iTO&P --■■■■■■-■ v Wki^ 



a. Near structure, shallow towfish 



*— P& 



AREA SEEN BY SIDE-SCAN 

 SONAR IMAGE 



SHADOWS, NOT SEEN, 

 OR POORLY SEEN BY 

 SIDE-SCAN SONAR IMAGE 



b. Beyond toe, deep towfish 

 Figure 39. Example of two side-scan sonar inspection passes 



65 



