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

Abstract : 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 comprehensive stratigraphic reconstruction of the island. We find that the pre-46 ka succession is characterised by eight silica-rich peralkaline (trachyte to pantellerite) ignimbrites, many of which blanketed the entire island. The ignimbrites are typically welded to rheomorphic, and are often associated with lithic breccias and/or pumice deposits. They record sustained radial pyroclastic density currents fed by low pyroclastic fountains. The onset of ignimbrite emplacement is typically preceded (more rarely followed) by pumice fallout with limited dispersal, and some eruptions lack any associated pumice fall deposit, suggesting the absence of tall eruption columns. Particular attention is given to the correlation of well-developed lithic breccias in the ignimbrites, interpreted as probable tracers of caldera collapses. They record as many as five caldera collapse events, in contrast to the two events reported to 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 the current post-Green Tuff activity on the island, and, while not imminent, it is reasonable to postulate the occurrence of another ignimbrite-forming eruption sometime in the future.
Type de document :
Article dans une revue
Journal of Volcanology and Geothermal Research, Elsevier, 2018, 349, pp.47-73. 〈10.1016/j.jvolgeores.2017.09.013〉
Liste complète des métadonnées

Littérature citée [62 références]  Voir  Masquer  Télécharger

https://hal-insu.archives-ouvertes.fr/insu-01618160
Contributeur : Nathalie Pothier <>
Soumis le : mardi 17 octobre 2017 - 15:05:09
Dernière modification le : jeudi 11 janvier 2018 - 06:28:20
Document(s) archivé(s) le : jeudi 18 janvier 2018 - 15:00:54

Fichier

 Accès restreint
Fichier visible le : 2018-04-17

Connectez-vous pour demander l'accès au fichier

Identifiants

Collections

Citation

Nina Jordan, Silvio G. Rotolo, Rebecca Williams, Fabio Speranza, William Mcintosh, et al.. Explosive eruptive history of Pantelleria, Italy: Repeated caldera collapse and ignimbrite emplacement at a peralkaline volcano. Journal of Volcanology and Geothermal Research, Elsevier, 2018, 349, pp.47-73. 〈10.1016/j.jvolgeores.2017.09.013〉. 〈insu-01618160〉

Partager

Métriques

Consultations de la notice

58