Long-Range Acoustic Propagation in the Shallow Bering Sea.

Abstract

Propagation measurements were obtained with explosives and CW signals of 58,350,700, and 1300 Hz in 25-fathom waters of the Bering Sea. Sound was received by an anchored string of 14 hydrophones spaced vertically at 10-ft intervals. Measurements to ranges of 80 kyd were confined to areas that had previously been surveyed acoustically to determine sediment properties and thicknesses. CW tones exhibited amplitude fluctuations of 50 dB with attendant frequency spreading. Empirical equations ar presented describing resultant half-power spectra as a function of range and frequency. Pressure levels, each based on 6000 to 10,000 data points, demonstrated a hydrophone depth dependence with minimal evidence of mode-stripping. Propagation anomalies for 700 and 1300 Hz agree with energy flux density procedures, provided a sufficiently low attenuation in the bottom is assumed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1972
Accession Number
AD0745735

Entities

People

  • Kenneth V. Mackenzie

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Propagation
  • Amplitude
  • Attenuation
  • Bering Sea
  • Equations
  • Explosives
  • Flux Density
  • Frequency
  • Hydrophones
  • Intervals
  • Mathematics
  • Measurement
  • Power Spectra
  • Sediments
  • Spectra
  • Thickness

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Oceanography.

Technology Areas

  • Space