Submarine thermal springs associated with young volcanoes: The Teahitia vents, Society Islands, Pacific Ocean

Hydrothermal solutions were sampled close to two summits of Teahitia, a submarine volcano from the southern extension of the Society volcanic chain. The temperatures measured within two vents were 30°C. The vent solutions have a pH value around 5.3 and are enriched in Fe, Mn, Si, Ba, Li, and REEs relative to ambiant seawater but show only a small decrease in Mg and SO4 concentrations. The lowest measured 87Sr/86Sr is 0.70867, while the εNd is identical to those of the surrounding alkali basalt (+2.5). The vent solutions from Teahitia have chemical characteristics similar to Pele's vents, Loihi Seamount, another mid-plate volcano. The exact temperature of seawater basalt interaction is difficult to constrain. However, the absence of positive Eu anomaly in the fluids, the particles, and in the hydrothermal deposits from Teahitia seems to exclude the participation of a high-temperature component comparable as those involved in mid-ocean ridge-axis vents.