In Part I of this study, we obtained the ray (group) velocity gradients and Hessians with respect to locations, directions anisotropic model parameters, at nodal points along trajectories, considering general (triclinic) media both, quasi-compressional quasi-shear waves. Ray derivatives for higher symmetries were considered particular cases anisotropy. part, II, follow computational workflow pr...

New velocity data in addition to literature data derived from sonic log, seismic, and laboratory measurements are analyzed for elastic silicate rocks. These data demonstrate simple systematic relationships between compressional and shear wave velocities. For water-saturated elastic silicate rocks, shear wave velocity is approximately linearly related to compressional wave velocity and the compr...

[1] Earth’s background vibrations at frequencies below about 0.5 Hz have been attributed to ocean-wave energy coupling into the ground and propagating as surface waves and P-waves (compressional waves deep within the Earth). However, the origin and nature of seismic noise on land at frequencies around 1 Hz has not yet been well studied. Using array beamforming, we analyze the seismic noise fiel...

We examine spectral time series of the transition region line O v 629 A, observed with the Coronal Diagnostic Spectrometer (CDS) on the SoHO spacecraft in July 1997. Both Fourier and wavelet transforms have been applied independently to the analysis of plume oscillations in order to nd the most reliable periods. The wavelet analysis allows us to derive the duration as well as the periods of the...

OF THE DISSERTATION Comparison of Conventional and Bayesian Analysis for the Ultrasonic Characterization of Cancellous Bone by Amber Mae Groopman Doctor of Philosophy in Physics Washington University in St. Louis, 2014 Professor James G. Miller, Chair This dissertation investigates the physics underlying the propagation of ultrasonic waves in cancellous bone. Although quantitative ultrasound ha...

Faults are usually surrounded by damaged zones of lower elastic moduli and seismic wave velocities than their host rocks. If the interface between the damaged rocks and host rocks is sharp enough, earthquakes happening inside the fault zone generate reflected waves and head waves, which can interact with earthquake ruptures and modulate rupture properties such as rupture speed, slip rate, and r...

We aim to identify the physical processes which occur in the magnetic network of the chromosphere and which contribute to its dynamics and heating. Specifically, we study the propagation of transverse (kink) MHD waves which are impulsively excited in flux tubes through footpoint motions. When these waves travel upwards, they get partially converted to longitudinal waves through nonlinear effect...

The permeability of saturated soils has great influence on the velocities and attenuation characteristics fast compressional wave P1, low P2, shear S in soils, respectively. In three different cases, namely zero, finite, infinite permeability, equations theoretical are given based u-w-p equation, According to solutions equations, real coefficients waves redefined, influences loading frequency d...

A theory of compressional and shear wave propagation in consolidated porous media ~rocks! is developed by extending ideas already introduced in connection with unconsolidated marine sediments. The consolidated material is treated as an elastic medium which exhibits a specific form of stress relaxation associated with grain boundaries and microcracks. The stress relaxation, which is linear in th...

We investigate the compression of nuclear matter in relativistic hydrodynamics. Nuclear matter is described by a σ − ω–type model for the hadron matter phase and by the MIT bag model for the quark–gluon plasma, with a first order phase transition between both phases. In the presence of phase transitions, hydrodynamical solutions change qualitatively, for instance, one-dimensional stationary com...