Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska
International audience Alaska is located at the northernmost point of the interface between the Pacific plate and the North American continent. The subduction of the Pacific plate generates arc volcanoes along the Aleutian trench, which stops to the east at the Denali Volcanic Gap. This volcanic gap...
Published in: | Geochemistry, Geophysics, Geosystems |
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Format: | Article in Journal/Newspaper |
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Online Access: | https://hal.science/hal-04496324 https://hal.science/hal-04496324/document https://hal.science/hal-04496324/file/Millet_etal_G3_2023.pdf https://doi.org/10.1029/2022gc010374 |
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ftunivlyon1:oai:HAL:hal-04496324v1 2024-06-23T07:45:03+00:00 Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska Millet, Florian Rondenay, Stéphane Bodin, Thomas Tape, Carl Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE) École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL) Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) University of Bergen (UiB) University of Alaska Fairbanks (UAF) 2023 https://hal.science/hal-04496324 https://hal.science/hal-04496324/document https://hal.science/hal-04496324/file/Millet_etal_G3_2023.pdf https://doi.org/10.1029/2022gc010374 en eng HAL CCSD AGU and the Geochemical Society info:eu-repo/semantics/altIdentifier/doi/10.1029/2022gc010374 hal-04496324 https://hal.science/hal-04496324 https://hal.science/hal-04496324/document https://hal.science/hal-04496324/file/Millet_etal_G3_2023.pdf doi:10.1029/2022gc010374 info:eu-repo/semantics/OpenAccess ISSN: 1525-2027 EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-04496324 Geochemistry, Geophysics, Geosystems, 2023, 24 (11), pp.e2022GC010374. ⟨10.1029/2022gc010374⟩ [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2023 ftunivlyon1 https://doi.org/10.1029/2022gc010374 2024-05-27T14:29:51Z International audience Alaska is located at the northernmost point of the interface between the Pacific plate and the North American continent. The subduction of the Pacific plate generates arc volcanoes along the Aleutian trench, which stops to the east at the Denali Volcanic Gap. This volcanic gap has been linked to the underthrusting of the Yakutat terrane, which might alter the thermal state of the mantle wedge and prevent melt formation. This implies that the limits of the volcanic activity should mirror the extent of the Yakutat subduction. However, the transition from the Pacific slab to the Yakutat terrane at depth is not fully understood. To investigate this issue, we processed a new composite seismic data set from six arrays deployed in the region from 2000 to 2018. We apply a multi-mode 3D Kirchhoff migration to obtain high-resolution 3D scattering images of the region. Our results highlight a sharp lateral boundary in the slab structure, with a 10 km Moho step, just offshore Anchorage, and a more gradual slab transition beneath the southern part of the Kenai peninsula. Our images from the Yakutat slab plunge down to 150 km depth are consistent with previous estimates of the Yakutat slab extent below the Alaska Range. Although the steeply dipping boundaries of the subducting Pacific lithospheres are not fully recovered, deep coherent signals from the Pacific slab are observed down to 150 km depth. These observations suggest that the crust is still partially uneclogitized at these depths in both slabs. Article in Journal/Newspaper alaska range Yakutat Alaska HAL Lyon 1 (University Claude Bernard Lyon 1) Anchorage Pacific Geochemistry, Geophysics, Geosystems 24 11 |
institution |
Open Polar |
collection |
HAL Lyon 1 (University Claude Bernard Lyon 1) |
op_collection_id |
ftunivlyon1 |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Millet, Florian Rondenay, Stéphane Bodin, Thomas Tape, Carl Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience Alaska is located at the northernmost point of the interface between the Pacific plate and the North American continent. The subduction of the Pacific plate generates arc volcanoes along the Aleutian trench, which stops to the east at the Denali Volcanic Gap. This volcanic gap has been linked to the underthrusting of the Yakutat terrane, which might alter the thermal state of the mantle wedge and prevent melt formation. This implies that the limits of the volcanic activity should mirror the extent of the Yakutat subduction. However, the transition from the Pacific slab to the Yakutat terrane at depth is not fully understood. To investigate this issue, we processed a new composite seismic data set from six arrays deployed in the region from 2000 to 2018. We apply a multi-mode 3D Kirchhoff migration to obtain high-resolution 3D scattering images of the region. Our results highlight a sharp lateral boundary in the slab structure, with a 10 km Moho step, just offshore Anchorage, and a more gradual slab transition beneath the southern part of the Kenai peninsula. Our images from the Yakutat slab plunge down to 150 km depth are consistent with previous estimates of the Yakutat slab extent below the Alaska Range. Although the steeply dipping boundaries of the subducting Pacific lithospheres are not fully recovered, deep coherent signals from the Pacific slab are observed down to 150 km depth. These observations suggest that the crust is still partially uneclogitized at these depths in both slabs. |
author2 |
Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE) École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL) Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) University of Bergen (UiB) University of Alaska Fairbanks (UAF) |
format |
Article in Journal/Newspaper |
author |
Millet, Florian Rondenay, Stéphane Bodin, Thomas Tape, Carl |
author_facet |
Millet, Florian Rondenay, Stéphane Bodin, Thomas Tape, Carl |
author_sort |
Millet, Florian |
title |
Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
title_short |
Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
title_full |
Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
title_fullStr |
Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
title_full_unstemmed |
Seismic Imaging of the Westward Transition From Yakutat to Pacific Subduction in Southern Alaska |
title_sort |
seismic imaging of the westward transition from yakutat to pacific subduction in southern alaska |
publisher |
HAL CCSD |
publishDate |
2023 |
url |
https://hal.science/hal-04496324 https://hal.science/hal-04496324/document https://hal.science/hal-04496324/file/Millet_etal_G3_2023.pdf https://doi.org/10.1029/2022gc010374 |
geographic |
Anchorage Pacific |
geographic_facet |
Anchorage Pacific |
genre |
alaska range Yakutat Alaska |
genre_facet |
alaska range Yakutat Alaska |
op_source |
ISSN: 1525-2027 EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-04496324 Geochemistry, Geophysics, Geosystems, 2023, 24 (11), pp.e2022GC010374. ⟨10.1029/2022gc010374⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2022gc010374 hal-04496324 https://hal.science/hal-04496324 https://hal.science/hal-04496324/document https://hal.science/hal-04496324/file/Millet_etal_G3_2023.pdf doi:10.1029/2022gc010374 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2022gc010374 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
24 |
container_issue |
11 |
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1802650549528559616 |