Consistency and reliability of geoacoustic inversions with a horizontal line array

Geoacoustic inversions with a towed horizontal array are of interest for rapidly characterizing sediment properties over changing regions. To be of practical value, inversions must yield consistent and reliable results for consecutive or neighboring data. A method of determining inversion reliability a priori is delineated using an empirical approach and confirmed with inversion results in terms of consistency. Geoacoustic parameter hierarchy and resolvability are empirically analyzed using two different methods: one requires knowledge of the source function and the other does not. Inversion results using the two methods are compared using both synthetic data and experimental data from MAPEX2000. The inversions employ a global optimization technique which navigates the parameter space in directions aligned with valleys of the cost function, increasing inversion algorithm efficiency and disclosing parameter correlations and hierarchy. (c) 2006 Acoustical Society of America.