ACOUSTIC STUDIES 



Research in acoustics from the tower is concerned with the 

 propagation of subsurface sound signals, and especially with bio- 

 logical and physical factors that interfere with propagation, trans- 

 mission, and reception. The investigations are centered in seven 

 primary areas: 



Biological factors 



Ambient sound 



Target identification 



Acoustic scattering 



Sound attenuation (plankton) 



Physical factors 



Sound attenuation (bubbles) 

 Sound velocity 

 Sound transmission 



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