Publications
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Shallow degassing events as a trigger for very-long-period seismicity at Kilauea Volcano, Hawaii
The first eruptive activity at Kīlauea Volcano’s summit in 25 years began in March 2008 with the opening of a 35-m-wide vent in Halema‘uma‘u crater. The new activity has produced prominent very-long-period (VLP) signals corresponding with two new behaviors: episodic tremor bursts and small explosive events, both of which represent degassing events from the top of the lava column. Previous work has
Authors
Matthew R. Patrick, David C. Wilson, David Fee, Tim R. Orr, Don Swanson
Isostatic gravity map of the Point Sur 30' x 60' quadrangle and adjacent areas, California
This isostatic residual gravity map is part of a regional effort to investigate the tectonics and water resources of the central Coast Range. This map serves as a basis for modeling the shape of basins and for determining the location and geometry of faults in the area. Local spatial variations in the Earth's gravity field (after removing variations caused by instrument drift, earth-tides, latitud
Authors
J. T. Watt, R. L. Morin, V. E. Langenheim
Flow speed estimated by inverse modeling of sandy sediment deposited by the 29 September 2009 tsunami near Satitoa, east Upolu, Samoa
Sandy deposits from the 29 September 2009 tsunami on the east coast of Upolu, Samoa were investigated to document their characteristics and used to apply an inverse sediment transport model to estimate tsunami flow speed. Sandy deposits 6 to 15 cm thick formed from ~ 25 to ~ 250 m inland. Sedimentary layers in the deposits, that are defined by vertical grain size variation and contacts, are interp
Authors
Bruce E. Jaffe, Mark Buckley, Bruce M. Richmond, Luke Strotz, Samuel Etienne, Kate Clark, Steve Watt, Guy R. Gelfenbaum, James Goff
Publications of the Volcano Hazards Program 2009
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by congressional appropriation. Investigations are carried out in the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute, University of Hawaii Manoa and Hilo, University of Utah,
Authors
Manuel Nathenson
The 1996-2009 borehole dilatometer installations, operation, and maintenance at sites in Long Valley Caldera, CA
High seismicity levels with accelerating uplift (under the resurgent dome) in Long Valley caldera in the eastern Sierra Nevada from 1989 to 1997, triggered upgrades to dilational strainmeters and other instrumentation installed in the early 1980's following a series of magnitude 6 earthquakes. This included two additional high-resolution borehole strainmeters and replacement of the failed strainme
Authors
Glenn Myren, Malcolm Johnston, Robert Mueller
Report on the 2010 Chilean earthquake and tsunami response
In July 2010, in an effort to reduce future catastrophic natural disaster losses for California, the American Red Cross coordinated and sent a delegation of 20 multidisciplinary experts on earthquake response and recovery to Chile. The primary goal was to understand how the Chilean society and relevant organizations responded to the magnitude 8.8 Maule earthquake that struck the region on February
Authors
PQLX: A seismic data quality control system description, applications, and users manual
We present a detailed description and users manual for a new tool to evaluate seismic station performance and characteristics by providing quick and easy transitions between visualizations of the frequency and time domains. The software is based on the probability density functions (PDF) of power spectral densities (PSD) (McNamara and Buland, 2004) and builds on the original development of the PDF
Authors
Daniel E. McNamara, Richard I. Boaz
Introduction: Special issue on earthquake ground-motion selection and modification for nonlinear dynamic analysis of structures
No abstract available.
Authors
Erol Kalkan, Nicolas Luco
Gas hydrate characterization and grain-scale imaging of recovered cores from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope
Using cryogenic scanning electron microscopy (CSEM), powder X-ray diffraction, and gas chromatography methods, we investigated the physical states, grain characteristics, gas composition, and methane isotopic composition of two gas-hydrate-bearing sections of core recovered from the BPXA–DOE–USGS Mount Elbert Gas Hydrate Stratigraphic Test Well situated on the Alaska North Slope. The well was cont
Authors
Laura A. Stern, T.D. Lorenson, John C. Pinkston
Epistemic uncertainty in California-wide synthetic seismicity simulations
The generation of seismicity catalogs on synthetic fault networks holds the promise of providing key inputs into probabilistic seismic-hazard analysis, for example, the coefficient of variation, mean recurrence time as a function of magnitude, the probability of fault-to-fault ruptures, and conditional probabilities for foreshock–mainshock triggering. I employ a seismicity simulator that includes
Authors
Fred F. Pollitz
Low strength of deep San Andreas fault gouge from SAFOD core
The San Andreas fault accommodates 28–34 mm yr−1 of right lateral motion of the Pacific crustal plate northwestward past the North American plate. In California, the fault is composed of two distinct locked segments that have produced great earthquakes in historical times, separated by a 150-km-long creeping zone. The San Andreas Fault Observatory at Depth (SAFOD) is a scientific borehole located
Authors
David A. Lockner, Carolyn A. Morrow, Diane E. Moore, Stephen H. Hickman
Field reconnaissance report of landslides triggered by the January 12, 2010, Haiti earthquake
No abstract available.
Authors
Randall W. Jibson, Edwin L. Harp