Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS
The detectability of low magnitude seismic events in the European Arctic is determined primarily by the small-aperture International Monitoring System arrays ARCES and SPITS. In August 2004, the SPITS array was upgraded to a broadband array with an increase in the sampling rate from 40 to 80 Hz. Mos...
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ftdatacite:10.17605/osf.io/f6qpz 2023-05-15T15:00:40+02:00 Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS Gibbons, Steven Schweitzer, Johannes Ringdal, Frode Kværna, Tormod Mykkeltveit, Svein Paulsen, Berit 2017 https://dx.doi.org/10.17605/osf.io/f6qpz https://doi.org/10.31223/osf.io/f6qpz unknown EarthArXiv https://dx.doi.org/10.1785/0120110109 Academic Free License (AFL) 3.0 Geophysics and Seismology Earth Sciences Physical Sciences and Mathematics Preprint Text article-journal ScholarlyArticle 2017 ftdatacite https://doi.org/10.17605/osf.io/f6qpz 2021-11-05T12:55:41Z The detectability of low magnitude seismic events in the European Arctic is determined primarily by the small-aperture International Monitoring System arrays ARCES and SPITS. In August 2004, the SPITS array was upgraded to a broadband array with an increase in the sampling rate from 40 to 80 Hz. Most important, however, for the detection and location of small-magnitude seismic events was the deployment of three-component instruments at six of the nine sites. Detection and correct classification of secondary phases are of paramount importance for events observed by only a small number of stations at regional distances; and, in the absence of the strong Lg phases typically observed for continental propagation paths, multiple three-component stations were deemed necessary to exploit the higher S-phase amplitudes anticipated on the horizontal sensors. We demonstrate improved signal-to-noise ratios (SNRs) for S phases on horizontal beams for several events close to Novaya Zemlya. Horizontal component f-k analysis improves direction estimates and phase classification for low-SNR signals. We demonstrate secondary phases that are misidentified by vertical-only f-k analysis but which are correctly classified by three-component array processing. A significant problem with array processing at SPITS is the overlap in slowness space of regional P and S phases. Phase identification is improved greatly by comparing the coherence between vertical traces with the coherence between horizontal traces. Considerations in the routine array processing of SPITS data are reviewed, including the need for elevation corrections in slowness estimation and the need to take into account azimuth-dependent variation of apparent velocity estimates for regional phases. Report Arctic Novaya Zemlya DataCite Metadata Store (German National Library of Science and Technology) Arctic |
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DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
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topic |
Geophysics and Seismology Earth Sciences Physical Sciences and Mathematics |
spellingShingle |
Geophysics and Seismology Earth Sciences Physical Sciences and Mathematics Gibbons, Steven Schweitzer, Johannes Ringdal, Frode Kværna, Tormod Mykkeltveit, Svein Paulsen, Berit Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
topic_facet |
Geophysics and Seismology Earth Sciences Physical Sciences and Mathematics |
description |
The detectability of low magnitude seismic events in the European Arctic is determined primarily by the small-aperture International Monitoring System arrays ARCES and SPITS. In August 2004, the SPITS array was upgraded to a broadband array with an increase in the sampling rate from 40 to 80 Hz. Most important, however, for the detection and location of small-magnitude seismic events was the deployment of three-component instruments at six of the nine sites. Detection and correct classification of secondary phases are of paramount importance for events observed by only a small number of stations at regional distances; and, in the absence of the strong Lg phases typically observed for continental propagation paths, multiple three-component stations were deemed necessary to exploit the higher S-phase amplitudes anticipated on the horizontal sensors. We demonstrate improved signal-to-noise ratios (SNRs) for S phases on horizontal beams for several events close to Novaya Zemlya. Horizontal component f-k analysis improves direction estimates and phase classification for low-SNR signals. We demonstrate secondary phases that are misidentified by vertical-only f-k analysis but which are correctly classified by three-component array processing. A significant problem with array processing at SPITS is the overlap in slowness space of regional P and S phases. Phase identification is improved greatly by comparing the coherence between vertical traces with the coherence between horizontal traces. Considerations in the routine array processing of SPITS data are reviewed, including the need for elevation corrections in slowness estimation and the need to take into account azimuth-dependent variation of apparent velocity estimates for regional phases. |
format |
Report |
author |
Gibbons, Steven Schweitzer, Johannes Ringdal, Frode Kværna, Tormod Mykkeltveit, Svein Paulsen, Berit |
author_facet |
Gibbons, Steven Schweitzer, Johannes Ringdal, Frode Kværna, Tormod Mykkeltveit, Svein Paulsen, Berit |
author_sort |
Gibbons, Steven |
title |
Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
title_short |
Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
title_full |
Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
title_fullStr |
Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
title_full_unstemmed |
Improvements to Seismic Monitoring of the European Arctic Using Three-Component Array Processing at SPITS |
title_sort |
improvements to seismic monitoring of the european arctic using three-component array processing at spits |
publisher |
EarthArXiv |
publishDate |
2017 |
url |
https://dx.doi.org/10.17605/osf.io/f6qpz https://doi.org/10.31223/osf.io/f6qpz |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Novaya Zemlya |
genre_facet |
Arctic Novaya Zemlya |
op_relation |
https://dx.doi.org/10.1785/0120110109 |
op_rights |
Academic Free License (AFL) 3.0 |
op_doi |
https://doi.org/10.17605/osf.io/f6qpz |
_version_ |
1766332755981893632 |