road site, Fairfield, Solano County, California, 2006-2009

The primary purpose of this report is to provide drafted field logs of exploratory trenches excavated across the Green Valley Fault in 2007 and 2009 that show evidence for four surface rupturing earthquakes in the past one thousand years. The site location and site detail are shown on sheet 1. The trench logs are shown on sheets 1, 2, and 3. We also provide radiocarbon laboratory dates used for ch
Authors
James J. Lienkaemper, Robert R. Sickler, Shannon Mahan, Johnathan Brown, Liam M. Reidy, Mindy A. Kimball