Accession Number:

AD0781869

Title:

Bottom Reflectivity Experiments in the Deep Ocean over Rugged Bottom Terrain

Descriptive Note:

Final rept.

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

• Robinson, Jr., A. Z.
• Roche, Jr., Lynn B.
• Sabin, Gerald A.

Report Date:

1974-06-25

Pagination or Media Count:

47.0

Abstract:

In bottom-reflectivity experiments conducted in the Atlantic Ocean during September and October 1971, 12-lb blocks of TNT were used as the acoustic source. Data were collected from a hydrophone suspended 500 ft off the ocean floor. The experiments were designed so that direct and reflected signals incident on the suspended hydrophone could be separated in time. Recorded data were digitized, and energy spectral densities of the direct and the reflected signals then were computed separately by fast Fourier transform FFT techniques and plotted on the same linear scale to show the bottom-reflection effects as a function of frequency. The experimental procedures are critically examined to expose their inadequacies and to provide information to future experimenters.

Descriptors:

• *ACOUSTIC REFLECTION
• *OCEAN BOTTOM TOPOGRAPHY
• *UNDERWATER SOUND
• ACOUSTIC REFRACTION
• ATLANTIC OCEAN
• BATHYMETRY
• DATA REDUCTION
• FOURIER ANALYSIS
• HYDROPHONES
• SEDIMENTS
• UNDERWATER SOUND SIGNALS

Subject Categories:

• Physical and Dynamic Oceanography
• Acoustic Detection and Detectors
• Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE