Publications
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The 1906 San Francisco earthquake a century later: Introduction to the special section
The great 1906 San Francisco earthquake is perhaps the landmark event in the history of earthquake science. It began with a foreshock at 5:12 a.m. local time in the morning of 18 April 1906. Some 30 sec later, the main event initiated on the San Andreas fault, just off the San Francisco coast (Lawson, 1908). Within 90 sec, nearly 480 km of the San Andreas fault ruptured (see Fig. 1), extending sou
Authors
Brad T. Aagaard, Gregory C. Beroza
Maximum spectral demands in the near-fault region
The Next Generation Attenuation (NGA) relationships for shallow crustal earthquakes in the western United States predict a rotated geometric mean of horizontal spectral demand, termed GMRotI50, and not maximum spectral demand. Differences between strike-normal, strike-parallel, geometric-mean, and maximum spectral demands in the near-fault region are investigated using 147 pairs of records selecte
Authors
Yin-Nan Huang, Andrew S. Whittaker, Nicolas Luco
Shear wave structure of Umbria and Marche, Italy, strong motion seismometer sites Affected by the 1997-98 Umbria-Marche, Italy, earthquake sequence
A long sequence of earthquakes, eight with magnitudes between 5 and 6, struck the Umbria and Marche regions of central Italy between September 26, 1997 and July 1998. The earthquake swarm caused severe structural damage, particularly to masonry buildings, and resulted in the loss of twelve lives and about 150 injuries. The source of the events was a single seismogenic structure that consists of se
Authors
Robert Kayen, Giuseppe Scasserra, Jonathan P. Stewart, Giuseppe Lanzo
A slab fragment wedged under Tokyo and its tectonic and seismic implications
The Philippine Sea and Pacific plate slabs both subduct beneath Tokyo, and so their configuration and seismic potential have been subject to intensive study. Previous work suggests that the Philippine Sea slab extends up to 100 km northwest of Tokyo and subducts to a depth of 90 km beneath the Kanto basin, where it is folded against the underlying Pacific slab. Here we evaluate seismic data in thr
Authors
Shinji Toda, Ross Stein, Stephen H. Kirby, S.B. Bozkurt
Geological and geophysical evaluation of the mechanisms of the great 1899 Yakutat Bay earthquakes
We have used tectonic, geologic, and seismologic observations to reevaluate the mechanisms and seismotectonic significance of the two great (Mw = 8.1 and 8.2) September 1899 Yakutat Bay earthquakes. In their comprehensive study of these earthquakes between 1905 and 1910, Tarr and Martin (1912) showed that these events were accompanied by shoreline changes in Yakutat Bay that ranged from 14.4 m eme
Authors
George Plafker, Wayne R. Thatcher
Toward a time-dependent probabilistic seismic hazard analysis for Alaska
We report on a time-dependent seismic hazard analysis for Alaska and the Aleutians to complement our recently completed time-independent map. Whereas the time-independent map treats all sources as statistically independent, the time-dependent analysis is based on calculations of the conditional probability of occurrence for the next 50 years by using a Brownian Passage Time model for the seismic s
Authors
Oliver S. Boyd, Yuehua Zeng, Charles G. Bufe, Robert L. Wesson, Fred Pollitz, Jeanne L. Hardebeck
Preliminary report on the 29 July 2008 Mw 5.4 Chino Hills, Eastern Los Angeles Basin, California, earthquake sequence
The 29 July 2008 Mw 5.4 Chino Hills earthquake was the largest event to occur within the greater Los Angeles metropolitan region since the Mw 6.7 1994 Northridge earthquake. The earthquake was widely felt in a metropolitan region with a population of more than 10 million people and was recorded by hundreds of broadband and strong-motion instruments. In this report we present preliminary analysis o
Authors
Egill Hauksson, Karen R. Felzer, Doug Given, Michal Giveon, Susan E. Hough, Kate Hutton, Hiroo Kanamori, Volkan Sevilgen, Shengji Wei, Alan K. Yong
Reevaluation of the macroseismic effects of the 1887 Sonora, Mexico earthquake and its magnitude estimation
The Sonora, Mexico, earthquake of 3 May 1887 occurred a few years before the start of the instrumental era in seismology. We revisit all available accounts of the earthquake and assign Modified Mercalli Intensities (MMI), interpreting and analyzing macroseismic information using the best available modern methods. We find that earlier intensity assignments for this important earthquake were unjusti
Authors
Gerardo Suárez, Susan E. Hough
The April 18, 2008 Illinois earthquake: an ANSS monitoring success
The largest-magnitude earthquake in the past 20 years struck near Mt. Carmel in southeastern Illinois on Friday morning, 18 April 2008 at 09:36:59 UTC (04:37 CDT). The Mw 5.2 earthquake was felt over an area that spanned Chicago and Atlanta, with about 40,000 reports submitted to the U.S. Geological Survey (USGS) “Did You Feel It?” system. There were at least six felt aftershocks greater than magn
Authors
Robert B. Herrmann, M. Withers, H. Benz
3D crustal structure and long-period ground motions from a M9.0 megathrust earthquake in the Pacific Northwest region
We have developed a community velocity model for the Pacific Northwest region from northern California to southern Canada and carried out the first 3D simulation of a Mw 9.0 megathrust earthquake rupturing along the Cascadia subduction zone using a parallel supercomputer. A long-period (
Authors
K.B. Olsen, W. J. Stephenson, A. Geisselmeyer
Viscoelastic love-type surface waves
The general theoretical solution for Love-Type surface waves in viscoelastic media provides theoreticalexpressions for the physical characteristics of the waves in elastic as well as anelastic media with arbitraryamounts of intrinsic damping. The general solution yields dispersion and absorption-coefficient curves for the waves as a function of frequency and theamount of intrinsic damping for any
Authors
Roger D. Borcherdt
Development of the U.S. Geological Survey's PAGER system (Prompt Assessment of Global Earthquakes for Response)
The Prompt Assessment of Global Earthquakes for Response (PAGER) System plays a primary alerting role for global earthquake disasters as part of the U.S. Geological Survey’s (USGS) response protocol. We provide an overview of the PAGER system, both of its current capabilities and our ongoing research and development. PAGER monitors the USGS’s near real-time U.S. and global earthquake origins and a
Authors
D. J. Wald, P.S. Earle, T.I. Allen, K. Jaiswal, K. Porter, M. Hearne