Publications
Filter Total Items: 2057
Strain accumulation north of Los Angeles, California, as a function of time, 1977–1992 Strain accumulation north of Los Angeles, California, as a function of time, 1977–1992
No significant change in the rate of strain accumulation in a 40×120 km trilateration network spanning the San Gabriel mountains was observed from 1977.5 to 1991.8 despite an apparent increase in seismicity (ML > 4.5) beginning in late 1987 in the northern Los Angeles basin immediately to the south. The observed deformation (0.13±0.01 µstrain/yr right‐lateral shear across a vertical...
Authors
James C. Savage, Michael Lisowski
Evidence for near-frictionless faulting in the 1989 (M 6.9) Loma Prieta, California, earthquake and its aftershocks: Comment and Reply Evidence for near-frictionless faulting in the 1989 (M 6.9) Loma Prieta, California, earthquake and its aftershocks: Comment and Reply
No abstract available.
Authors
James C. Savage, Mark D. Zoback, G. Beroza
Evolution of the Precambrian lithosphere: Seismological and geochemical constraints Evolution of the Precambrian lithosphere: Seismological and geochemical constraints
Several recent models of crustal evolution are based on the belief that the thickness of the continental crust is proportional to its age, with ancient crust being the thickest. A worldwide review of seismic structure contradicts this belief and falsifies these models, at least for the Archean. Proterozoic crust has a thickness of 40–55 km and a substantial high‐velocity (>7 km/s) layer...
Authors
R. Durrheim, Walter D. Mooney
Crustal velocity structure of the northern Yukon-Tanana upland, central Alaska: Results from TACT refraction/wide-angle reflection data Crustal velocity structure of the northern Yukon-Tanana upland, central Alaska: Results from TACT refraction/wide-angle reflection data
The Fairbanks North seismic refraction/ wide-angle reflection profile, collected by the U.S. Geological Survey Trans-Alaska Crustal Transect (TACT) project in 1987, crosses the complex region between the Yukon-Tanana and Ruby terranes in interior Alaska. This region is occupied by numerous small terranes elongated in a northeast-southwest direction. These seismic data reveal a crustal...
Authors
Bruce C. Beaudoin, Gary S. Fuis, William J. Lutter, Walter D. Mooney, Thomas E. Moore
Crustal structure and composition of the southern Foothills Metamorphic Belt, Sierra Nevada, California, from seismic data Crustal structure and composition of the southern Foothills Metamorphic Belt, Sierra Nevada, California, from seismic data
The Foothills Metamorphic Belt is an accreted terrane consisting of Paleozoic and Mesozoic metamorphic rocks that separates the Great Valley from the Sierra Nevada batholith in northern and central California. Until recently, the only available geophysical data for this area were reconnaissance refraction surveys, and gravity and magnetic data. New insights into the structure of the deep...
Authors
Kate Miller, Walter D. Mooney
Early warning system for aftershocks Early warning system for aftershocks
A prototype early warning system to provide San Francisco and Oakland, California a few tens-of-seconds warning of incoming strong ground shaking from already-occurred M ≧ 3.7 aftershocks of the magnitude 7.1 17 October 1989 Loma Prieta earthquake was operational on 28 October 1989. The prototype system consisted of four components: ground motion sensors in the epicentral area, a central...
Authors
W. H. Bakun, F.G. Fischer, E.G. Jensen, J. VanSchaack
The Loma Prieta, California, Earthquake of October 17, 1989: Strong ground motion The Loma Prieta, California, Earthquake of October 17, 1989: Strong ground motion
Strong ground motion generated by the Loma Prieta, Calif., earthquake (MS~7.1) of October 17, 1989, resulted in at least 63 deaths, more than 3,757 injuries, and damage estimated to exceed $5.9 billion. Strong ground motion severely damaged critical lifelines (freeway overpasses, bridges, and pipelines), caused severe damage to poorly constructed buildings, and induced a significant...
Authors
Roger D. Borcherdt, A. Gerald Brady, A.F. Shakal, V.F. Cormier, Wei-Jou Su, Jeffry L. Stevens, Steven M. Day, John E. Vidale, Ornella Bonamassa, Paul G. Somerville, Nancy F. Smith, Robert Graves, Gary Glassmoyer, Kyle Rollins, Michael D. Mchood, Roman D. Hryciw, Matthew Homolka, Scott E. Shewbridge, Harvey Carlisle, Nicholas Sitar, Rodrigo Salgado, Pedro de Alba, J. Benoit, Daniel G. Pass, John Carter, T. Leslie Youd, E. H. Field, Susan E. Hough, K.H. Jacob, Paul A. Friberg, Arthur D. Frankel, R. Busby, Robert A. Williams, Edward Cranswick, Kenneth W. King, Grant T. Lindley, Ralph J. Archuleta, Janice M. Murphy, Steven G. Wesnousky
The Loma Prieta, California, Earthquake of October 17, 1989 — Hydrologic disturbances The Loma Prieta, California, Earthquake of October 17, 1989 — Hydrologic disturbances
Seismic events have long been known to cause changes in the level of oceans, streams, lakes, and the water table. The great San Francisco earthquake of 1906 induced significant hydrologic changes that were qualitatively similar to those changes observed for the Loma Prieta earthquake. What is different is that the hydrologic data sets collected from the Loma Prieta event have enough...
Crustal architecture of the Cascadia Forearc Crustal architecture of the Cascadia Forearc
Seismic profiling data indicate that the thickness of an accreted oceanic terrane of Paleocene and early Eocene age, which forms the basement of much of the forearc beneath western Oregon and Washington, varies by approximately a factor of 4 along the strike of the Cascadia subduction zone. Beneath the Oregon Coast Range, the accreted terrane is 25 to 35 kilometers thick, whereas...
Authors
A.M. Trehu, I. Asudeh, Thomas M. Brocher, James H. Luetgert, Walter D. Mooney, J.L. Nabelek, Y. Nakamura
Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Loss estimation and procedures Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Loss estimation and procedures
This Professional Paper includes a collection of papers on subjects ranging from evaluation of building safety, to human injuries, to correlation of ground deformation with building damage. What these papers share is a common goal to improve the tools available to the research community to measure the nature, extent, and causes of damage and losses due to earthquakes. These measurement...
The East African rift system in the light of KRISP 90 The East African rift system in the light of KRISP 90
On the basis of a test experiment in 1985 (KRISP 85) an integrated seismic-refraction/teleseismic survey (KRISP 90) was undertaken to study the deep structure beneath the Kenya rift down to depths of 100–150 km. This paper summarizes the highlights of KRISP 90 as reported in this volume and discusses their broad implications as well as the structure of the Kenya rift in the general...
Authors
Gordon R. Keller, C. Prodehl, J. Mechie, K. Fuchs, M.A. Khan, Peter K.H. Maguire, Walter D. Mooney, U. Achauer, P.M. Davis, R.P. Meyer, L.W. Braile, I.O. Nyambok, G. A. Thompson
Probability of one or more M ≥7 earthquakes in southern California in 30 years Probability of one or more M ≥7 earthquakes in southern California in 30 years
Eight earthquakes of magnitude greater than or equal to seven have occurred in southern California in the past 200 years. If one assumes that such events are the product of a Poisson process, the probability of one or more earthquakes of magnitude seven or larger in southern California within any 30 year interval is 67% ± 23% (95% confidence interval). Because five of the eight M ≥ 7...
Authors
James C. Savage