Publications
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A numerical study of some potential sources of error in side-by-side seismometer evaluations
This report presents the results of a series of computer simulations of potential errors in test data, which might be obtained when conducting side-by-side comparisons of seismometers. These results can be used as guides in estimating potential sources and magnitudes of errors one might expect when analyzing real test data. First, the derivation of a direct method for calculating the noise levels
Authors
L. Gary Holcomb
The San Andreas Fault System, California
Maps of northern and southern California printed on flyleaf inside front cover and on adjacent pages show faults that have had displacement within the past 2 million years. Those that have had displacement within historical time are shown in red. Bands of red tint emphasize zones of historical displacement; bands of orange tint emphasize major faults that have had Quaternary displacement before hi
By
Energy and Minerals Mission Area, Natural Hazards Mission Area, Earthquake Hazards Program, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Earthquake Science Center, Geologic Hazards Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Source parameters and effects of bandwidth and local geology on high- frequency ground motions observed for aftershocks of the northeastern Ohio earthquake of 31 January 1986
A 10-station array (GEOS) yielded recordings of exceptional bandwidth (400 sps) and resolution (up to 96 dB) for the aftershocks of the moderate (mb ≈ 4.9) earthquake that occurred on 31 January 1986 near Painesville, Ohio. Nine aftershocks were recorded with seismic moments ranging between 9 × 1016 and 3 × 1019 dyne-cm (Mw: 0.6 to 2.3). The two largest aftershocks (depth 5.3, 5.6 km; oblique righ
Authors
G. Glassmoyer, R. D. Borcherdt
The eruption of Redoubt Volcano, Alaska, December 14, 1989-August 31, 1990
No abstract available.
Authors
Thomas J. Casadevall, Bernard A. Chouet, John N. Davies, Steven A. Estes, Cynthia A. Gardner, Richard P. Hoblitt, John C. Lahr, Richard G. Lahusen, Jon J. Major, Robert G. McGimsey, Thomas P. Miller, Thomas L. Murray, Christina A. Neal, Christopher J. Nye, Robert A. Page, Thomas C. Pierson, John Power, Christopher D. Stephens, Richard B. Waitt
Seismic-wave attenuation associated with crustal faults in the New Madrid seismic zone
The attenuation of upper crustal seismic waves that are refracted with a velocity of about 6 kilometers per second varies greatly among profiles in the area of the New Madrid seismic zone in the central Mississippi Valley. The waves that have the strongest attenuation pass through the seismic trend along the axis of the Reelfoot rift in the area of the Blytheville arch. Defocusing of the waves in
Authors
R. M. Hamilton, Walter D. Mooney
Deep crustal structure of the Cascade Range and surrounding regions from seismic refraction and magnetotelluric data
Several regional seismic refraction and magnetotelluric (MT) profiles have been completed across the Cascade Range and surrounding geologic provinces in California, Oregon, and Washington. Analysis of three MT and two seismic refraction profiles in Oregon and a coincident MT and refraction profile in northern California show a high degree of correlation between resistivity and velocity models. The
Authors
William D. Stanley, Walter D. Mooney, Gary S. Fuis
Crustal structure of the northwestern Basin and Range Province from the 1986 Program for Array Seismic Studies of the Continental Lithosphere Seismic Experiment
A portion of northwestern Nevada was imaged to determine the crustal structure and to assess reported differences between refraction versus reflection determinations of Moho depth and how the crustal composition and structure has been influenced by volcanic and extension mechanisms. Interpretation of the refraction/wide-angle reflection data suggests that the crust is fairly uniform in thickness a
Authors
Harley M. Benz, R. B. Smith, Walter D. Mooney
Crustal structure of the Chugach Mountains, southern Alaska: A study of peg‐leg multiples from a low‐velocity zone
A seismic refraction profile recorded along the geologic strike of the Chugach Mountains in southern Alaska shows three upper crustal high‐velocity layers (6.9, 7.2, and 7.6 km/s) and a unique pattern of strongly focussed echelon arrivals to a distance of 225 km. The group velocity of the ensemble of echelon arrivals is 6.4 km/s. Modeling of this profile with the reflectivity method reveals that t
Authors
Ernst Flueh, Walter D. Mooney, Gary S. Fuis, Elizabeth L. Ambos
An exact anelastic model for the free-surface reflection of P and S-I waves
Exact anelastic solutions incorporating inhomogeneous waves are used to model numerically S-I and P waves incident on the free surface of a low-loss anelastic half-space. Anelastic free-surface reflection coefficients are computed for the volumetric strain and displacement components of inhomogeneous wave fields. For the problem of an incident homogeneous S-I wave in Pierre shale, the largest stra
Authors
Roger D. Borcherdt, G. Glassmoyer
Geophysical framework of the continental United States: Progress, problems, and opportunities for research
Significant progress has been made over the past five decades in determining the geophysical framework of the continental United States. Highlights include detailed maps of gravity and aeromagnetic anomalies, heat flow, crustal thickness, seismicity, state of stress, and paleomagnetic pole positions. Important tectonic insights have come from earthquake studies, and from knowledge of lithospheric
Authors
Walter D. Mooney, L. C. Pakiser
Regional crustal structure and tectonics of the Pacific Coastal States: California, Oregon, and Washington
The Pacific Coastal States form a complex geologic environment in which the crust and lithosphere have been continuously reworked. We divide the region tectonically into the southern transform regime of the San Andreas fault and the northern subduction regime, and summarize the geophysical framework with contour maps of crustal thickness, lithospheric and seismicity cross sections, and results fro
Authors
Walter D. Mooney, Craig S. Weaver