For laterally complex media, it may be more suitable to take a different orientation of thedisplacement vector of Shear-waves. This may change the sign of several imaginary reflections andconversion coefficients to be used in reservoir characterization and AVO (Amplitude Versus Offset)analysis or modeling. In this new convention the positive direction of the displacement vector ofreflected Shea...

Special features of surface gravity waves in deep fluid flow with constant vertical shear of velocity is studied. It is found that the mean flow velocity shear leads to non-trivial modification of surface gravity wave modes dispersive characteristics. Moreover, the shear induces generation of surface gravity waves by internal vortex mode perturbations. The performed analytical and numerical stu...

shear and compressional wave velocities along with other petrophysical logs, are considered as upmost important data for hydrocarbon reservoirs characterization. shear wave velocity (vs) in well logging is commonly measured by some sort of dipole logging tools, which are able to acquire shear waves as well as compressional waves such as sonic scanner, dsi (dipole shear sonic imager) by schlumbe...

A general formalism for computing the nonlinear interactions between triads of coastally-trapped gravity and vorticity waves is developed. An analysis of the linearized problem reveals that gravity (or edge) waves and vorticity (or shear) waves exist as members of the same non-Sturm-Liouville eigenvalue problem, with unstable shear waves representing the complex eigenvalue portion of the result...

The high-order harmonic-wave generation of ultrasonic shear waves has not yet been studied. We generated high-order shear harmonic waves and studied them in terms of the nonlinear wave mechanism associated with strain waves. When the shear waves propagated through highly dissipative MnCu20Ni5Fe2, TiNi, and Sn-3Al specimens and were reflected from the far side of the specimen, we observed high-o...

Direct numerical simulations (DNS) are performed to investigate the behaviour of a weakly stratified shear layer in the presence of a strongly stratified region beneath it. Both, coherent Kelvin–Helmholtz (KH) rollers and small-scale turbulence, are observed during the evolution of the shear layer. The deep stratification measured by the Richardson number Jd is varied to study its effect on the...

Head on collision of localized waves in cold and dense hadronic matter with and without shear and bulk viscosities is investigated. Non-relativistic dynamics of propagating waves is studied using the hydrodynamics description of the system and suitable equation of state. It will be shown that the localized waves are described by solutions of the Burgers equation. Simulations show that the propa...

In boreholes where formation shear velocity is lower than borehole tluid velocity neither refracted shear waves nor pseudo-Rayleigh waves can propagate. When frequency response of the sonde does not extend to low frequencies (e.g. 2 kHz) Stoneley waves are not excited efficiently. In such cases refracted P, leaking modes (PL) and tluid waves become dominant phases on a full waveform acoustic lo...

in this paper we are going to show the importance of mode identification in microtremor array analysis. the idea come from four concentric ambient noise array recordings with aperture 100 to 1000 meters, performed in southern urban area of tehran near the shrine of imam khomeini. these measurements were part of a comprehensive research project with the aim of determination of deep shear wave ve...

Using a recently developed reconstruction method for photoacoustic tomography (PAT) valid for a planar measurement geometry parallel to a layered medium, we investigate the effects of shear wave propagation in the solid layer upon the ability to estimate Fourier components of the object. We examine this ability as a function of the thickness of the layer supporting shear waves as well as of the...