Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes
We recorded high-frequency (> 10 Hz) harmonic tremor with spectral gliding at Hekla Volcano in Iceland. Particle motion plots indicated a shallow tremor source. We observed up to two overtones beneath our Nyquist frequency of 50 Hz and could resolve a source of closely spaced pulses of very short...
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ftunivcolldublin:oai:researchrepository.ucd.ie:10197/7005 2023-05-15T16:34:02+02:00 Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes Eibl, Eva P. S. Lokmer, Ivan Bean, Christopher J. 2015-09-10T10:13:15Z http://hdl.handle.net/10197/7005 https://doi.org/10.1016/j.jvolgeores.2015.08.002 en eng Elsevier Journal of Volcanology and Geothermal Research http://hdl.handle.net/10197/7005 304 108 117 doi:10.1016/j.jvolgeores.2015.08.002 This is the author’s version of a work that was accepted for publication in Journal of Volcanology and Geothermal Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Volcanology and Geothermal Research (VOL 304, ISSUE 2015, (2015)) DOI:10.1016/j.jvolgeores.2015.08.002 Frequency gliding Doppler shift Harmonic tremor Helicopter Volcano Journal Article 2015 ftunivcolldublin https://doi.org/10.1016/j.jvolgeores.2015.08.002 2022-04-08T14:18:40Z We recorded high-frequency (> 10 Hz) harmonic tremor with spectral gliding at Hekla Volcano in Iceland. Particle motion plots indicated a shallow tremor source. We observed up to two overtones beneath our Nyquist frequency of 50 Hz and could resolve a source of closely spaced pulses of very short duration (0.03-0.1 s) on zoomed seismograms. Volcanic tremor with fundamental frequencies above 5 Hz, frequency gliding and/or repetitive sources similar to our observations were observed on different volcanoes around the world. However, this frequency content, duration and occurrence of volcano-related tremor was not observed in the last 35 years of seismic observations at Hekla. Detailed analysis reveals that this tremor was related to helicopters passing the volcano. This study relates the GPS track of a helicopter with seismic recordings of the helicopter at various distances. We show the effect the distance, number of rotor blades and velocity of the helicopter has on the observed up and down glidings at up to 40 km distance. We highlight similarities and differences between volcano-related and helicopter tremor in order to help avoid misinterpretations. European Commission - Seventh Framework Programme (FP7) Article in Journal/Newspaper Hekla Iceland University College Dublin: Research Repository UCD Journal of Volcanology and Geothermal Research 304 108 117 |
institution |
Open Polar |
collection |
University College Dublin: Research Repository UCD |
op_collection_id |
ftunivcolldublin |
language |
English |
topic |
Frequency gliding Doppler shift Harmonic tremor Helicopter Volcano |
spellingShingle |
Frequency gliding Doppler shift Harmonic tremor Helicopter Volcano Eibl, Eva P. S. Lokmer, Ivan Bean, Christopher J. Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
topic_facet |
Frequency gliding Doppler shift Harmonic tremor Helicopter Volcano |
description |
We recorded high-frequency (> 10 Hz) harmonic tremor with spectral gliding at Hekla Volcano in Iceland. Particle motion plots indicated a shallow tremor source. We observed up to two overtones beneath our Nyquist frequency of 50 Hz and could resolve a source of closely spaced pulses of very short duration (0.03-0.1 s) on zoomed seismograms. Volcanic tremor with fundamental frequencies above 5 Hz, frequency gliding and/or repetitive sources similar to our observations were observed on different volcanoes around the world. However, this frequency content, duration and occurrence of volcano-related tremor was not observed in the last 35 years of seismic observations at Hekla. Detailed analysis reveals that this tremor was related to helicopters passing the volcano. This study relates the GPS track of a helicopter with seismic recordings of the helicopter at various distances. We show the effect the distance, number of rotor blades and velocity of the helicopter has on the observed up and down glidings at up to 40 km distance. We highlight similarities and differences between volcano-related and helicopter tremor in order to help avoid misinterpretations. European Commission - Seventh Framework Programme (FP7) |
format |
Article in Journal/Newspaper |
author |
Eibl, Eva P. S. Lokmer, Ivan Bean, Christopher J. |
author_facet |
Eibl, Eva P. S. Lokmer, Ivan Bean, Christopher J. |
author_sort |
Eibl, Eva P. S. |
title |
Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
title_short |
Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
title_full |
Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
title_fullStr |
Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
title_full_unstemmed |
Helicopter vs. volcanic tremor: Characteristic features of seismic harmonic tremor on volcanoes |
title_sort |
helicopter vs. volcanic tremor: characteristic features of seismic harmonic tremor on volcanoes |
publisher |
Elsevier |
publishDate |
2015 |
url |
http://hdl.handle.net/10197/7005 https://doi.org/10.1016/j.jvolgeores.2015.08.002 |
genre |
Hekla Iceland |
genre_facet |
Hekla Iceland |
op_relation |
Journal of Volcanology and Geothermal Research http://hdl.handle.net/10197/7005 304 108 117 doi:10.1016/j.jvolgeores.2015.08.002 |
op_rights |
This is the author’s version of a work that was accepted for publication in Journal of Volcanology and Geothermal Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Volcanology and Geothermal Research (VOL 304, ISSUE 2015, (2015)) DOI:10.1016/j.jvolgeores.2015.08.002 |
op_doi |
https://doi.org/10.1016/j.jvolgeores.2015.08.002 |
container_title |
Journal of Volcanology and Geothermal Research |
container_volume |
304 |
container_start_page |
108 |
op_container_end_page |
117 |
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1766023781181030400 |