The distribution of oxygen in an area of the South Atlantic Ocean has been studied. The area is limited by the Argentinian continental slope and the 45º W meridian and from 35º S to 47º S. The distribution of oxygen in studied in relation with the salinity distribution in seven horizontal levels and one vertical profile. The oxygen distribution in the area of the Subtropical Convergence has a characteristic pattern that seems to be very useful in the determination of the Convergence. The Subtropical Convergence was situated between the oceanographic station where was found the maximum salinity and the maximum oxygen (negative) horizontal gradients. The maximum fluctuation of the Subtropical Convergence area is situated immediately East of Malvinas Current, where its desplacement N-S between winter and spring is, at least, 200 nautical miles. The water sunk at the Subtropical Convergence can be followed by its oxygen content. The intermediate maximum of oxygen is not coincident with the depth of salinity minimum characteristic of the núcleos of S. A. waters. A hipothesis to explain this is given.
