ABSTRACT
Epithermal-style and transitional shallow submarine hydrothermal systems were discovered at recently active volcanic centers along the Tonga-Kermadec Arc, SW-Pacific. Notable enrichments in As, Sb, Hg, Ag, and Au, low base metal contents, characteristic alteration patterns and sulfur isotope ratios resembling precipitates from volcanic subaerial hot springs suggest contributions from magmatic sources. The growing number of discoveries of epithermal-style mineralisation in shallow submarine hot springs have significant implications for land-based mineral exploration in ancient volcanic belts, which are traditionally targeted for volcanogenic massive sulfide deposits but are largely unexplored for epithermal-type mineralisation.
