Naval Electronic Systems Command Research Articles

Experimental Investigation of a Sub-Bottom Reflecting Layer in the Deep Ocean

The existence of a subbottom reflecting layer is indicated by acoustic measurements made about 50 miles south of Bermuda, in the vicinity of moored hydrophones several hundred feet above the bottom. A transducer located on the bottom at a range of 2400 ft generated acoustic signals in the frequency range 400–1000 Hz. Interference effects were observed in the reception at the various receivers. Interpretation of the data in terms of a simple model indicates that there is a subbottom reflecting layer more than 100 ft below the nominal ocean bottom. [Work was supported by the U. S. Naval Electronic Systems Command.]