The 2014 Working Group on California Earthquake Probabilities (WGCEP 2014) presents time-dependent earthquake probabilities for the third Uniform California Earthquake Rupture Forecast (UCERF3). Building on the UCERF3 time-independent model published previously, renewal models are utilized to represent elastic-rebound-implied probabilities. A new methodology has been developed that solves applicability issues in...
This article summarizes the geotechnical effects of the 25 April 2015 M 7.8 Gorkha, Nepal, earthquake and aftershocks, as documented by a reconnaissance team that undertook a broad engineering and scientific assessment of the damage and collected perishable data for future analysis. Brief descriptions are provided of ground shaking, surface...
The Queen Charlotte fault (QCF) is a dextral transform system located offshore of southeastern Alaska and western Canada, accommodating ∼4.4 cm/yr of relative motion between the Pacific and North American plates. Oblique convergence along the fault increases southward, and how this convergence is accommodated is still debated. Using seismic reflection...
Several approaches to interpreting the Cascadia paleoseismic record are
used to derive relationships between fault area, slip, and moment and to compare the
results with the scaling relationships determined by Somerville et al. (2015) for recent
subduction-zone events. In two models (CA12a and CA12b), taken from Goldfinger
et al. (2012),...
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–911, June 2016, doi: 10.1785/0120150272
different tectonic settings (e.g., Kanamori and Anderson
Maximum earthquake magnitude (m[subscript x]) is a critical parameter in seismic
hazard and risk analysis. However, some recent large earthquakes have shown that
most of the existing methods for estimating m[subscript x] are inadequate. Moreover, m[subscript x] itself is ill-defined because its meaning largely depends on the context, and it...
Since 2003, 39 small earthquakes have been detected offshore central Oregon in the nominally locked part of the Cascadia subduction zone, where very little seis- mic activity has been recorded in spite of a paleo-seismic record of great subduction events. Although the regional earthquake bulletin reports depths of 29 and...
Here we use SKS shear wave splitting observations from ocean-bottom seismometer data to infer patterns of mantle deformation beneath the Juan de Fuca plate and its adjoining boundaries. Our results indicate that the asthenosphere beneath the Juan de Fuca plate responds largely to absolute plate motion with an anisotropic layer...
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doi:10.1785/0220150017. 244
Sumy, D. F., Lodewyk, J. A., Woodward, R. L., & Evers, B., 2015, Ocean
Mid-ocean ridge volcanism and extensional faulting are the fundamental processes that lead to the creation and rifting of oceanic crust, yet these events go largely undetected in the deep ocean. Currently, the only means available to observe seafloor-spreading events in real time is via the remote detection of the seismicity...
Analysis of continuous seismic data recorded by a dense passive seismological network (Hi‐CLIMB) installed across the Himalayas reveals strong spatial and temporal variations in the ambient seismic energy produced at high frequencies (>1 Hz). From June to September 2003, the high‐frequency seismic noise is observed to increase up to 20...
The 2014 Working Group on California Earthquake Probabilities
(WGCEP14) present the time-independent component of the Uniform California
Earthquake Rupture Forecast, Version 3 (UCERF3), which provides authoritative
estimates of the magnitude, location, and time-averaged frequency of potentially
damaging earthquakes in California. The primary achievements have been to relax
fault segmentation and...