FREQUENCY 31 Hz 

 SOURCE 500 ft 



RECEIVER 10800 ft 



100 y 



^110.. 



CO 



3 120.. 

 130.- 



^^'^^Wkw.**^ 



100 y 

 ^110 -- 



CD 



3120 ■- 

 130 ■- 



CO 



■a 



100 J 

 110 -- 

 120 -■ 

 130 -- 



i^'M%> 



25" N 30" N 35" N 40" N 45" N 50" N 55' N 60° N 



Figure 16. Propagation Loss versus Range for a 10, 800-ft Receiver Depth, 

 a 500-ft Source Depth, and a 31-Hz Frequency 



120 



