E. C. Shang
Y. Y. Wang
CIRES, Univ. of Colorado/NOAA/Environmental Tech. Lab., Boulder, CO 80303
The seabottom often has a thin layer on its top and the sound speed in this thin layer is less than in water. It has been found that this thin layer can significantly effect the acoustic field in water column. First, it changes the bottom reflection character, and, on the other hand, it changes the modal wave-number difference: D[sub mn]=2(pi)(k[sub m]-k[sub n])[sup -1]. Those two factors determine the basic features of the acoustic field---the modal interference pattern and the modal attenuation rate. Based upon the sensitivity analysis, bottom parameter estimation scheme is proposed.