The collapse of Bárðarbunga Caldera, Iceland

Lying below Vatnajökull ice cap in Iceland, Bárðarbunga stratovolcano began experiencing wholesale caldera collapse in 2014 August 16, one of the largest such events recorded in the modern instrumental era. Simultaneous with this collapse is the initiation of a plate boundary rifting episode north o...

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Bibliographic Details
Published in:Geophysical Journal International
Main Authors: Riel, B., Milillo, P., Simons, M., Lundgren, P., Kanamori, H., Samsonov, S.
Format: Article in Journal/Newspaper
Language:English
Published: Royal Astronomical Society 2015
Subjects:
Online Access:https://authors.library.caltech.edu/57840/
https://authors.library.caltech.edu/57840/1/Geophys.%20J.%20Int.-2015-Riel-446-53.pdf
https://authors.library.caltech.edu/57840/2/supp_Bardarbunga_GJI.pdf
https://resolver.caltech.edu/CaltechAUTHORS:20150527-065601451
Description
Summary:Lying below Vatnajökull ice cap in Iceland, Bárðarbunga stratovolcano began experiencing wholesale caldera collapse in 2014 August 16, one of the largest such events recorded in the modern instrumental era. Simultaneous with this collapse is the initiation of a plate boundary rifting episode north of the caldera. Observations using the international constellation of radar satellites indicate rapid 50 cm d^(−1) subsidence of the glacier surface overlying the collapsing caldera and metre-scale crustal deformation in the active rift zone. Anomalous earthquakes around the rim of the caldera with highly nondouble-couple focal mechanisms provide a mechanical link to the dynamics of the collapsing magma chamber. A model of the collapse consistent with available geodetic and seismic observations suggests that the majority of the observed subsidence occurs aseismically via a deflating sill-like magma chamber.