Publications
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A generalization of the double-corner-frequency source spectral model and its use in the SCEC BBP validation exercise
The stochastic method of simulating ground motions requires the specification of the shape and scaling with magnitude of the source spectrum. The spectral models commonly used are either single-corner-frequency or double-corner-frequency models, but the latter have no flexibility to vary the high-frequency spectral levels for a specified seismic moment. Two generalized double-corner-frequency ω2
Authors
David M. Boore, Carola Di Alessandro, Norman A. Abrahamson
Stochastic ground motion simulation
Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensi
Authors
Sanaz Rezaeian, Sun Xiaodan
Frequency-dependent effects of rupture for the 2004 Parkfield mainshock, results from UPSAR
The frequency-dependent effects of rupture propagation of the Parkfield, California earthquake (Sept. 28, 2004, M6) to the northwest along the San Andreas fault can be seen in acceleration records at UPSAR (USGS Parkfield Seismic Array) in at least two ways. First, we can see the effects of directivity in the acceleration traces at UPSAR, which is about 11.5 km from the epicenter. Directivity or t
Authors
Jon B. Fletcher
Seismic structure of the central US crust and upper mantle: Uniqueness of the Reelfoot Rift
Using seismic surface waves recorded with Earthscope's Transportable Array, we apply surface wave imaging to determine 3D seismic velocity in the crust and uppermost mantle. Our images span several Proterozoic and early Cambrian rift zones (Mid-Continent Rift, Rough Creek Graben—Rome trough, Birmingham trough, Southern Oklahoma Aulacogen, and Reelfoot Rift). While ancient rifts are generally assoc
Authors
Fred Pollitz, Walter D. Mooney
Progress toward a safer future since the 1989 Loma Prieta earthquake
The 1989 Loma Prieta earthquake interrupted several decades of seismic tranquility in the San Francisco Bay Area. It caused damage throughout the region and was a wakeup call to prepare for potentially even more damaging future quakes. Since 1989, the work of the U.S. Geological Survey and many other organizations has improved the understanding of the seismic threat in the Bay Area, promoted aware
Authors
Thomas M. Brocher, Robert A. Page, Peter H. Stauffer, James W. Hendley
Operational earthquake forecasting can enhance earthquake preparedness
We cannot yet predict large earthquakes in the short term with much reliability and skill, but the strong clustering exhibited in seismic sequences tells us that earthquake probabilities are not constant in time; they generally rise and fall over periods of days to years in correlation with nearby seismic activity. Operational earthquake forecasting (OEF) is the dissemination of authoritative info
Authors
T.H. Jordan, W. Marzocchi, A.J. Michael, M.C. Gerstenberger
ShakeAlert—An earthquake early warning system for the United States west coast
Earthquake early warning systems use earthquake science and the technology of monitoring systems to alert devices and people when shaking waves generated by an earthquake are expected to arrive at their location. The seconds to minutes of advance warning can allow people and systems to take actions to protect life and property from destructive shaking. The U.S. Geological Survey (USGS), in collabo
Authors
Erin R. Burkett, Douglas D. Given, Lucile M. Jones
Advancing geodesy in the U.S. Midcontinent: workshop report
The workshop on “Advancing Geodesy in the U.S. Midcontinent” was held from October 31 to November 1, 2012, at Northwestern University in Evanston, Illinois. The workshop included 28 participants from academia, government, and private-sector organizations that are involved in research on geodesy and earthquake hazards in the seismically active areas of the U.S. midcontinent (the region of relativel
Authors
Michael W. Hamburger, Oliver S. Boyd, Eric Calais, Nancy E. King, Seth A. Stein
Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake
The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile which had not r
Authors
Gavin P. Hayes, Matthew W. Herman, William D. Barnhart, Kevin P. Furlong, Sebástian Riquelme, Harley M. Benz, Eric Bergman, Sergio Barrientos, Paul S. Earle, Sergey Samsonov
Grain-scale imaging and compositional characterization of cryo-preserved India NGHP 01 gas-hydrate-bearing cores
We report on grain-scale characteristics and gas analyses of gas-hydrate-bearing samples retrieved by NGHP Expedition 01 as part of a large-scale effort to study gas hydrate occurrences off the eastern-Indian Peninsula and along the Andaman convergent margin. Using cryogenic scanning electron microscopy, X-ray spectroscopy, and gas chromatography, we investigated gas hydrate grain morphology and d
Authors
Laura A. Stern, T.D. Lorenson
Seismicity, faulting, and structure of the Koyna-Warna seismic region, Western India from local earthquake tomography and hypocenter locations
Although seismicity near Koyna Reservoir (India) has persisted for ~50 years and includes the largest induced earthquake (M 6.3) reported worldwide, the seismotectonic framework of the area is not well understood. We recorded ~1800 earthquakes from 6 January 2010 to 28 May 2010 and located a subset of 343 of the highest-quality earthquakes using the tomoDD code of Zhang and Thurber (2003) to bette
Authors
Madan M. Dixit, Sanjay Kumar, Rufus D. Catchings, K. Suman, Dipankar Sarkar, M.K. Sen
Bayesian historical earthquake relocation: an example from the 1909 Taipei earthquake
Locating earthquakes from the beginning of the modern instrumental period is complicated by the fact that there are few good-quality seismograms and what traveltimes do exist may be corrupted by both large phase-pick errors and clock errors. Here, we outline a Bayesian approach to simultaneous inference of not only the hypocentre location but also the clock errors at each station and the origin ti
Authors
Sarah E. Minson, William H.K. Lee