INTERPRETATION OF FREQUENCY-DEPENDENT TRANSMISSION-LOSS INTERFERENCE PATTERNS

Experimental observations of broad-band acoustic propagation in a know n geological region of the Atlantic Generating Station (AGS) site [1] has prompted a new approach to understanding frequency-dependent behav ior in shallow-water regions, A modal-based theory is presented to exp lain quantitatively the interference patterns of transmission loss ver sus frequency observed in the experimental data. It is shown that the higher modes are responsible for observed interference patterns and th at these can be related to modal group velocities using an ideal waveg uide model, This may provide new insights applicable to existing inver se techniques.