and 200 meters for September and October. At both depths, salinities 

 varied only about 0.2 %>o . In September, surface salinities increased 

 to the southeast with the isohalines oriented perpendicular to the 

 California coast. At the surface in October, and at 200 meters for 

 both months, salinities were slightly lower over the San Nicolas 

 Basin, but they increased to the northeast and southwest. No significant 

 orientation of isohalines is evident. 



C. Dissolved Oxygen. 



Dissolved oxygen determinations were made only on the September 

 grid stations. In most cases, a mixed layer existed in the upper 

 15 meters. Below this layer, oxygen content increased sharply to 

 a depth of 25 meters and then decreased steadily to a minimum at 

 about 675 meters. k typical oxygen concentration profile is presented 

 in Figure 9. 



c 



100 

 200 

 300 

 400 

 500 

 600 

 700 

 a: 800 

 2 900 

 1000 

 1100 

 1200 

 1300 

 1400 

 1500 



OXYGEN CONCENTRATION 

 MLA. 

 1.0 2.0 '3.0 4.0 50 60„ 



























-300 



-600 



-900 



-1200 



- 1500 



-1800 



-2100 



-2400 



-27001- 



-3000 11 " 



-3300 



-3600 



-3900 



-4200 



-4500 



-4800 



-5100 























































































































































































































































































































Grid station No. 21 

 22-26 September 1965 























































FIGURE 9. REPRESENTATIVE OXYGEN VERSUS DEPTH PROFILE 



Horizontal distributions of oxygen at the surface and 200 meters 

 are shown in Figure 10. North of San Nicolas Island, an area of 

 lower dissolved oxygen concentration was observed at both depths. 



11 



