Accession Number:

AD1049148

Title:

Acoustic Wave Dispersion and Scattering in Complex Marine Sediment Structures

Descriptive Note:

Technical Report,15 Mar 2014,31 Dec 2017

Corporate Author:

Pennsylvania State University Applied Research Laboratory University Park

Personal Author(s):

• Holland ,Charles W.

Report Date:

2018-03-21

Pagination or Media Count:

4.0

Abstract:

Major challenges in testing dispersion theories against measured data include separating the competing effects of structures that occur in virtually all natural marine sediments including discrete layering, gradients sound speed, attenuation and density, shear waves, interface roughness, sediment volume heterogeneities sub-wavelength scale, lateral variability many wavelength scale and anisotropy. All of these effects exhibit their own frequency dependence and if ignored, can badly bias dispersion estimates. One of the competing effects, sediment volume scattering, is important not only for establishing the correct frequency dependence of the attenuation, but also crucial for understanding long-range reverberation prediction. Recent evidence has suggested that sediment volume scattering is a dominant mechanism for controlling the frequency dependence of reverberation. The long-term goal of the research is to substantively improve understanding of the physical mechanisms that control propagation and scattering in the seabed.

Descriptors:

• Acoustic Waves
• acoustic scattering
• sediments
• geoacoustics
• heterogeneity
• acoustic propagation
• reverberation
• seabed
• roughness

Subject Categories:

• Physical and Dynamic Oceanography
• Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE