TY - JOUR
T1 - Delimiting Bárðarbunga and Askja volcanic systems with Sr-and Nd-isotope ratios
AU - Sigmarsson, Olgeir
AU - Halldórsson, Sæmundur Ari
N1 - Funding Information: We thank our colleagues, including several post-docs and graduate students at IES that aided with sample collection during the 2014–2015 Holuhraun eruption. Chantal Bosq and Delphine Auclair helped with the Sr and Nd isotope analysis. Guðrún Larsen read over first draft of the manuscript. Rósa Ólafsdóttir prepared Figure 1. Margaret Hartley, Thomas F. Kok-felt and Bryndís Brandsdóttir provided constructive reviews and comments. All this is gratefully acknowledged. SAH is especially grateful to Guðrún Sverris-dóttir and Gylfi Sigurðsson for their hard work and dedication to the isotope facilities at IES. Financial support came from the Iceland Science Fund through the project "Volcano Anatomy" and the Nordic Volcanological Centre (Nordvulk) at IES. Publisher Copyright: © 2015, Iceland Glaciological Society. All rights reserved.
PY - 2015
Y1 - 2015
N2 - — Volcanic systems represent a fundamental component of the neovolcanic zones in Iceland. They are composed of a central volcano and a fissure swarm, or a combination of the two. The 2014–2015 rifting event at the Bárðarbunga volcanic system produced basaltic lava approximately 40 km to the north of the central volcano, within a fissure swarm commonly attributed to the Askja volcanic system, highlighting the complex tectonic structure of a region, directly above the Iceland mantle plume. New analyses of Sr-and Nd-isotope ratios from the new lava (Holuhraun), and the underlying older Holuhraun lava, show that they have identical values to those of the Bárðarbunga-Veiðivötn lavas and tephra erupted during the Holocene. Moreover, comparison with published high-precision radiogenic isotope data, reveals that Holocene lavas and tephra from the Bárðarbunga and Askja systems are characterized by contrasting Sr-and Nd-isotope ratios, with the notable exception of the Þjórsárhraun lava and two early Holocene lavas from the extreme west and east of the Veiðivötn fissure swarm. The87 Sr/86 Sr and143 Nd/144 Nd isotope ratios can thus be utilized to define the provenance of lava flows north of the Vatnajökull ice cap, ascertaining that the large lava fields of Krepputunguhraun and Fjallsendahraun (Frambruni) must also have originated within the Bárðarbunga volcanic system.
AB - — Volcanic systems represent a fundamental component of the neovolcanic zones in Iceland. They are composed of a central volcano and a fissure swarm, or a combination of the two. The 2014–2015 rifting event at the Bárðarbunga volcanic system produced basaltic lava approximately 40 km to the north of the central volcano, within a fissure swarm commonly attributed to the Askja volcanic system, highlighting the complex tectonic structure of a region, directly above the Iceland mantle plume. New analyses of Sr-and Nd-isotope ratios from the new lava (Holuhraun), and the underlying older Holuhraun lava, show that they have identical values to those of the Bárðarbunga-Veiðivötn lavas and tephra erupted during the Holocene. Moreover, comparison with published high-precision radiogenic isotope data, reveals that Holocene lavas and tephra from the Bárðarbunga and Askja systems are characterized by contrasting Sr-and Nd-isotope ratios, with the notable exception of the Þjórsárhraun lava and two early Holocene lavas from the extreme west and east of the Veiðivötn fissure swarm. The87 Sr/86 Sr and143 Nd/144 Nd isotope ratios can thus be utilized to define the provenance of lava flows north of the Vatnajökull ice cap, ascertaining that the large lava fields of Krepputunguhraun and Fjallsendahraun (Frambruni) must also have originated within the Bárðarbunga volcanic system.
UR - https://www.scopus.com/pages/publications/85013746006
M3 - Article
SN - 0449-0576
SP - 17
EP - 27
JO - Jokull
JF - Jokull
IS - 65
ER -