title: Nonlinear frequency-dependent attenuation in sandy sediments.
abstract: This paper summarizes evidence of a nonlinear frequency dependence of attenuation for compressional waves in shallow-water waveguides with sandy sediment bottoms. Sediment attenuation is found consistent with alpha(f) = alpha(f(o)) x (f/f(o))n, n approximately 1.8 +/- 0.2 at frequencies less than 1 kHz in agreement with the theoretical expectation, (n = 2), of Biot [J. Acoust. Soc. Am. 28(2), 168-178, 1956]. For frequencies less than 10 kHz, the sediment layers, within meters of the water-sediment interface, appear to play a role in the attenuation that strongly depends on the power law. The accurate calculation of sound transmission in a shallow-water waveguide requires the depth-dependent sound speed, density, and frequency-dependent attenuation.
authors.forename: J D
authors.initials: JD
authors.lastname: Holmes
authors.forename: W M
authors.initials: WM
authors.lastname: Carey
authors.forename: S M
authors.initials: SM
authors.lastname: Dediu
authors.forename: W L
authors.initials: WL
authors.lastname: Siegmann
mesh_terms: D003627:Data Interpretation, Statistical; D009038:Motion; D017711:Nonlinear Dynamics; D010507:Periodicity; D012822:Silicon Dioxide; D013016:Sound; D014867:Water
chemical_list: D014867:Water; D012822:Silicon Dioxide