h3 



10-2 



BROCKS ('59) .t>.x- 

 \ (BALTIC) O^ 



kW "^or^^^^^ 



ROLL (1948) 

 o /BROCKS (1959) 



" ^ * fMORTU CCj 



(NORTH SEtf 



10-6 





PORTMAN (I960) 



10- 



10 20 30 40 50 



FRICTION VELOCITY Ujit CM/SEC 



