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Updated: Jun 24, 2025
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Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
Published on: June 27, 2013
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Feature-based maximum entropy for geophysical properties of the seabeda).
D P Knobles1, William Hodgkiss2, Jason Chaytor3
1Platt Institute of Nuclear Physics, P.O. Box 27200, Austin, Texas 78755, USA.
The Journal of the Acoustical Society of America
|June 3, 2024
Summary
Seabed geophysical properties influence acoustic signal interference. Feature-based inversion of acoustic data reveals a sandy seabed with specific porosity, aiding acoustic propagation predictions.
Area of Science:
- Ocean acoustics
- Geophysics
- Inversion methods
Background:
- Acoustic propagation in the ocean is affected by seabed properties.
- Seabed reflections create interference patterns in acoustic signals.
- Understanding these patterns aids in geophysical characterization.
Purpose of the Study:
- To analyze acoustic data for seabed property inversion.
- To utilize feature-based inversion on vertical line array (VLA) data.
- To characterize the New England continental shelf break seabed.
Main Methods:
- Feature-based inversion of acoustic data.
- Ray-based analysis of direct and bottom-reflected paths.
- Application of the viscous grain shearing (VGS) model for seabed parameterization.
- Normal mode modeling for range-scale predictions.
Main Results:
- Identified acoustic features (frequency nulls) sensitive to seabed properties.
- Inferred a two-layer seabed model, likely sand with ~0.42 porosity.
- A thin surface layer with slightly higher porosity (~0.45-0.50) is possible.
- VGS parameters were estimated from short-range data.
Conclusions:
- Feature-based inversion effectively characterizes seabed properties.
- The VGS model provides a viable parameterization for seabed acoustics.
- Acoustic data can predict received levels over extended ranges.
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