Explosive eruptive history of Pantelleria, Italy: Repeated caldera collapse and ignimbrite emplacement at a peralkaline volcano

A new, pre-Green Tuff (46 ka) volcanic stratigraphy is presented for the peralkaline Pantelleria Volcano, Italy.New 40Ar/39Ar and paleomagnetic data are combined with detailed field studies to develop a comprehensivestratigraphic reconstruction of the island.We find that the pre-46 ka succession is characterised by eight silicarichperalkaline (trachyte to pantellerite) ignimbrites,many ofwhich blanketed the entire island. The ignimbritesare typically welded to rheomorphic, and are commonly associated with lithic breccias and/or pumice deposits.They record sustained radial pyroclastic density currents fed by lowpyroclastic fountains. The onset of ignimbriteemplacement is typically preceded (more rarely followed) by pumice fallout with limited dispersal, and someeruptions lack any associated pumice fall deposit, suggesting the absence of tall eruption columns. Particular attentionis given to the correlation of well-developed lithic breccias in the ignimbrites, interpreted as probabletracers of caldera collapses. They record as many as five caldera collapse events, in contrast to the two events reportedto date. Inter-ignimbrite periods are characterised by explosive and effusive eruptions with limited dispersal,such as small pumice cones, as well as pedogenesis. These periods have similar characteristics as thecurrent post-Green Tuff activity on the island, and, while not imminent, it is reasonable to postulate the occurrenceof another ignimbrite-forming eruption sometime in the future.© 2017 Elsevier B.V. All rights reserved.