Publications des scientifiques de l'IRD

Castruccio A., Clavero J., Segura A., Samaniego Pablo, Roche Olivier, Le Pennec Jean-Luc, Droguett B. (2016). Eruptive parameters and dynamics of the April 2015 sub-Plinian eruptions of Calbuco volcano (southern Chile). Bulletin of Volcanology, 78 (9), p. art. 62 [19 p.]. ISSN 0258-8900.

Titre du document
Eruptive parameters and dynamics of the April 2015 sub-Plinian eruptions of Calbuco volcano (southern Chile)
Année de publication
2016
Type de document
Article référencé dans le Web of Science WOS:000383243700005
Auteurs
Castruccio A., Clavero J., Segura A., Samaniego Pablo, Roche Olivier, Le Pennec Jean-Luc, Droguett B.
Source
Bulletin of Volcanology, 2016, 78 (9), p. art. 62 [19 p.] ISSN 0258-8900
We conducted geological and petrological analyses of the tephra fallout and pyroclastic density current (PDC) products of the 22-23 April 2015 Calbuco eruptions. The eruptive cycle consisted of two sub-Plinian phases that generated > 15 km height columns and PDCs that travelled up to 6 km from the vent. The erupted volume is estimated at 0.38 km(3) (non-DRE), with approximately 90% corresponding to tephra fall deposits and the other 10% to PDC deposits. The erupted products are basaltic-andesite, 54-55 wt.% SiO2, with minor amounts of andesite (58 wt.% SiO2). Despite the uniform composition of the products, there are at least four types of textures in juvenile clasts, with different degrees of vesicularity and types and content of crystals. We propose that the eruption triggering mechanism was either exsolution of volatiles due to crystallization, or a small intrusion into the base of the magma chamber, without significant magma mixing or with a magma compositionally similar to that of the residing magma. In either case the triggering mechanism generated convection and sufficient overpressure to promote the first eruptive phase. The start of the eruption decompressed the chamber, promoting intense vesiculation of the remaining magma and an increase in eruption rate towards the end of the eruption.
Plan de classement
Géophysique interne [066]
Description Géographique
CHILI ; ANDES ; CALBUCO VOLCAN
Localisation
Fonds IRD [F B010068150]
Identifiant IRD
fdi:010068150
Contact