Bulletin of Volcanology

, Volume 72, Issue 5, pp 523–538

Rhyolites at Kerlingarfjöll, Iceland: the evolution and lifespan of silicic central volcanoes

  • Stephanie Flude
  • David W. McGarvie
  • Ray Burgess
  • Andrew G. Tindle
Research Article

DOI: 10.1007/s00445-010-0344-0

Cite this article as:
Flude, S., McGarvie, D.W., Burgess, R. et al. Bull Volcanol (2010) 72: 523. doi:10.1007/s00445-010-0344-0

Abstract

Kerlingarfjöll central volcano is Iceland’s second largest outcrop of Quaternary rhyolite and is part of the Icelandic Western Rift Zone. Geochemical and Ar/Ar age data show that at least 21 different rhyolite eruptions have taken place at Kerlingarfjöll over the last 350 ka. Ar/Ar dating was carried out on samples of obsidian which showed variable reproducibility, illustrating the difficulty in dating young Icelandic volcanics. Nevertheless, reasonable estimates of eruption age have been derived for a number of eruptive units that are consistent with observed stratigraphy, enabling an understanding of the temporal evolution of Kerlingarfjöll. Two rhyolite magma types are present. The first is an older, low-Nb rhyolite that was erupted episodically along a cryptic curved fracture system, to form a discontinuous ring of rhyolite mountains, between 350 and 250 ka. This discontinuous ring is similar to structures observed at other volcanoes in Iceland, suggesting that the development of a curved fracture that acts as a pathway for episodic silicic eruptions is a feature of central volcano development. The second magma is a younger, high-Nb rhyolite that was erupted episodically between 250 and 68 ka in the northern part of Kerlingarfjöll, forming two clusters, both of which have areas of intense hydrothermal activity. Repose periods for rhyolite volcanism are thought to be on the order of tens of thousands of years, and it is possible that Kerlingarfjöll will erupt rhyolite again in the future.

Keywords

IcelandRhyoliteCentral volcanoAr/Ar datingObsidianSubglacial volcanism

Supplementary material

445_2010_344_MOESM1_ESM.pdf (1.3 mb)
ESM1 (PDF 232 kb)

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Stephanie Flude
    • 1
    • 2
  • David W. McGarvie
    • 2
  • Ray Burgess
    • 1
  • Andrew G. Tindle
    • 2
  1. 1.The University of Manchester, Earth, Atmospheric and Environmental SciencesManchesterUK
  2. 2.The Open University, Earth and Environmental SciencesMilton KeynesUK