Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA
The Kodiak Islands lie near the southern terminus of the 1964 Great Alaska earthquake rupture area and within the Kodiak subduction zone segment. Both local and trans-Pacific tsunamis were generated during this devastating megathrust event, but the local tsunami source region and the causative fault...
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ftboisestateu:oai:scholarworks.boisestate.edu:geo_facpubs-1688 2023-10-29T02:37:41+01:00 Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA Ramos, Marlon D. Liberty, Lee M. Haeussler, Peter J. Humphreys, Robert 2022-10-01T07:00:00Z application/pdf https://scholarworks.boisestate.edu/geo_facpubs/682 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1688/viewcontent/Liberty__Lee__2022__Upper_plate_structure___pub.pdf unknown ScholarWorks https://scholarworks.boisestate.edu/geo_facpubs/682 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1688/viewcontent/Liberty__Lee__2022__Upper_plate_structure___pub.pdf http://creativecommons.org/licenses/by-nc/4.0/ Geosciences Faculty Publications and Presentations Alaska Alaska earthquake 1964 bathymetry continental crust continental shelf crust CGISS Earth Sciences Geophysics and Seismology text 2022 ftboisestateu 2023-09-29T15:23:56Z The Kodiak Islands lie near the southern terminus of the 1964 Great Alaska earthquake rupture area and within the Kodiak subduction zone segment. Both local and trans-Pacific tsunamis were generated during this devastating megathrust event, but the local tsunami source region and the causative faults are poorly understood. We provide an updated view of the tsunami and earthquake hazard for the Kodiak Islands region through tsunami modeling and geophysical data analysis. Using seismic and bathymetric data, we characterize a regionally extensive seafloor lineament related to the Kodiak shelf fault zone, with focused uplift along a 50-km-long portion of the newly named Ugak fault as the most likely source of the local Kodiak Islands tsunami in 1964. We present evidence of Holocene motion along the Albatross Banks fault zone, but we suggest that this fault did not produce a tsunami in 1964. We relate major structural boundaries to active forearc splay faults, where tectonic uplift is collocated with gravity lineations. Differences in interseismic locking, seismicity rates, and potential field signatures argue for different stress conditions at depth near presumed segment boundaries. We find that the Kodiak segment boundaries have a clear geophysical expression and are linked to upper-plate structure and splay faulting. The tsunamigenic fault hazard is higher for the Kodiak shelf fault zone when compared to the nearby Albatross Banks fault zone, suggesting short wave travel paths and little tsunami warning time for nearby communities. Text Kodiak Alaska Boise State University: Scholar Works |
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Open Polar |
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Boise State University: Scholar Works |
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ftboisestateu |
language |
unknown |
topic |
Alaska Alaska earthquake 1964 bathymetry continental crust continental shelf crust CGISS Earth Sciences Geophysics and Seismology |
spellingShingle |
Alaska Alaska earthquake 1964 bathymetry continental crust continental shelf crust CGISS Earth Sciences Geophysics and Seismology Ramos, Marlon D. Liberty, Lee M. Haeussler, Peter J. Humphreys, Robert Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
topic_facet |
Alaska Alaska earthquake 1964 bathymetry continental crust continental shelf crust CGISS Earth Sciences Geophysics and Seismology |
description |
The Kodiak Islands lie near the southern terminus of the 1964 Great Alaska earthquake rupture area and within the Kodiak subduction zone segment. Both local and trans-Pacific tsunamis were generated during this devastating megathrust event, but the local tsunami source region and the causative faults are poorly understood. We provide an updated view of the tsunami and earthquake hazard for the Kodiak Islands region through tsunami modeling and geophysical data analysis. Using seismic and bathymetric data, we characterize a regionally extensive seafloor lineament related to the Kodiak shelf fault zone, with focused uplift along a 50-km-long portion of the newly named Ugak fault as the most likely source of the local Kodiak Islands tsunami in 1964. We present evidence of Holocene motion along the Albatross Banks fault zone, but we suggest that this fault did not produce a tsunami in 1964. We relate major structural boundaries to active forearc splay faults, where tectonic uplift is collocated with gravity lineations. Differences in interseismic locking, seismicity rates, and potential field signatures argue for different stress conditions at depth near presumed segment boundaries. We find that the Kodiak segment boundaries have a clear geophysical expression and are linked to upper-plate structure and splay faulting. The tsunamigenic fault hazard is higher for the Kodiak shelf fault zone when compared to the nearby Albatross Banks fault zone, suggesting short wave travel paths and little tsunami warning time for nearby communities. |
format |
Text |
author |
Ramos, Marlon D. Liberty, Lee M. Haeussler, Peter J. Humphreys, Robert |
author_facet |
Ramos, Marlon D. Liberty, Lee M. Haeussler, Peter J. Humphreys, Robert |
author_sort |
Ramos, Marlon D. |
title |
Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
title_short |
Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
title_full |
Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
title_fullStr |
Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
title_full_unstemmed |
Upper-Plate Structure and Tsunamigenic Faults Near the Kodiak Islands, Alaska, USA |
title_sort |
upper-plate structure and tsunamigenic faults near the kodiak islands, alaska, usa |
publisher |
ScholarWorks |
publishDate |
2022 |
url |
https://scholarworks.boisestate.edu/geo_facpubs/682 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1688/viewcontent/Liberty__Lee__2022__Upper_plate_structure___pub.pdf |
genre |
Kodiak Alaska |
genre_facet |
Kodiak Alaska |
op_source |
Geosciences Faculty Publications and Presentations |
op_relation |
https://scholarworks.boisestate.edu/geo_facpubs/682 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1688/viewcontent/Liberty__Lee__2022__Upper_plate_structure___pub.pdf |
op_rights |
http://creativecommons.org/licenses/by-nc/4.0/ |
_version_ |
1781062687619284992 |