Station 72, located in the Bellingshausen Sea (71°29'S, 094°00'W), had a 
surface temperature of -1.80°C, decreasing slightly below surface and increasing 
again to -1.70°C at 75 meters. Another decrease to -1.80°C was observed at 125 
meters. Below this a positive gradient, as noted on the other stations, but with a 
less pronounced slope, occurred to maximum sampling depth of 525 meters. Water 
temperatures were colder than in the Amundsen Sea area. The salinity profile is 
similar to those at stations 27 and 49, but with less prominent positive gradients at 
the transition zones. Surface salinity was 33.76 and 34.699, at 525 meters. 
Oxygen values in the upper 100 meters were less than those at corresponding depths 
in the Amundsen Sea and Cape Colbeck areas but followed the same general pattern. 
Below this, a lesser gradient was observed to 525 meters, where the profiles for all 
stations merge. Surface oxygen was 7.02 ml/I. 
Station 79 was selected for comparison because of its location at 70°51'S, 
101°54'W, between the Amundsen Sea and Bellingshausen Sea stations and because 
of its intermediate depth. A nearly isothermal layer extended to 100 meters with a 
surface temperature around -1.80°C. Below this was found the same positive temper- 
ature gradient as seen at stations 27 and 49, but this section of the profile plotted 
between the two stations. Below 500 meters, temperatures were 0.1 to 0.2°C colder 
than those of corresponding depths on station 27, and about 0.5°C colder than those 
of station 49 in the Amundsen Sea. Near-bottom temperature at 2, 300 meters was 
0.45°C. Salinities in the upper 50 meters were lower at this station than at the other 
three stations. A surface value of 33.299, was recorded. From 50 meters to about 
600 meters, salinity values plotted between those for the Amundsen and Bellingshausen 
Seas; below 600 meters to the bottom salinity values were the same as those for the 
other representative stations. Oxygen values followed the same pattern in the upper 
550 meters and below this were slightly higher than at stations 27 and 49. 
In summary, Antarctic Surface Water with temperatures below 0°C was observed 
in the upper 25 meters, with a slight temperature decrease just below the surface. 
This water mass was nearly isosaline in the Cape Colbeck area and north of Thurston 
Island; salinities decreased slightly immediately below the surface in Amundsen and 
Bellingshausen Seas. The seasonally lower surface salinities are attributed to summer 
ice melt, which also resulted in low surface densities, in some cases a sigma-t value 
less than 27.00. Dissolved oxygen values were high, ranging between 7.00 and 
9.00 ml/I. 
Below the Antarctic Surface Water the transition layer was located between the 
variable Surface Water and the more homogeneous Winter Water. This is most notice- 
able in the salinity and oxygen profiles by the steep positive salinity and negative 
oxygen gradients between 25 and 75 meters. This transition layer overlays Antarctic 
Winter Water with slight temperature variations in the different areas, while the 
lower limits of this water mass varied between 75 meters in the Amundsen Sea area to 
40 
