Presence of large pumice blocks on Tierra del Fuego and South Shetland Islands shorelines, from 1962 South Sandwich Islands eruption

摘要

We report on the source of pumice found on beaches of Tierra del Fuego (Argentina) and the South Shetland Islands (Antarctica), north and south of the Drake Passage. Petrological studies, chemical analyses and experiments on this pumice indicate it is most likely from a 1962 submarine eruption in the South Sandwich Islands. Previous work stated that clockwise marine currents carried such pumice as far as Tasmania. Our findings show that the currents continued to transport the pumice to Drake Passage, nearly completing a circuit around Antarctica, and up to southern Argentina showing that this material can follow complex pathways for more than 20000 km.