Inflated pyroclasts in proximal fallout deposits reveal abrupt transitions in eruption behaviour - INSU - Institut national des sciences de l'Univers Accéder directement au contenu
Article Dans Une Revue Nature Communications Année : 2022

Inflated pyroclasts in proximal fallout deposits reveal abrupt transitions in eruption behaviour

Résumé

During explosive eruption of low viscosity magmas, pyroclasts are cooled predominantly by forced convection. Depending on the cooling efficiency relative to other timescales, a spectrum of deposits can be formed. Deposition of hot clasts, above their glass transition temperature, can form spatter mounds, ramparts and clastogenic lava flows. Clasts may also be deposited cold, producing tephra cones and blankets. Thus, the deposit and pyroclast type can provide information about eruption dynamics and magma properties. Here we examine pyroclasts from Tseax volcano, British Columbia, Canada. These newly identified inflated pyroclasts, are fluidal in form, have undergone post-depositional expansion, and are found juxtaposed with scoria. Detailed field, chemical and textural observations, coupled with high temperature rheometry and thermal modelling, reveal that abrupt transitions in eruptive behaviour — from lava fountaining to low-energy bubble bursts — created these pyroclastic deposits. These findings should help identify transitions in eruptive behaviour at other mafic volcanoes worldwide.
Fichier principal
Vignette du fichier
s41467-022-30501-6.pdf (4.4 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

insu-03825086 , version 1 (21-10-2022)

Licence

Paternité

Identifiants

Citer

Thomas J. Jones, Yannick Le Moigne, James K. Russell, Glyn Williams-Jones, Daniele Giordano, et al.. Inflated pyroclasts in proximal fallout deposits reveal abrupt transitions in eruption behaviour. Nature Communications, 2022, 13, 327, p. 53-78. ⟨10.1038/s41467-022-30501-6⟩. ⟨insu-03825086⟩
61 Consultations
30 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More