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P. Borejko:
"A generalized ray model of three-dimensional propagation on the continental shelf including shear wave effects in an absorptive bottom";
Vortrag: The 11th International Conference on Theoretical and Computational Acoustics, College Station, Texas, USA (eingeladen); 10.03.2014 - 14.03.2014.

The traditionally used model of the propagation of sound in a shallow water environment is that of an acoustic wave mode in a flat layer of fluid over a fluid or an elastic half-space [the Pekeris model (1948)]. On the continental shelf, the sound may be three-dimensional (3-D) due to the sloping bathymetry; and the Pekeris model, in which acoustic propagation is two-dimensional, may no longer be accurate. A representative model for a sloping-bottom environment is that of the canonical wedge.
Acoustic propagation in the canonical wedge has been analyzed by applying various modeling approaches since the early 1980s, but there have been few observations of the predicted 3-D propagation effects. In 2007 and 2008, the 3-D propagation was quantitatively measured in a pair of acoustic transmission tests on the Florida shelf, shaped nearly as the canonical wedge; and accurately modeled in 2012 by applying 3-D hybrid and normal-mode based approaches.
In this paper, the generalized ray method is applied to acoustic propagation calculations in a canonical wedge consisting of a wedge-shaped water layer over an exposed (devoid of loose sediment) low-loss limestone bottom, where the shear wave speed is slightly less than the speed of sound in water. The generalized ray model predicts that cross-slope propagation in a canonical wedge may indeed be 3-D.
The predicted 3-D propagation effect is that some acoustic signals coming in along paths of multiple bottom interactions (the so-called "in-shore refracted paths"), propagating up the slope and back to the receiver, may substantially be stronger than those coming in along paths of only a few bottom interactions (the so-called "direct paths"), traveling near the straight source-to-receiver path that is parallel to the wedge apex. As a result, the practical determination of source location (bearing, distance, and depth) can be affected. This theoretical prediction is consistent with observations of two distinct signal arrivals in the above-mentioned tests: one signal coming in along the direct path; and the other, sometimes substantially stronger than the direct arrival, coming in later along the in-shore refracted path.

Acoustics, Coastal Wedge, 3-D Propagation

http://publik.tuwien.ac.at/files/PubDat_235298.pdf