Bulletin of Volcanology

, Volume 68, Issue 1, pp 21–36

Seismic activity related to the 2000 eruption of the Hekla volcano, Iceland

  • Heidi Soosalu
  • Páll Einarsson
  • Bergþóra S. Þorbjarnardóttir
Research Article

Abstract

The 2000 Hekla eruption took place from February 26 to March 8. Its seismic expressions were a swarm of numerous small earthquakes related to its onset, and low-frequency volcanic tremor that continued throughout the eruption. A swarm of small earthquakes was observed some 80 min before the onset of the eruption, and the size of the events increased with time. Low-frequency volcanic tremor, with a characteristic frequency band of 0.5–1.5 Hz and dominant spectral peak(s) at 0.7–0.9 Hz, became visible at 18:19 GMT on February 26, marking the onset of the eruption. The tremor amplitude rose quickly and was very high in the beginning of the eruption. However, it soon began to decrease after about an hour. In general, the seismic activity related to the 2000 Hekla eruption was very similar to what was observed in the previous eruption in 1991. Based on knowledge gained from seismicity and strain observations from 1991, this was the first time that a Hekla eruption was predicted.

Keywords

Hekla eruption 2000 Earthquakes Volcanic tremor Low-frequency earthquakes 

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Heidi Soosalu
    • 1
    • 4
  • Páll Einarsson
    • 2
  • Bergþóra S. Þorbjarnardóttir
    • 3
  1. 1.Nordic Volcanological Center, Institute of Earth SciencesUniversity of IcelandReykjavíkIceland
  2. 2.Institute of Earth SciencesUniversity of IcelandReykjavíkIceland
  3. 3.Icelandic Meteorological OfficeReykjavíkIceland
  4. 4.Present address: Department of Earth Sciences, Bullard LaboratoriesCambridge UniversityCambridgeUnited Kingdom

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