BROWNING: ENVIRONMENTAL FACTORS AFFECTING LOW FREQUENCY 

 PROPAGATION IN THE OCEAN 



ASSUME SPHERICAL SPREADING TO R^, 

 THEN CYLINDRICAL. 



N = 20 log R + 10 log ^ + OR 

 w o K^ 



10 log R + 10 log R + QR 



LET H = 10 log R 



N = H + 10 log R + OtR 

 w o 



WE PLOT: 



(N - 10 log R) = QR + H 

 w o 



Figure 2. SPREADING MODEL 



771 



