Inversion for Geoacoustic Model Parameters in Range-Dependent Shallow Water Environments
Abstract
The ability to predict sound propagation in shallow water is limited by the knowledge of the geoacoustic properties of the ocean bottom. The long term goals of this research are: (1) to develop full field inversion methods for estimating parameters of geoacoustic models of the ocean bottom and the associated uncertainties in the model parameter values; and (2) to evaluate the performance of the geoacoustic inversion techniques for applications over a broad frequency band in range dependent shallow water environments. This work is set within the wider context of research to understand the interaction of sound with the ocean bottom and determine the critical geoacoustic parameters that affect sound transmission in shallow water. The impact of variability in the sediment properties has been the focus of research in shallow water acoustics for several years. In SW06 a simple experiment based on a circular ship track around a vertical array was designed to study the azimuthal variation of geoacoustic model parameters. This report applies an inversion technique based on ray travel time of mid-frequency (1.1-4.5 kHz) sound signals to estimate geoacoustic profiles and study the heterogeneity of the sediment properties within the area of the circle. The approach is applied to circle data from two different sites that represented the two focal sites of the SW06 experiment: the MORAY site of ?outer shelf wedge? sediment that is clay-rich and stiff; and the SWAMI32 site where the outer shelf wedge sediment is overlain by a thin layer of medium sand. This work was done in collaboration with Dr. Y-M Jiang.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2010
- Accession Number
- ADA542155
Entities
People
- N. Ross Chapman
Organizations
- University of Victoria