Preliminary Analysis of Low-Frequency Backscatter Data from the Blake Escarpment
Abstract
Geoacoustic data in the Northern Blake-Bahama Basin by the Naval Oceanographic and Atmospheric Research Laboratory's (NOARL's) Deep Towed Acoustics/Geophysics System (DTAGS) are used to estimate the distribution and strength of acoustic energy backscattered sources on the Blake Escarpment is shown with scatter sections that present data steered at 0 deg (normal to the array) and -90 deg (endfire). The variability of the acoustic response of a promontory on the escarpment is shown on shot-by-shot basis along the profile using frequency-wavenumber analysis. Migrated data (i.e., where scattered energy has been transformed to the appropriate scattering surface) are used to estimate the size and distribution of scatters; strong scatters with lengths on the order of 100 m to over 1 km are identified. Low frequency (250 to 650 Hz) scattering strengths of -27 dB/M squared are shown to be appropriate for discrete scattering zones resolved with these data. This preliminary analysis of pure- path geoacoustic data demonstrates that such data can be used to obtain detailed information about the spatial distribution, size, and strength of seafloor scatters.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1990
- Accession Number
- ADA226492
Entities
People
- J. F. Gettrust
- M. M. Rowe
Organizations
- United States Naval Research Laboratory