Radiation of Rayleigh Wave Energy from Nuclear Explosions and Collapses in Southern Nevada

abstract Surface waves generated by six earthquakes and two nuclear explosions are used to study the attenuation coefficients of the fundamental Rayleigh mode across Eurasia. Rayleigh-wave amplitude data yield average attenuation coefficients at periods between 4 and 50 sec. The data exhibit relatively large standard deviations and in some cases the average attenuation coefficients take on negative values which may be due to regional variations of the attenuative properties of the crust, lateral refraction, multipathing and scattering. A method has been developed to investigate the regional variation in the attenuative properties of the Eurasian crust and its effect on surface-wave amplitude data, employing the evaluated average attenuation coefficients for the fundamental Rayleigh mode. For this investigation, Eurasia is divided into two regions, one considered to be relatively stable, and the other considered to be tectonic in nature. This regionalization shows that the tectonic regions exhibit higher attenuation than the stable regions in the period range below about 20 sec, whereas in the period range above about 20 sec, no clear difference can be observed for the two regions. Although the effects of lateral refraction and multipathing may still significantly affect the observations, the regionalization lowers the standard deviations considerably and eliminates the negative values which were obtained in the unregionalized determinations.

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Amplitude-yield scaling for underground nuclear explosions

Bulletin of the Seismological Society of America ◽

10.1785/bssa0630020477 ◽

1973 ◽

Vol 63 (2) ◽

pp. 477-500 ◽

Cited By ~ 2

Author(s):

D. L. Springer ◽

W. J. Hannon

Keyword(s):

Rayleigh Wave ◽

Statistical Tests ◽

Test Site ◽

Mean Value ◽

P Wave ◽

Source Population ◽

Yield Data ◽

P Waves ◽

Underground Nuclear Explosions ◽

Nuclear Explosions

abstract About 60 sets of seismic amplitude-yield data were examined using standard regression techniques to determine slopes of amplitude-yield scaling relations for explosions in water-saturated tuffs and rhyolites. Both P-wave amplitudes and Rayleigh-wave amplitudes were studied at selected stations located at regional and teleseismic distances. The source population included only those underground nuclear explosions fired near or below the level of the static water table at Pahute Mesa, Nevada Test Site, and covered about three orders of magnitude in yield. Statistical tests applied to the slope parameter (b) indicate that the slopes at regional and teleseismic distances are different. An estimated mean value of b for P-wave amplitude/period (A/T) was slightly greater than 0.6 for regional distances but was almost 1.0 for teleseismic distances. The estimated mean value of b for Rayleigh-wave A/T data was about 1.1. At a given distance the slopes seem to be independent of the yield range considered for both P-waves and Rayleigh-waves.

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Shear Wave Velocity Structure Derived from the Microtremor H/V Rayleigh Wave Energy Rich Part

23rd European Meeting of Environmental and Engineering Geophysics ◽

10.3997/2214-4609.201702064 ◽

2017 ◽

Author(s):

R. Yazdanfar ◽

N. Hafezi Moghaddas

Keyword(s):

Rayleigh Wave ◽

Shear Wave ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Wave Energy ◽

Velocity Structure ◽

Shear Wave Velocity Structure

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Optimizing seismo‐acoustic sonar source array configuration for maximum radiated Rayleigh wave energy

The Journal of the Acoustical Society of America ◽

10.1121/1.4781537 ◽

2006 ◽

Vol 120 (5) ◽

pp. 3368-3368

Author(s):

Anthony N. Johnson ◽

Clyde L. Scandrett ◽

Steven R. Baker

Keyword(s):

Rayleigh Wave ◽

Wave Energy ◽

Array Configuration ◽

Source Array

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Rayleigh wave synthetic seismograms from multi-dimensional simulations of underground explosions

Bulletin of the Seismological Society of America ◽

10.1785/bssa0720010015 ◽

1982 ◽

Vol 72 (1) ◽

pp. 15-28

Author(s):

Thomas C. Bache ◽

Steven M. Day ◽

Henry J. Swanger

Keyword(s):

Free Surface ◽

Rayleigh Wave ◽

Rayleigh Waves ◽

Material Behavior ◽

Earth Model ◽

Far Field ◽

Two Dimensional ◽

Nuclear Explosions ◽

Short Period ◽

Source Wave

abstract A general method is presented for coupling the near-source wave fields, obtained from time-stepping numerical calculations, with analytically formulated methods for continuing the wave field to larger ranges. The source calculation may include a free surface and other material boundaries as well as arbitrary material behavior, as long as it is carried into a region where the material response is linearly elastic. The method, which is based on an elastodynamic representation theorem, is worked out in detail for the Rayleigh wave modes for an axisymmetric source in a plane-layered earth model and is demonstrated by a sample calculation for which the exact solution is known. Two realistic, axisymmetric simulations of nuclear explosions (20 and 150 kt at 1-km depth) are studied to estimate the effect of nonlinear interactions with the free surface on the far-field Rayleigh waves. The importance of these two-dimensional phenomena is quantified by comparing far-field Rayleigh waves computed from these simulations with Rayleigh waves computed from analogous one-dimensional (spherically symmetric) simulations. While the two-dimensional simulations exhibit substantial spallation associated with the free surface, the predicted effect on the Rayleigh wave peak amplitudes is negligible. Two-dimensional effects also alter the waveform very little, apart from some enhancement of very short-period components for the larger explosion.

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