Head Waves, Helicopters, Ambient Noise, and Fine-Grained Sediment Acoustics
Abstract
This proposal addresses five research topics. 1) Theory of head waves in shallow-water, wind generated ambient noise for recovering" geo-acoustic properties of the seabed. 2) Analysis of ambient noise data collected on Deep Sound Mark II during the Sediment Charac"terization Experiment (SCE), conducted over the New England mud patch. 3) Theory of wave propagation in fine-grained sediments, as a"n extension of the grain-shearing model. 4) Experiment using helicopter-generated head waves for recovering the low-frequency (13 -" 3,500 Hz) geo-acoustic properties of shallow-water marine sediments. 5) Very-low-frequency (< 5 Hz), wind-generated ambient noise f"or recovering the geo-acoustic properties and sub-bottom stratification of the seabed in deep water. The common factor in all five topics is the geo-acoustic properties of marine sediments. Recovery of these properties from the spatial (coherence) properties ambie"nt noise is the theme of topics 1, 2 and 5. Development of a theory of the dispersion relations associated with compressional and sh""ear wave propagation in fine-grained (clays and silts) is the objective of topic 3. Measurements of the head wave in shallow water,"" as produced by the main rotor of a low-flying light helicopter, is topic 4, the aim being to recover the dispersion properties of t"he underlying sediment at frequencies as low as 13 Hz.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 20, 2018
- Source ID
- N000141812126
Entities
People
- Michael Buckingham
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego