TECTONIC, VOLCANIC, AND HYDROTHERMAL EVENT SEQUENCE ON DECEPTION ISLAND (ANTARCTICA)

On the basis of the correlation between seismic tectonostratigraphic u nits, volcanism, and geochemical distribution patterns of sea-floor se diments on Deception Island (Antarctica), a regional tectonic extensio n is suggested to explain the sequence of volcanic and hydrothermal ev ents. The syncollapse caldera episode is composed of five tectonostrat igraphic units separated by progressively tilted and bent unconformiti es. Each unit shows a sequence of Quaternary volcanic cones and mound structures that display high contents of Fe, Mn, and Zn. As-rich activ e fumaroles and hot-spring areas are associated with the postcollapse episode and linked to normal faulting and present volcanism.