Publications
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Aftershock seismicity of the 2010 Maule Mw=8.8 Chile, earthquake: Correlation between co-seismic slip models and aftershock distribution?
The 27 February 2010 Maule, Chile (Mw=8.8) earthquake is one of the best instrumentally observed subduction zone megathrust events. Here we present locations, magnitudes and cumulative equivalent moment of the first -2 months of aftershocks, recorded on a temporary network deployed within 2 weeks of the occurrence of the mainshock. Using automatically-determined onset times and a back projection a
Authors
A. Rietbrock, I. Ryder, G. Hayes, C. Haberland, D. Comte, S. Roecker
Including foreshocks and aftershocks in time-independent probabilistic seismic hazard analyses
Time‐independent probabilistic seismic‐hazard analysis treats each source as being temporally and spatially independent; hence foreshocks and aftershocks, which are both spatially and temporally dependent on the mainshock, are removed from earthquake catalogs. Yet, intuitively, these earthquakes should be considered part of the seismic hazard, capable of producing damaging ground motions. In this
Authors
Oliver S. Boyd
Relative azimuth inversion by way of damped maximum correlation estimates
Horizontal seismic data are utilized in a large number of Earth studies. Such work depends on the published orientations of the sensitive axes of seismic sensors relative to true North. These orientations can be estimated using a number of different techniques: SensOrLoc (Sensitivity, Orientation and Location), comparison to synthetics (Ekstrom and Busby, 2008), or by way of magnetic compass. Curr
Authors
A. T. Ringler, J.D. Edwards, C. R. Hutt, F. Shelly
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
Spatial aspects of building and population exposure data and their implications for global earthquake exposure modeling
This paper discusses spatial aspects of the global exposure dataset and mapping needs for earthquake risk assessment. We discuss this in the context of development of a Global Exposure Database for the Global Earthquake Model (GED4GEM), which requires compilation of a multi-scale inventory of assets at risk, for example, buildings, populations, and economic exposure. After defining the relevant sp
Authors
F. Dell’Acqua, P. Gamba, K. Jaiswal
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
W phase source inversion for moderate to large earthquakes (1990-2010)
Rapid characterization of the earthquake source and of its effects is a growing field of interest. Until recently, it still took several hours to determine the first-order attributes of a great earthquake (e.g. Mw≥ 7.5), even in a well-instrumented region. The main limiting factors were data saturation, the interference of different phases and the time duration and spatial extent of the source rup
Authors
Zacharie Duputel, Luis Rivera, Hiroo Kanamori, Gavin P. Hayes
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
A global earthquake discrimination scheme to optimize ground-motion prediction equation selection
We present a new automatic earthquake discrimination procedure to determine in near-real time the tectonic regime and seismotectonic domain of an earthquake, its most likely source type, and the corresponding ground-motion prediction equation (GMPE) class to be used in the U.S. Geological Survey (USGS) Global ShakeMap system. This method makes use of the Flinn–Engdahl regionalization scheme, seism
Authors
Daniel Garcia, David J. Wald, Michael Hearne
Seismic hazard assessment for Guam and the Northern Mariana Islands
We present the results of a new probabilistic seismic hazard assessment for Guam and the Northern Mariana Islands. The Mariana island arc has formed in response to northwestward subduction of the Pacific plate beneath the Philippine Sea plate, and this process controls seismic activity in the region. Historical seismicity, the Mariana megathrust, and two crustal faults on Guam were modeled as seis
Authors
Charles S. Mueller, Kathleen M. Haller, Nicholas Luco, Mark D. Petersen, Arthur D. Frankel
LiDAR and field observations of slip distribution for the most recent surface ruptures along the central San Jacinto fault
We measured offsets on tectonically displaced geomorphic features along 80 km of the Clark strand of the San Jacinto fault (SJF) to estimate slip‐per‐event for the past several surface ruptures. We identify 168 offset features from which we make over 490 measurements using B4 light detection and ranging (LiDAR) imagery and field observations. Our results suggest that LiDAR technology is an exempla
Authors
J.B. Salisbury, T.K. Rockwell, T.J. Middleton, Kenneth W. Hudnut