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| Titel |
Dyke propagation mechanisms and the immediate pre- and syn-eruptive seismicity of the 2014 Holuhraun fissure eruption, Iceland |
| VerfasserIn |
Jennifer Woods, Thorbjörg Ágústsdóttir, Tim Greenfield, Robert G. Green, Robert S. White, Bryndís Brandsdóttir, Sveinbjörn Steinthórsson, Simon Redfern |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250110425
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| Publikation (Nr.) |
 EGU/EGU2015-10420.pdf |
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| Zusammenfassung |
| We present data from our dense seismic array which captured the micro-seismicity associated
with the propagating dyke intrusion from the subglacial Bárðarbunga volcano,
during the 24 hours preceding and following the onset of effusive magmatism at the
Holuhraun lava field in central Iceland. The Bárðarbunga volcano is located at the centre
of the Iceland hot spot within the Eastern Rift Zone, beneath the Vatnajökull ice
cap.
Local magmatic intrusions can be tracked through the swarms of micro-seismicity
accompanying dyke propagation, arising from crustal failure and fracture of both the country
rock and solidifying magma plugs. August 2014 saw the beginning of a period of unrest of
Bárðarbunga volcano during which a dyke propagated first out of the caldera and then
towards the northeast. It continued north of the Dyngjujökull outlet glacier and resulted in a
fissure eruption in the old Holuhraun lava field on 29 August 2014. At time of writing it has
erupted ~1km3 of lava covering over 64km2, making this the largest eruption in Iceland for
150 years.
Our extensive, local seismic network covers the numerous volcanic systems beneath the
Vatnajökull glacier and their transecting fissure swarms (rifting units) along the divergent
plate boundary. This work focusses on the immediate pre- and syn-eruptive seismicity of the
2014 Holuhraun fissure eruption. Rock fracture mechanisms are determined from fault plane
solutions of these seismic events, produced as the magma migrated from beneath the surface
to the eruption site. |
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