ASA 125th Meeting Ottawa 1993 May

2aUW8. Application of numerical grid generation to scattering from rough penetrable ocean bottoms.

Kenneth E. Gilbert

Timothy J. Kulbago

Appl. Res. Lab. and the Grad. Prog. in Acoust., Penn State Univ., P.O. Box 30, State College, PA 16804

Xiao Di

Univ. of Mississippi, University, MS 38677

Natl. Res. Council, Ottawa, ON K1A 0R6, Canada

Numerical grid generation methods have recently been applied with success to atmospheric sound propagation over irregular terrain [Di et al., J. Acoust. Soc. Am 92, 2431 (A) (1992)]. Here, the method was applied to scattering from rough ocean bottoms that allow sound to penetrate into the sediment. Considered are some simple geometries for which analytic results exist as well as more complex geometries that are treated numerically. Of interest are the relative contributions from surface scattering and volume scattering to the total acoustic backscatter. The ultimate objective of the investigation is to arrive at a simple, physically intuitive formulation that will aid in the interpretation of backscatter data from complex coastal environments. [Work supported by ONR.]