The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography
The magmatic plumbing system beneath Askja, a volcano in the central Icelandic highlands, is imaged using local earthquake tomography. We use a catalog of more than 1300 earthquakes widely distributed in location and depth to invert for the $P$ wave velocity ($V_p$) and the $V_p$/$V_s$ ratio. Extens...
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ftunivcam:oai:www.repository.cam.ac.uk:1810/261235 2024-02-04T10:01:36+01:00 The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography Greenfield, T White, RS Roecker, S 2016-11-11 application/pdf https://www.repository.cam.ac.uk/handle/1810/261235 https://doi.org/10.17863/CAM.6406 eng eng Wiley http://dx.doi.org/10.1002/2016jb013163 Journal of Geophysical Research: Solid Earth https://www.repository.cam.ac.uk/handle/1810/261235 doi:10.17863/CAM.6406 Attribution-NonCommercial 4.0 International http://creativecommons.org/licenses/by-nc/4.0/ 37 Earth Sciences 3703 Geochemistry 3705 Geology 3706 Geophysics Article 2016 ftunivcam https://doi.org/10.17863/CAM.6406 2024-01-11T23:19:29Z The magmatic plumbing system beneath Askja, a volcano in the central Icelandic highlands, is imaged using local earthquake tomography. We use a catalog of more than 1300 earthquakes widely distributed in location and depth to invert for the $P$ wave velocity ($V_p$) and the $V_p$/$V_s$ ratio. Extensive synthetic tests show that the minimum size of any velocity anomaly recovered by the model is ~4 km in the upper crust (depth < 8 km below sea level (bsl)), increasing to ~10 km in the lower crust at a depth of 20 km bsl. The plumbing system of Askja is revealed as a series of high-$V_p$/$V_s$ ratio bodies situated at discrete depths throughout the crust to depths of over 20 km. We interpret these to be regions of the crust which currently store melt with melt fractions of ~10%. The lower crustal bodies are all seismically active, suggesting that melt is being actively transported in these regions. The main melt storage regions lie beneath Askja volcano, concentrated at depths of 5 km bsl with a smaller region at 9 km bsl. Their total volume is ~100 km$^3$. Using the recorded waveforms, we show that there is also likely to be a small, highly attenuating magmatic body at a shallower depth of about 2 km bsl. Seismometers were provided by the Natural Environment Research Council SEIS-UK under loans 968 and 1022, and the Icelandic Meteorological Office kindly provided data from the seismometers which they operate around Askja. Funding was provided to T.G. from a Shell UK studentship and to R.S.W. by a Natural Environment Research Council grant NE/H025006/1. T.G. and R.S.W. would also like to acknowledge funding from the European Community’s Seventh Framework Programme grant 308377 (Project FUTUREVOLC). Article in Journal/Newspaper Iceland Apollo - University of Cambridge Repository Askja ENVELOPE(-16.802,-16.802,65.042,65.042) |
institution |
Open Polar |
collection |
Apollo - University of Cambridge Repository |
op_collection_id |
ftunivcam |
language |
English |
topic |
37 Earth Sciences 3703 Geochemistry 3705 Geology 3706 Geophysics |
spellingShingle |
37 Earth Sciences 3703 Geochemistry 3705 Geology 3706 Geophysics Greenfield, T White, RS Roecker, S The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
topic_facet |
37 Earth Sciences 3703 Geochemistry 3705 Geology 3706 Geophysics |
description |
The magmatic plumbing system beneath Askja, a volcano in the central Icelandic highlands, is imaged using local earthquake tomography. We use a catalog of more than 1300 earthquakes widely distributed in location and depth to invert for the $P$ wave velocity ($V_p$) and the $V_p$/$V_s$ ratio. Extensive synthetic tests show that the minimum size of any velocity anomaly recovered by the model is ~4 km in the upper crust (depth < 8 km below sea level (bsl)), increasing to ~10 km in the lower crust at a depth of 20 km bsl. The plumbing system of Askja is revealed as a series of high-$V_p$/$V_s$ ratio bodies situated at discrete depths throughout the crust to depths of over 20 km. We interpret these to be regions of the crust which currently store melt with melt fractions of ~10%. The lower crustal bodies are all seismically active, suggesting that melt is being actively transported in these regions. The main melt storage regions lie beneath Askja volcano, concentrated at depths of 5 km bsl with a smaller region at 9 km bsl. Their total volume is ~100 km$^3$. Using the recorded waveforms, we show that there is also likely to be a small, highly attenuating magmatic body at a shallower depth of about 2 km bsl. Seismometers were provided by the Natural Environment Research Council SEIS-UK under loans 968 and 1022, and the Icelandic Meteorological Office kindly provided data from the seismometers which they operate around Askja. Funding was provided to T.G. from a Shell UK studentship and to R.S.W. by a Natural Environment Research Council grant NE/H025006/1. T.G. and R.S.W. would also like to acknowledge funding from the European Community’s Seventh Framework Programme grant 308377 (Project FUTUREVOLC). |
format |
Article in Journal/Newspaper |
author |
Greenfield, T White, RS Roecker, S |
author_facet |
Greenfield, T White, RS Roecker, S |
author_sort |
Greenfield, T |
title |
The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
title_short |
The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
title_full |
The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
title_fullStr |
The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
title_full_unstemmed |
The magmatic plumbing system of the Askja central volcano, Iceland, as imaged by seismic tomography |
title_sort |
magmatic plumbing system of the askja central volcano, iceland, as imaged by seismic tomography |
publisher |
Wiley |
publishDate |
2016 |
url |
https://www.repository.cam.ac.uk/handle/1810/261235 https://doi.org/10.17863/CAM.6406 |
long_lat |
ENVELOPE(-16.802,-16.802,65.042,65.042) |
geographic |
Askja |
geographic_facet |
Askja |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
https://www.repository.cam.ac.uk/handle/1810/261235 doi:10.17863/CAM.6406 |
op_rights |
Attribution-NonCommercial 4.0 International http://creativecommons.org/licenses/by-nc/4.0/ |
op_doi |
https://doi.org/10.17863/CAM.6406 |
_version_ |
1789967607828316160 |