Publications
Educational Publications
Educational Publications
Selected publications about earthquakes In plain language.
Filter Total Items: 2819
Site-response maps for the Los Angeles region based on earthquake ground motions Site-response maps for the Los Angeles region based on earthquake ground motions
Ground-motion records from aftershocks of the 1994 Northridge earthquake and main-shock records from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, and 1994 Northridge earthquakes are used to estimate site response in the urban Los Angeles, California, area. Two frequency bands are considered, 0.5-1.5 Hz and 2.0-6.0 Hz. Instrument characteristics prevented going to...
Authors
Stephen H. Hartzell, Stephen C. Harmsen, Arthur D. Frankel, David L. Carver, Edward Cranswick, Mark E. Meremonte, John A. Michael
The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics The Loma Prieta, California, Earthquake of October 17, 1989: Main shock characteristics
The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036º N., long 121.883º W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip occurred on a dipping fault surface about 35...
Authors
Paul A. Spudich, Gregory C. Beroza, George Choy, John Boatwright, Stephen H. Hartzell, Gordon L. Stewart, Carlos Mendoza, Stephen Horton, John G. Anderson, Andres J. Mendez, Hiroo Kanamori, Kenji Satake, Michael Lisowski, Mark Hunter Murray, Jerry L. Svarc, Grant Marshall, Ross S. Stein, Karen McNally, Gerald W. Simila, Judy G. Brown, J.L. Nabelek, Ze’ev Reches, Mark D. Zoback, Jamison Steidl, Ralph J. Archuleta, Aaron A. Velasco, Thorne Lay, Jiajun Zhang, David J. Wald, Donald V. Helmberger, Thomas H. Heaton, Chesley R. Williams, Paul Segall, Francis T. Wu, Mingdong Wu, J.W. Rudnicki
Seismic anisotropy of the crystalline crust: What does it tell us? Seismic anisotropy of the crystalline crust: What does it tell us?
The study of the directional dependence of seismic velocities (seismic anisotropy) promises more refined insight into mineral composition and physical properties of the crystalline crust than conventional deep seismic refraction or reflection profiles providing average values of P-and S-wave velocities. The alignment of specific minerals by ductile rock deformation, for instance, causes...
Authors
Wolfgang Rabbel, Walter D. Mooney
Origin of high mountains in the continents: The Southern Sierra Nevada Origin of high mountains in the continents: The Southern Sierra Nevada
Active and passive seismic experiments show that the southern Sierra, despite standing 1.8 to 2.8 kilometers above its surroundings, is underlain by crust of similar seismic thickness, about 30 to 40 kilometers. Thermobarometry of xenolith suites and magnetotelluric profiles indicate that the upper mantle is eclogitic to depths of 60 kilometers beneath the western and central parts of...
Authors
B. Wernicke, R. Clayton, Mihai N. Ducea, C.H. Jones, S. Park, S. Ruppert, J. Saleeby, J.K. Snow, L. Squires, M. Fliedner, G. Jiracek, Rebecca Hylton Keller, S. Klemperer, J. Luetgert, P. Malin, K. Miller, Walter D. Mooney, H. Oliver, R. Phinney
Damage and restoration of geodetic infrastructure caused by the 1994 Northridge, California, earthquake Damage and restoration of geodetic infrastructure caused by the 1994 Northridge, California, earthquake
We seek to restore the integrity of the geodetic network in the San Fernando, Simi, Santa Clarita Valleys and in the northern Los Angeles Basin by remeasurement of the network and identification of BMs which experienced non-tectonic displacements associated with the Northridge earthquake. We then use the observed displacement of BMs in the network to portray or predict the permanent...
Authors
Kathleen M. Hodgkinson, Ross S. Stein, Kenneth W. Hudnut, Jay Satalich, John H. Richards
Quake Forecasting- An Emerging Capability Quake Forecasting- An Emerging Capability
No abstract available.
Authors
Andrew Michael, Paul Reasenberg, Peter H. Stauffer, James W. Hendley
Transition from slab to slabless: Results from the 1993 Mendocino triple junction seismic experiment Transition from slab to slabless: Results from the 1993 Mendocino triple junction seismic experiment
Three seismic refraction-reflection profiles, part of the Mendocino triple junction seismic experiment, allow us to compare and contrast crust and upper mantle of the North American margin before and after it is modified by passage of the Mendocino triple junction. Upper crustal velocity models reveal an asymmetric Great Valley basin overlying Sierran or ophiolitic rocks at the latitude...
Authors
B. C. Beaudoin, N. J. Godfrey, S.L. Klemperer, C. Lendl, A.M. Trehu, T.J. Henstock, A. Levander, J.E. Holl, A.S. Meltzer, James H. Luetgert, Walter D. Mooney
Strain accumulation across the central Nevada seismic zone, 1973–1994 Strain accumulation across the central Nevada seismic zone, 1973–1994
Five trilateration networks extending for 280 km along the central Nevada seismic zone (1915 Pleasant Valley, M = 7.3; 1954 Dixie Valley, M = 6.8; 1954 Stillwater, M = 6.8; 1954 Rainbow Mountain, M = 6.6; 1954 Fairview Peak, M = 7.1; and 1932 Cedar Mountain, M = 7.2) have been surveyed 6 times since 1973 to determine deformation along the zone. Within the precision of measurement the...
Authors
James C. Savage, Michael Lisowski, W.K. Gross
Changes in long‐term extension rates associated with the Morgan Hill and Loma Prieta earthquakes in California Changes in long‐term extension rates associated with the Morgan Hill and Loma Prieta earthquakes in California
Frequent measurements since mid‐1981 of the distances from a geodetic monument located about 100 km south‐southeast of San Francisco to three monuments 30 to 40 km distant provide an unusually complete record of the deformation before and after two nearby earthquakes, the 1984 Morgan Hill (ML = 6.2) and 1989 Loma Prieta (Ms = 7.1) earthquakes. Except possibly for the first few months...
Authors
James C. Savage, Michael Lisowski
Strain accumulation in Owens Valley, California, 1974 to 1988 Strain accumulation in Owens Valley, California, 1974 to 1988
Strain accumulation observed over the 1974 to 1988 interval in a 25 by 100 km aperture trilateration network spanning Owens Valley is adequately described by a strain rate that is uniform in space and time. The tensor strain-rate components referred to a coordinate system with the 2 axis directed N18°W (parallel to the trend of the valley) and the 1 axis N72°E are ∈˙11′ = 0.042 ± 0.014...
Authors
James C. Savage, Michael Lisowski
Geodetic monitoring of the southern San Andreas Fault, California, 1980-1991 Geodetic monitoring of the southern San Andreas Fault, California, 1980-1991
Five geodetic arrays (10 to 40 km aperture) located along the San Andreas fault have been surveyed frequently (several times in most years) over the 1980–1991 interval to detect possible fluctuations in the deformation rate. In each survey of an array the distances between the same four to seven pairs of geodetic monuments were measured. The distances measured (with corresponding...
Authors
James C. Savage, Michael Lisowski
Interseismic uplift at the Nankai subduction zone, southwest Japan, 1951–1990 Interseismic uplift at the Nankai subduction zone, southwest Japan, 1951–1990
Uplift as a function of time from 1951 through 1990 has been deduced from annual mean sea level measured at 15 tide gages along the Nankai subduction zone, southwest Japan. The recurrence interval for rupture of the Nankai subduction zone is about 100 years, and the most recent rupture was in late 1946. Thus the 1951–1990 uplift record covers most of the first half of the earthquake...
Authors
James C. Savage