Intrinsic attenuation and scattering in laterally inhomogeneous sediments.

Surface Waves in Laterally Inhomogeneous Regions

The Physics of Sound Scattering From, and Attenuation Through, Compliant Bubbly Mixtures and Saturated Laboratory Sediments

The goal of this research is to acquire a quantitative understanding, leading to predictive models, of the broader aspects of linear and nonlinear sound scattering, transmission and coherency in oceanic sediments and bubbly mixtures pertinent to the shallow-water acoustics. Of particular interest is the delineation of different regimes of behavior as a function of frequency, bubble size distrib...

Separation of intrinsic and scattering seismic attenuation in the Southern Apennine zone, Italy

S U M M A R Y Scattered waves observed at the seismographs of the National Italy’s seismic network have been used to investigate the intrinsic dissipation and scattering properties of the lithosphere under the Southern Apennines, Italy. First, we investigate the coda-Q properties, then we apply the MLTW analysis in the hypothesis of velocity and scattering coefficient constant with depth, and f...

The Effect of Dynamic Permeability on Velocity and Intrinsic Attenuation of Compressional Waves in Sand

Stress waves contain useful information about the properties of porous materials; they can be recovered through different non-destructive testing methods such as crosswell, vertical seismic profile, borehole logging as well as sonic tests. In all these methods, it is crucial to assess the effects of frequency on wave attributes including velocity and intrinsic attenuation. The dependency of per...

Computer Simulation of Ion Beam Analysis of Laterally Inhomogeneous Materials

The program STRUCTNRA for the simulation of ion beam analysis charged particle spectra from arbitrary two-dimensional distributions of materials is described. The code is validated by comparison to experimental backscattering data from a silicon grating on tantalum at di erent orientations and incident angles. Simulated spectra for several types of rough thin layers and a chessboard-like arrang...