Observations and modeling of range-dependent propagation in low-frequency tones emitted by a container shipa)
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View abstract on PubMed
Summary
This summary is machine-generated.Researchers studied seabed properties on the New England Mud Patch using low-frequency tonal emissions. They modeled sound propagation to estimate compressional wave attenuation in deep sediments, finding it to be 0.17±0.03 dB/λ at 16 Hz.
Area Of Science
- Ocean acoustics
- Marine geophysics
- Seismic signal processing
Background
- The New England Mud Patch features a low sound speed mud layer.
- Understanding seabed properties is crucial for acoustic propagation modeling.
Purpose Of The Study
- To investigate seabed properties, specifically compressional wave attenuation, in the New England Mud Patch.
- To utilize low-frequency tonal emissions from a merchant vessel for geoacoustic inversion.
Main Methods
- Forward-modeling of acoustic data using adiabatic normal modes.
- Development of a range-varying geoacoustic model for upper sediments.
- Bayesian inversion to estimate frequency-dependent compressional wave attenuation in deep sediments.
Main Results
- Successfully reproduced acoustic mode interference patterns using the geoacoustic model.
- Estimated compressional wave attenuation in deep sediments at 16 Hz to be 0.17±0.03 dB/λ.
- Inclusion of elastic effects in models reduced estimated compressional wave attenuation by 10%-40%.
Conclusions
- The study provides valuable insights into the geoacoustic properties of the New England Mud Patch.
- Accurate modeling of elastic effects is important for precise attenuation estimates.
- Low-frequency acoustic emissions can effectively probe deep sediment properties.
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