Tritium concentrations have been determined for seawater samples collected near the western boundary of the South Pacific. The deepest penetration of tritium, in terms of either depth or isopycnal surface, occurs between latitudes 14 and 30S and the penetration is greater than that observed in the mid-South Pacific during the Geochemical Ocean Sections Study (GEOSECS) cruise....
Harries, J. R., and G. E. Calf. 1982. "Input of tritium to intermediate depth water in the South Pacific." Journal of Marine Research 40, (3). https://elischolar.library.yale.edu/journal_of_marine_research/1612