Accession Number : ADA017360

Title :   Bottom Reflection Model Validation with Measured Data from FASOR III (Forward Area SOnar Research) Stations in the Pacific and Indian Oceans.

Descriptive Note : Final rept. Jan 73-Sep 74,

Corporate Author : NAVAL UNDERSEA CENTER SAN DIEGO CALIF

Personal Author(s) : Morris,Halcyon E.

Report Date : JUL 1975

Pagination or Media Count : 74

Abstract : Calculated and experimental results are compared for thirteen stations of the third Forward Area SOnar Research Cruise(FASOR III) for which bottom loss data are available. The mathematical model determines theoretical bottom reflection losses which depend on sediment layering with absorption and sound speed gradients in the sediment layers. The sea-floor sediments were assumed to be an absorbing-liquid sediment with complex velocity. Sediment core and geoacoustic measurements provided sediment properties for the mathematical model. Agreement of results is good for a wide range of sediment structures at frequencies ranging from 0.05 to 4.0 kilohertz. Poor agreement for a few stations at the lower frequencies and grazing angles is attributed to the difficulty of interpreting the experimental data because of multipaths.

Descriptors :   *Acoustic reflection, *Sonar signals, *Acoustic attenuation, Ocean bottom, Sediments, Acoustic velocity, Mathematical models, Pacific Ocean, Indian Ocean

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE