Sea-water samples collec- 

 ted adjacent to and be- 

 neath slicks are shaken 

 at known speed and time. 

 After this, the foam layer 

 is photographed every 2 

 seconds. The initial mean 

 diameter of bubbles in a 

 normal foam layer is about 

 0.5 mm. This diameter in- 

 creases to around 0.8 mm 

 after 10 seconds due to 

 coalescence. The mean 

 maximum diameter in- 

 creases from 1.8 to 2.7 mm 

 in the same time interval. 



1 



1 



I OUT 



1 7— 





' OF 







SLICK 



/ IN 



I I 



/ i 



/ SLICK 



i 



20 40 60 



FOAMING FACTOR (F) 



Water samples collected in slick areas produce 

 higher foaming factor values than samples col- 

 lected from outside the convergence area under 

 slicks. These samples were collected from near and 

 4 feet below the surface during July. 



TIME (SEC) 



Foam produced in water collected outside slicks 

 decays three times as rapidly as foam from nearby 

 slick areas. This indicates that water in and under 

 the slick zone contains more organic material, has a 

 higher foaming factor, and produces more stable foam. 



75 



