Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms
Abstract An M W 7.1 ~ 50-km-deep intraslab earthquake within the Pacific/Yakutat slab underlying the North American Plate struck Anchorage, southern Alaska, on November 30, 2018. The ground-motion records very close to the source region of the Anchorage earthquake provide an important opportunity to...
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Springer Science and Business Media LLC
2020
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Online Access: | http://dx.doi.org/10.1186/s40623-020-01315-x http://link.springer.com/content/pdf/10.1186/s40623-020-01315-x.pdf http://link.springer.com/article/10.1186/s40623-020-01315-x/fulltext.html |
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crspringernat:10.1186/s40623-020-01315-x 2023-05-15T18:44:38+02:00 Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms Guo, Yujia Miyakoshi, Ken Tsurugi, Masato 2020 http://dx.doi.org/10.1186/s40623-020-01315-x http://link.springer.com/content/pdf/10.1186/s40623-020-01315-x.pdf http://link.springer.com/article/10.1186/s40623-020-01315-x/fulltext.html en eng Springer Science and Business Media LLC https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 CC-BY Earth, Planets and Space volume 72, issue 1 ISSN 1880-5981 Space and Planetary Science Geology journal-article 2020 crspringernat https://doi.org/10.1186/s40623-020-01315-x 2022-01-04T16:17:32Z Abstract An M W 7.1 ~ 50-km-deep intraslab earthquake within the Pacific/Yakutat slab underlying the North American Plate struck Anchorage, southern Alaska, on November 30, 2018. The ground-motion records very close to the source region of the Anchorage earthquake provide an important opportunity to better understand the source characteristics of intraslab earthquakes in this subduction zone. We estimated the kinematic rupture process during this earthquake using a series of strong-motion waveform (0.05–0.4 Hz) inversions. Our inversions clearly indicate that the Anchorage earthquake was a rare intraslab event with simultaneous rupture on two conjugate faults, which are recognized sometimes for shallow crustal earthquakes but rarely for deep intraslab earthquakes. Interestingly, one of the conjugate faults had low aftershock productivity. This fault extends to great depth and may reflect a deep oceanic Moho or a local low-velocity and high- V P / V S zone within the oceanic mantle. Even though the Anchorage earthquake was a rare event due to the conjugate faults, we found that its kinematic source parameters such as the slip amplitude and large slip area nearly equal the global averages derived from source scaling relationships for intraslab earthquakes. Because the source parameters comparable to the global averages were also found for another large intraslab earthquake in the subducting Pacific/Yakutat slab, these source parameters are likely an important source characteristic common to this subduction zone. Article in Journal/Newspaper Yakutat Alaska Springer Nature (via Crossref) Anchorage Pacific Earth, Planets and Space 72 1 |
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Springer Nature (via Crossref) |
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crspringernat |
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English |
topic |
Space and Planetary Science Geology |
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Space and Planetary Science Geology Guo, Yujia Miyakoshi, Ken Tsurugi, Masato Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
topic_facet |
Space and Planetary Science Geology |
description |
Abstract An M W 7.1 ~ 50-km-deep intraslab earthquake within the Pacific/Yakutat slab underlying the North American Plate struck Anchorage, southern Alaska, on November 30, 2018. The ground-motion records very close to the source region of the Anchorage earthquake provide an important opportunity to better understand the source characteristics of intraslab earthquakes in this subduction zone. We estimated the kinematic rupture process during this earthquake using a series of strong-motion waveform (0.05–0.4 Hz) inversions. Our inversions clearly indicate that the Anchorage earthquake was a rare intraslab event with simultaneous rupture on two conjugate faults, which are recognized sometimes for shallow crustal earthquakes but rarely for deep intraslab earthquakes. Interestingly, one of the conjugate faults had low aftershock productivity. This fault extends to great depth and may reflect a deep oceanic Moho or a local low-velocity and high- V P / V S zone within the oceanic mantle. Even though the Anchorage earthquake was a rare event due to the conjugate faults, we found that its kinematic source parameters such as the slip amplitude and large slip area nearly equal the global averages derived from source scaling relationships for intraslab earthquakes. Because the source parameters comparable to the global averages were also found for another large intraslab earthquake in the subducting Pacific/Yakutat slab, these source parameters are likely an important source characteristic common to this subduction zone. |
format |
Article in Journal/Newspaper |
author |
Guo, Yujia Miyakoshi, Ken Tsurugi, Masato |
author_facet |
Guo, Yujia Miyakoshi, Ken Tsurugi, Masato |
author_sort |
Guo, Yujia |
title |
Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
title_short |
Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
title_full |
Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
title_fullStr |
Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
title_full_unstemmed |
Simultaneous rupture on conjugate faults during the 2018 Anchorage, Alaska, intraslab earthquake (MW 7.1) inverted from strong-motion waveforms |
title_sort |
simultaneous rupture on conjugate faults during the 2018 anchorage, alaska, intraslab earthquake (mw 7.1) inverted from strong-motion waveforms |
publisher |
Springer Science and Business Media LLC |
publishDate |
2020 |
url |
http://dx.doi.org/10.1186/s40623-020-01315-x http://link.springer.com/content/pdf/10.1186/s40623-020-01315-x.pdf http://link.springer.com/article/10.1186/s40623-020-01315-x/fulltext.html |
geographic |
Anchorage Pacific |
geographic_facet |
Anchorage Pacific |
genre |
Yakutat Alaska |
genre_facet |
Yakutat Alaska |
op_source |
Earth, Planets and Space volume 72, issue 1 ISSN 1880-5981 |
op_rights |
https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1186/s40623-020-01315-x |
container_title |
Earth, Planets and Space |
container_volume |
72 |
container_issue |
1 |
_version_ |
1766235422493507584 |