Nonlinear Properties of In-Situ Sediment Gas Bubbles.
Abstract
A model for difference frequency backscatter from trapped bubbles in sandy sediments is developed. A nonlinear volume scattering coefficient is computed via a technique similar to that of Ostrovsky and Sutin ('Nonlinear sound scattering from subsurface bubble layers', in Natural Physical Sources of Underwater Sound, B. R. Kerman (ed.), 363-373 (1993)) which treats the case of bubbles surrounded by water. The Biot theory is incorporated to model the acoustics of sandy sediment. Biot fast and slow waves are included by modeling the pore fluid as a superposition of two acoustic fluids with effective densities that differ from the pore fluid's actual density and account for its confinement within sediment pores. The principle of acoustic reciprocity is employed to develop an expression for the backscattering strength.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 21, 1995
- Accession Number
- ADA309108
Entities
People
- Frank A. Boyle
- Nicholas P. Chotiros
Organizations
- University of Washington