The design and content of MSAT, a new Matlab toolkit for the study and analysis of seismic and elastic anisotropy, is described. Along with a brief introduction to the basic theory of anisotropic elasticity and a guide to the functions provided by the toolkit, three example applications are discussed. First, the toolkit is used to analyse the effect of pressure on the elasticity of the monoclin...

The goal of this study is to investigate the effect of the initial stress and transverse isotropy on the dispersion relation of flexural wave in a conducting circular cylinder subject to the initial state of stress of the form of hydrostatic tension or compression. The free stress conditions on the inner and outer surfaces of the hollow circular cylinder were used to form the dispersion relatio...

The unified theory for elastic wave propagation in polycrystalline materials, developed by Stanke and Kino [ J. Acoust. Soc. Am. 75, 665–681 (1984)], has been applied to compute the propagation constants in materials consisting of cubic crystallites with texture. The particular texture considered here is one in which one of the cube axes of each crystallite is aligned in a preferred direction w...

We provide a new interpretation of ultraviolet transition region emission line widths observed by the SUMER instrument on the Solar and Heliospheric Observatory (SOHO). This investigation is prompted by observations of the chromosphere at unprecedented spatial and temporal resolution from the Solar Optical Telescope (SOT) on Hinode revealing that all chromospheric structures above the limb disp...

We study the fracture surface of three dimensional samples through a model for quasi-static fractures known as Born Model. In particular, we consider the roughness of this fracture surface. We find for the roughness exponent a value ζ = 0.5 expected for “small length scales” in microfracturing experiments. Since this corresponds to a slow evolution for the fracture, our simulations confirm that...

Surface wave analysis is sometimes used in engineering investigations to obtain ground stiffness profiles by inversed modeling of dispersion velocities. Since dispersion data may be polarized due to material anisotropy, a thorough understanding of the dispersion property is necessary for the accurate reconstruction of inversion models. Based on the general constitutive relation of stress and st...

This note surveys the well-known structure of G-manifolds and summarizes parts of two papers that have not yet appeared: [4], joint with J. Brüning and F. W. Kamber, and [8], joint with I. Prokhorenkov. In particular, from a given manifold on which a compact Lie group acts smoothly, we construct a sequence of manifolds on which the same Lie group acts, but with fewer levels of singular strata. ...

An interesting feature of the Davies-Unruh effect is that a uniformly accelerated observer sees an isotropic thermal spectrum of particles even though there is a preferred direction in this context, determined by the direction of the acceleration g. We investigate the thermal fluctuations in the Unruh bath by studying the Brownian motion of particles in the bath, especially as regards to isotro...

A persistent reversal in the expected polarity of the initiation of vertically polarized shear waves that graze the D'' layer (the layer at the boundary between the outer core and the lower mantle of Earth) in some regions starts at the arrival time of horizontally polarized shear waves. Full waveform modeling of the split shear waves for paths beneath the Caribbean requires azimuthal anisotrop...

A general analysis of poroelasticity for vertical transverse isotropy (VTI) shows that four eigenvectors are pure shear modes with no coupling to the pore-fluid mechanics. The remaining two eigenvectors are linear combinations of pure compression and uniaxial shear, both of which are coupled to the fluid mechanics. After reducing the problem to a 2 × 2 system, the analysis shows in a relatively...