Mapping of geoacoustic properties of sediments in shallow water

Range dependent geoacoustic properties of shallow water sediments were estimated using tomographic inversion techniques. Non-linear inversion schemes based on global optimization schemes were used. Synthetic data generated for assumed environmental conditions were analyzed using wavelets to obtain the modal arrivals for frequencies in the range 10-180 Hz. Data from a number of sources distributed over an area were used to estimate the bathymetry and the compressional wave speeds in the sediment. The inversion scheme was based on matching the group speed dispersion of the explosive signals and those corresponding to the replica models. Propagation was modeled using adiabatic theory. A posteriori error estimates in the form of standard deviations are also presented in this study.