Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska
Detection of the earliest stages of unrest is one of the most challenging and yet critically needed aspects of volcano monitoring. We investigate a sequence of five unusual long-period (LP) earthquakes that occurred in the days prior to the onset of a months-long volcano-tectonic (VT) earthquake swa...
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Online Access: | http://dx.doi.org/10.3389/feart.2021.689651 https://www.frontiersin.org/articles/10.3389/feart.2021.689651/full |
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crfrontiers:10.3389/feart.2021.689651 2024-02-11T10:09:28+01:00 Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska Haney, Matthew M. Buurman, Helena Holtkamp, Stephen McNutt, Stephen R. 2021 http://dx.doi.org/10.3389/feart.2021.689651 https://www.frontiersin.org/articles/10.3389/feart.2021.689651/full unknown Frontiers Media SA https://creativecommons.org/licenses/by/4.0/ Frontiers in Earth Science volume 9 ISSN 2296-6463 General Earth and Planetary Sciences journal-article 2021 crfrontiers https://doi.org/10.3389/feart.2021.689651 2024-01-26T10:02:56Z Detection of the earliest stages of unrest is one of the most challenging and yet critically needed aspects of volcano monitoring. We investigate a sequence of five unusual long-period (LP) earthquakes that occurred in the days prior to the onset of a months-long volcano-tectonic (VT) earthquake swarm beneath Little Sitkin volcano in the Aleutian Islands during late 2012. The long-period earthquakes had two distinctive characteristics: their signals were dominated by a monochromatic spectral peak at approximately 0.57 Hz and they had impulsive P and S-wave arrivals on a seismometer located on Amchitka Island 80 km to the southeast of the volcano. In each case, the monochromatic earthquakes ended with a higher-frequency event after approximately 2 min of duration. We find evidence that the five monochromatic LP earthquakes resulted from the resonance of a tabular magma body at middle crustal depths (15 km) on the western side of Little Sitkin. Based on the resonant frequency and quality factor of the monochromatic LP earthquakes, we infer the magma body to have a lateral extent of 500 m and a thickness of 9 m. We interpret that a magmatic intrusion excited the monochromatic LP earthquakes and subsequently increased the stress beneath the volcano, leading to the onset of the shallow (<10 km depth) VT swarm five days later. Article in Journal/Newspaper Alaska Aleutian Islands Frontiers (Publisher) Amchitka ENVELOPE(178.878,178.878,51.567,51.567) Amchitka Island ENVELOPE(178.983,178.983,51.542,51.542) Journal of Asian Earth Sciences 36 6 420 433 |
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Open Polar |
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Frontiers (Publisher) |
op_collection_id |
crfrontiers |
language |
unknown |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Haney, Matthew M. Buurman, Helena Holtkamp, Stephen McNutt, Stephen R. Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
topic_facet |
General Earth and Planetary Sciences |
description |
Detection of the earliest stages of unrest is one of the most challenging and yet critically needed aspects of volcano monitoring. We investigate a sequence of five unusual long-period (LP) earthquakes that occurred in the days prior to the onset of a months-long volcano-tectonic (VT) earthquake swarm beneath Little Sitkin volcano in the Aleutian Islands during late 2012. The long-period earthquakes had two distinctive characteristics: their signals were dominated by a monochromatic spectral peak at approximately 0.57 Hz and they had impulsive P and S-wave arrivals on a seismometer located on Amchitka Island 80 km to the southeast of the volcano. In each case, the monochromatic earthquakes ended with a higher-frequency event after approximately 2 min of duration. We find evidence that the five monochromatic LP earthquakes resulted from the resonance of a tabular magma body at middle crustal depths (15 km) on the western side of Little Sitkin. Based on the resonant frequency and quality factor of the monochromatic LP earthquakes, we infer the magma body to have a lateral extent of 500 m and a thickness of 9 m. We interpret that a magmatic intrusion excited the monochromatic LP earthquakes and subsequently increased the stress beneath the volcano, leading to the onset of the shallow (<10 km depth) VT swarm five days later. |
format |
Article in Journal/Newspaper |
author |
Haney, Matthew M. Buurman, Helena Holtkamp, Stephen McNutt, Stephen R. |
author_facet |
Haney, Matthew M. Buurman, Helena Holtkamp, Stephen McNutt, Stephen R. |
author_sort |
Haney, Matthew M. |
title |
Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
title_short |
Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
title_full |
Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
title_fullStr |
Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
title_full_unstemmed |
Monochromatic Long-Period Seismicity Prior to the 2012 Earthquake Swarm at Little Sitkin Volcano, Alaska |
title_sort |
monochromatic long-period seismicity prior to the 2012 earthquake swarm at little sitkin volcano, alaska |
publisher |
Frontiers Media SA |
publishDate |
2021 |
url |
http://dx.doi.org/10.3389/feart.2021.689651 https://www.frontiersin.org/articles/10.3389/feart.2021.689651/full |
long_lat |
ENVELOPE(178.878,178.878,51.567,51.567) ENVELOPE(178.983,178.983,51.542,51.542) |
geographic |
Amchitka Amchitka Island |
geographic_facet |
Amchitka Amchitka Island |
genre |
Alaska Aleutian Islands |
genre_facet |
Alaska Aleutian Islands |
op_source |
Frontiers in Earth Science volume 9 ISSN 2296-6463 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3389/feart.2021.689651 |
container_title |
Journal of Asian Earth Sciences |
container_volume |
36 |
container_issue |
6 |
container_start_page |
420 |
op_container_end_page |
433 |
_version_ |
1790609390376583168 |