Wide Range and Broad Band Seabed Acoustic Model
Abstract
Approved for Public ReleaseAbstract: Within the long-term goal of an acoustic model of the seabed that covers a wide range of seabed types, and all relevant frequencies, in support of MCM and ASW needs, three interconnected tasks are proposed. First, a seabedacoustic model for a wide range of sediment types and frequency dependencies, with a reduced input parameter set, and consistent with experimental measurements. This builds upon achievements in the current funding cycle, which includes the identification of salinity as key input parameter in soft sediments, and the development of a new model based on the generalized squirt flow process that is capable of tracking the frequency dependence of the acoustic properties of both marine sand and mud sediments. Second, an adaptation of the seabed model to the arctic environment, taking account of the unique nature of the arctic seabed. Acoustic transmission data from under-ice experiments, including the CAATEX experiment, will be usedto invert for the properties of the arctic seabed, in collaboration with NERSC, Norway. At the same time, the under-ice propagation loss due to the ice keels will be addressed, in as far as the effects of the seabed and the ice are connected. Third, an adaptation of the model to account for variability due to benthic habitat and biological activity that may change with time. Unfortunately, a previous collaboration with Southampton University, UK, on a laboratory experiment to connect the presence of invertebrates to changes in acoustic properties, was halted by the pandemic anddid not restart due to loss of staff at Southampton, but the problem remains. New collaborations with in-situ benthic monitoring projects, including the GeoHab community and the National Oceanography Centre, UK, to develop connections between seabed acoustic properties and changes in the benthic habitat will be explored.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 15, 2023
- Source ID
- N000142312522
Entities
People
- Nicholas Chotiros
Organizations
- Office of Naval Research
- United States Navy
- University of Texas at Austin