Ambient high-frequency seismic surface waves in the firn column of central west Antarctica
Firn is the pervasive surface material across Antarctica, and its structures reflect its formation and history in response to environmental perturbations. In addition to the role of firn in thermally isolating underlying glacial ice, it defines near-surface elastic and density structure and strongly...
Published in: | Journal of Glaciology |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press
2022
|
Subjects: | |
Online Access: | https://doi.org/10.1017/jog.2021.135 https://doaj.org/article/66f8d7babb874f8c9d49f7ad9ad5d329 |
id |
ftdoajarticles:oai:doaj.org/article:66f8d7babb874f8c9d49f7ad9ad5d329 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:66f8d7babb874f8c9d49f7ad9ad5d329 2023-05-15T13:36:52+02:00 Ambient high-frequency seismic surface waves in the firn column of central west Antarctica Julien Chaput Rick Aster Marianne Karplus Nori Nakata 2022-08-01T00:00:00Z https://doi.org/10.1017/jog.2021.135 https://doaj.org/article/66f8d7babb874f8c9d49f7ad9ad5d329 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143021001350/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.135 0022-1430 1727-5652 https://doaj.org/article/66f8d7babb874f8c9d49f7ad9ad5d329 Journal of Glaciology, Vol 68, Pp 785-798 (2022) Antarctic glaciology polar firn seismology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2022 ftdoajarticles https://doi.org/10.1017/jog.2021.135 2023-03-12T01:30:54Z Firn is the pervasive surface material across Antarctica, and its structures reflect its formation and history in response to environmental perturbations. In addition to the role of firn in thermally isolating underlying glacial ice, it defines near-surface elastic and density structure and strongly influences high-frequency (> 5 Hz) seismic phenomena observed near the surface. We investigate high-frequency seismic data collected with an array of seismographs deployed on the West Antarctic Ice Sheet (WAIS) near WAIS Divide camp in January 2019. Cross-correlations of anthropogenic noise originating from the approximately 5 km-distant camp were constructed using a 1 km-diameter circular array of 22 seismographs. We distinguish three Rayleigh (elastic surface) wave modes at frequencies up to 50 Hz that exhibit systematic spatially varying particle motion characteristics. The horizontal-to-vertical ratio for the second mode shows a spatial pattern of peak frequencies that matches particle motion transitions for both the fundamental and second Rayleigh modes. This pattern is further evident in the appearance of narrow band spectral peaks. We find that shallow lateral structural variations are consistent with these observations, and model spectral peaks as Rayleigh wave amplifications within similarly scaled shallow basin-like structures delineated by the strong velocity and density gradients typical of Antarctic firn. Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice Sheet Journal of Glaciology West Antarctica Directory of Open Access Journals: DOAJ Articles Antarctic West Antarctica West Antarctic Ice Sheet Journal of Glaciology 68 270 785 798 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Antarctic glaciology polar firn seismology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Antarctic glaciology polar firn seismology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Julien Chaput Rick Aster Marianne Karplus Nori Nakata Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
topic_facet |
Antarctic glaciology polar firn seismology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Firn is the pervasive surface material across Antarctica, and its structures reflect its formation and history in response to environmental perturbations. In addition to the role of firn in thermally isolating underlying glacial ice, it defines near-surface elastic and density structure and strongly influences high-frequency (> 5 Hz) seismic phenomena observed near the surface. We investigate high-frequency seismic data collected with an array of seismographs deployed on the West Antarctic Ice Sheet (WAIS) near WAIS Divide camp in January 2019. Cross-correlations of anthropogenic noise originating from the approximately 5 km-distant camp were constructed using a 1 km-diameter circular array of 22 seismographs. We distinguish three Rayleigh (elastic surface) wave modes at frequencies up to 50 Hz that exhibit systematic spatially varying particle motion characteristics. The horizontal-to-vertical ratio for the second mode shows a spatial pattern of peak frequencies that matches particle motion transitions for both the fundamental and second Rayleigh modes. This pattern is further evident in the appearance of narrow band spectral peaks. We find that shallow lateral structural variations are consistent with these observations, and model spectral peaks as Rayleigh wave amplifications within similarly scaled shallow basin-like structures delineated by the strong velocity and density gradients typical of Antarctic firn. |
format |
Article in Journal/Newspaper |
author |
Julien Chaput Rick Aster Marianne Karplus Nori Nakata |
author_facet |
Julien Chaput Rick Aster Marianne Karplus Nori Nakata |
author_sort |
Julien Chaput |
title |
Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
title_short |
Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
title_full |
Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
title_fullStr |
Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
title_full_unstemmed |
Ambient high-frequency seismic surface waves in the firn column of central west Antarctica |
title_sort |
ambient high-frequency seismic surface waves in the firn column of central west antarctica |
publisher |
Cambridge University Press |
publishDate |
2022 |
url |
https://doi.org/10.1017/jog.2021.135 https://doaj.org/article/66f8d7babb874f8c9d49f7ad9ad5d329 |
geographic |
Antarctic West Antarctica West Antarctic Ice Sheet |
geographic_facet |
Antarctic West Antarctica West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Antarctica Ice Sheet Journal of Glaciology West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Journal of Glaciology West Antarctica |
op_source |
Journal of Glaciology, Vol 68, Pp 785-798 (2022) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143021001350/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.135 0022-1430 1727-5652 https://doaj.org/article/66f8d7babb874f8c9d49f7ad9ad5d329 |
op_doi |
https://doi.org/10.1017/jog.2021.135 |
container_title |
Journal of Glaciology |
container_volume |
68 |
container_issue |
270 |
container_start_page |
785 |
op_container_end_page |
798 |
_version_ |
1766085153110622208 |