Magma plumbing for the 2014–2015 Holuhraun eruption, Iceland
2016 (English)In: Geochemistry Geophysics Geosystems, ISSN 1525-2027, E-ISSN 1525-2027, Vol. 17Article in journal (Refereed) Published
The 2014–2015 Holuhraun eruption on Iceland was located within the Askja fissure swarm butwas accompanied by caldera subsidence in the Barðarbunga central volcano 45 km to the southwest. Geophysicalmonitoring of the eruption identified a seismic swarm that migrated from Barðarbunga to theHoluhraun eruption site over the course of two weeks. In order to better understand this lateral connectionbetween Barðarbunga and Holuhraun, we present mineral textures and compositions, mineral-meltequilibriumcalculations, whole rock and trace element data, and oxygen isotope ratios for selected Holuhraunsamples. The Holuhraun lavas are compositionally similar to recorded historical eruptions from theBarðarbunga volcanic system but are distinct from the historical eruption products of the nearby Askja system.Thermobarometry calculations indicate a polybaric magma plumbing system for the Holuhraun eruption,wherein clinopyroxene and plagioclase crystallized at average depths of 17 km and 5 km,respectively. Crystal resorption textures and oxygen isotope variations imply that this multilevel plumbingsystem facilitated magma mixing and assimilation of low-d18O Icelandic crust prior to eruption. In conjunctionwith the existing geophysical evidence for lateral migration, our results support a model of initial verticalmagma ascent within the Barðarbunga plumbing system followed by lateral transport of aggregatedmagma batches within the upper crust to the Holuhraun eruption site.
Place, publisher, year, edition, pages
2016. Vol. 17
Research subject Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics
IdentifiersURN: urn:nbn:se:uu:diva-304630DOI: 10.1002/2016GC006317OAI: oai:DiVA.org:uu-304630DiVA: diva2:1033317