West Florida Shelf Environment for the Area Characterization Test I (ACT I)
Abstract
During 18 through 27 September 1992, a carefully controlled acoustic exercise, Area Characterization Test 1 (ACT 1) was conducted in the shallow- water West Florida Shelf area known as Florida Middle Ground under the auspices of the Undersea Warfare Office of the Advanced Research Projects Agency. The goal is to develop an acoustic detection capability in adverse ocean environments such as shallow-water areas of continental shelves. To accomplish this, environmental data, which includes bathymetry, sediment samples, temperature and salinity of the water column, ocean currents and meteorological conditions, are provided for the interpretation of acoustic measurements. The test area is classified as a sandy-silt or sand-silt-day bottom with low carbonate content. Core and seismic data from other work shows the subbottom to be unconsolidated, comprised of Pleistocene to Recent sediments approximately 129 m thick at array locations. Evaluation of seafloor properties suggest that the area is homogenous, with a smooth water-sediment interface, and a high acoustic impedance. A geoacoustic model is derived from exercise measurements, Hamilton values, and archival seismic and core records. Potential for oceanographic variability is high due to wind induced circulation and interaction of shelf water with Loop Current water. While a typical summer mixed layer down to 30 m is evident in all profiles, a high temperature gradient at 150 m occurs near the array locations as part of a warm feature. Current data from meters placed on both vertical and horizontal One arrays at 79-m and 188-m water depths, respectively, appear to be dominated by the principal lunar and solar semidiurnal and diurnal components.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 08, 1994
- Accession Number
- ADA283516
Entities
People
- B. R. Gomes
- J. E. Matthews
Organizations
- United States Naval Research Laboratory