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Geoacoustic inversion by mode amplitude perturbation.
Travis L Poole1, George V Frisk, James F Lynch
1Woods Hole Oceanographic Institution, Gigelow 209, MS#12, Woods Hole, Massachusetts 02543, USA. travis.poole@ed.ac.uk
The Journal of the Acoustical Society of America
|February 6, 2008
Summary
This study presents a new algorithm for analyzing seafloor acoustic properties using modal amplitudes. This method enhances previous techniques by incorporating more data for improved accuracy in acoustic inversions.
Area of Science:
- Oceanography
- Acoustics
- Geophysics
Background:
- Perturbative inverse methods are established for estimating seafloor acoustic properties in sediments.
- Previous methods primarily utilized modal eigenvalues as input data, limiting comprehensive analysis.
Purpose of the Study:
- To introduce a novel perturbative inversion algorithm for determining seafloor acoustic properties.
- To expand upon existing methods by incorporating modal amplitudes as input data.
Main Methods:
- The algorithm employs a series of approximate, linear steps to solve the nonlinear inverse problem.
- It utilizes modal amplitudes as the primary input data for inversion.
Main Results:
- The developed method demonstrates feasibility through applications to both synthetic and experimental data.
- The study validates the effectiveness of using modal amplitudes in acoustic property determination.
Conclusions:
- The new algorithm offers a more robust approach to seafloor acoustic property estimation.
- Combining modal eigenvalue and amplitude perturbation provides a comprehensive inversion strategy using all available modal data.
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