The purpose of this research was to test the proposition that the mantle beneath New York and Southern New England is divided into several "anisotropic domains" that are the seismic expression of the plate tectonic process of "terrain accretion". Were such the case, we would expect different directions of the shear wave fast direction and different mean shear wave velocities in each of the seve...

In this article, we analyze the dynamic characteristics of head wave in multi-layered half-space media models with high-velocity layer or low-velocity layer, and the model with a continuous transition-zone between the crust and the mantle by using synthetic seismogram. It is concluded that the dynamic characteristics of head wave are sensitive to the thickness and velocity of the high-velocity ...

Within the context of seismic wave propagation, fractures can be described as thin layers or linear-slip interfaces. In this paper, numerical simulations of elastic wave propagation in a medium with a single fracture represented by these two models are performed by 2D finite-difference codes: a variable-grid isotropic code for the thin-layer model and a regular-grid anisotropic code for the lin...

The paper outlines a probabilistic basis for the automatic estimation from observed surface wave dispersion of structural model parameters with uncertainties. Given an earth model, a wave type and pertinent parameter values, the group velocity of seismic waves can be computed from theory as a function of frequency. Such a function may also be based on the dynamic spectrum representation of an e...

The analysis of crosswell seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded 2000 feet above the reservoir. The first is that the dominant late phases on the records are the tube waves generated in the source well and later converted into laterally propagating waves through the reservoir in gas/water saturated layers, which convert back to tubew...

ABSTRACT: Frequent occurrence of seismic activities has drawn attention of various researchers, cutting across science and engineering discipline. The domain of earthquake geotechnical engineering has extended from determination of attenuation of seismic wave to providing suitable foundation under liquefied and unliquefied soil conditions. The seismic data can be fully intrepreated by use of se...

An angle-dependent reflection coefficient is recovered by seismic migration in the angle domain. We have developed a postmigration technique for computing scattering and dip angle common-image gathers (CIGs) from seismic images, extended by the subsurface offset, based on wave-equation migration methods. Our methodology suggests a system of Radon transform operators by introducing local transfo...

An angle-dependent reflection coefficient is recovered by seismic migration in the angle-domain. We propose a post-migration technique for computing scattering and dip angle common-image gathers (CIGs) from seismic images, extended by the subsurface offset, in relation with wave-equation migration methods. Our methodology suggests a system of Radon transform operators by introducing local trans...

We study the interaction of a seismic wave-field with a spherical acoustic gasor fluid-filled cavity. The intention of this study is to clarify whether seismic resonances can be expected, a characteristic feature, which may help detecting cavities in the subsurface. This is important for many applications, as in particular the detection of underground nuclear explosions which are to be prohibit...