Insights into the 1976–2000 eruption episode of Whakaari/White Island, New Zealand: an eruption fuelled by repeated mafic recharge

Autor: Geoff Kilgour, Séverine Moune, Fernando Della Pasqua, Bruce Christenson
Přispěvatelé: Observatoire Volcanologique et Sismologique de Guadeloupe (OVSG), Institut de Physique du Globe de Paris, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), Institut de Physique du Globe de Paris (IPG Paris), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Bulletin of Volcanology
Bulletin of Volcanology, Springer Verlag, 2021, 83 (6), ⟨10.1007/s00445-021-01460-5⟩
Bulletin of Volcanology, 2021, 83 (6), ⟨10.1007/s00445-021-01460-5⟩
ISSN: 0258-8900
1432-0819
Popis: Whakaari is New Zealand’s most active volcano, and its last major magmatic eruption occurred during a protracted episode between 1976 and 2000. This eruption episode involved a sustained phase of heightened unrest, punctuated by regular, and small-volume, phreatic, magmatic and phreatomagmatic eruptions. We examine the scoria sample suite erupted throughout this period to develop a model for the storage conditions and the underlying cause of this long-lived activity. From our analysis of the major element composition of minerals, groundmass glass and phenocryst-hosted melt inclusions, along with the volatile content of melt inclusions, Whakaari magmas are relatively hot and dry arc andesites when compared globally. Based on a combination of plagioclase hygrometry, volatile contents of phenocryst-hosted melt inclusions and thermodynamic modelling, we conceptualize a distributed magmatic system that is dominated by andesite. We find that the 1976–2000 eruption episode was largely driven by volatile poor andesite-dacite magma that was periodically intruded by a relatively primitive mafic magma throughout this period. This andesite-dacite crustal magma reservoir (to at least 9 km) is capped by a shallow storage reservoir at ~1- to 2-km depth, where magmas stalled before erupting. Mafic magma/s periodically intruded the andesite-dacite reservoir providing heat, melt, volatiles, and mafic minerals, including olivine, into the system. Finally, we show that the volatile budget during this small-volume eruption episode released significant S and Cl into the atmosphere, similar in scale to large basaltic eruptions.
Databáze: OpenAIRE
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