BATHYPELAGIC SQUID BATHYTEUTHIS 113 



The distribution of captures on the salinity section shows that most 

 of the points lie below the 34.G0%o isolialine. The three points on 

 or shallower tlian this line actually had simultaneous salinities greater 

 than 34.64%o. So all captures are in the high salinity range of Antarctic 

 Circumpolar Water. The salinity values for the three shallowest speci- 

 mens probably are not accurate and the plots of the sigma-t values are 

 too low. All captures were made in densities greater than about 

 sigma-t= 27.60. 



Where oxygen data are available the plots of captures generally 

 fall within the low to middle range of values, between about 3.80 ml/L 

 and 4.20 ml/L. Two captures were made at high values between 4.80 

 ml/L and 5.50 ml/L. 



To summarize, the captures plotted on the 55 °W sections were made 

 mainly at temperatures beween 1.5° and 2.25°, at high salinities close 

 to the maximum, at fairly high densities, and at low to moderate 

 oxygen concentrations. 



65** West Longitude; 56° to 63° South Latitudes 



The sections along 65 °W extend across the Drake Passage from the 

 South Shetland Islands to Tierra del Fuego. The oceanographic 

 data were taken in late w'inter during Eltanin Cruise 4. The Antarctic 

 Convergence is located on the temperature section between 58° and 

 59°S (fig. 27). The Subantarctic Surface Water north of the con- 

 vergence represents the beginning of the Falkland Current. Cores of 

 "warm" water (2.5°-4° C) pass along the edge of the South American 

 continental shelf; the bottom of the 2.5° isotherm is located at about 

 1700 m. The 2° isotherm is at the surface in the convergence zone; 

 below the surface at 250-400 m it passes southward past 61° S, descends 

 to about 800 m, then turns sharply northward forming a long tongue of 

 2° C water that protrudes to the south. It slopes gradually northward 

 from 1000 m at 59° S to about 1800 m on the bottom at 56°30'S. Below 

 61°S the water is below 2° C at all depths. Beneath the 2° isotherm 

 the water shows gradual cooling to temperatures less than 0.5° C 

 toward the bottom. 



The salinity section shows a well-stratified salinity structure across 

 the Drake Passage (fig. 28). The isohalines originate close to the sur- 

 face at 68 °S, but they get progressively deeper toward the north. The 

 34.60%o isohaline originates on the section in about 250-300 m at 63 °S 

 and slopes down to al)Out 1300 m at 56°30' S. A well-defined core of 

 high salinity occurs at depths of 1100 to 2100 m between 57° and 

 62° S; values in the core are 34.73%o to 34.74%o. At 62°S a small core 

 of 34.74%o water lies between 600-1000 m. Below the salinity maxi- 

 mum the isohaline for 34.72%o crosses the Passage between 2000 and 

 2500 m with a dip to 2900 m at 58° S. 



