Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska
Southeastern Alaska is dominated by strike-slip motion along the Queen Charlotte-southern Fairweather fault system (QCFS) in the south and transitions to oblique convergent motion partitioned between strike-slip motion along the Denali and northern Fairweather fault systems and thrusting along fault...
Main Author: | |
---|---|
Format: | Text |
Language: | English |
Published: |
ScholarWorks@UTEP
2009
|
Subjects: | |
Online Access: | https://scholarworks.utep.edu/open_etd/2767 https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=3766&context=open_etd |
id |
ftutep:oai:scholarworks.utep.edu:open_etd-3766 |
---|---|
record_format |
openpolar |
spelling |
ftutep:oai:scholarworks.utep.edu:open_etd-3766 2023-05-15T16:20:33+02:00 Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska Rodriguez, Hugo 2009-01-01T08:00:00Z application/pdf https://scholarworks.utep.edu/open_etd/2767 https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=3766&context=open_etd en eng ScholarWorks@UTEP https://scholarworks.utep.edu/open_etd/2767 https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=3766&context=open_etd Open Access Theses & Dissertations Alaska earthquake seismicity shallow stress tensor Geophysics and Seismology text 2009 ftutep 2023-01-23T21:22:19Z Southeastern Alaska is dominated by strike-slip motion along the Queen Charlotte-southern Fairweather fault system (QCFS) in the south and transitions to oblique convergent motion partitioned between strike-slip motion along the Denali and northern Fairweather fault systems and thrusting along faults of the St. Elias region. Geologic complications are further increased by the subduction of the Yakutat microplate beneath North America and glacial processes. By studying regional background seismicity we intend to better determine the current state of stress of southeastern Alaska from the Dixon Entrance to Yakutat Bay. Phase data was gathered for over 4000 earthquakes of depths <20 km and magnitude <5 that occurred from 1973-2005 from Alaskan and Canadian databases. We relocated these earthquakes using the Double-Difference joint hypocenter method. Two areas of interest were identified with high concentrations of seismicity after relocation calculations for the entire southeast Alaska region; Glacier Bay through Yakutat (GBY) and the area surrounding Mt. Ogden (MOG). Earthquake locations in GBY are diffuse with some isolated clusters. The MOG subregion is dominated by a large northeast to southwest trending cluster that trends along the Speel River. We used these relocations and first motion data to estimate the stress fields for earthquake clusters that formed. Only a few of the calculated stress tensors were successful in representing the region's overall tectonic signature. We combined the calculated stress information with GPS, magnetic and gravity data in order determine how plate motion is partitioned in this region and to identify other potentially active faults. Text glacier Yakutat Alaska University of Texas at El Paso: Digital Commons@UTEP Dixon Entrance ENVELOPE(-132.003,-132.003,54.416,54.416) Fairweather ENVELOPE(-61.083,-61.083,-65.017,-65.017) Glacier Bay Queen Charlotte ENVELOPE(-132.088,-132.088,53.255,53.255) |
institution |
Open Polar |
collection |
University of Texas at El Paso: Digital Commons@UTEP |
op_collection_id |
ftutep |
language |
English |
topic |
Alaska earthquake seismicity shallow stress tensor Geophysics and Seismology |
spellingShingle |
Alaska earthquake seismicity shallow stress tensor Geophysics and Seismology Rodriguez, Hugo Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
topic_facet |
Alaska earthquake seismicity shallow stress tensor Geophysics and Seismology |
description |
Southeastern Alaska is dominated by strike-slip motion along the Queen Charlotte-southern Fairweather fault system (QCFS) in the south and transitions to oblique convergent motion partitioned between strike-slip motion along the Denali and northern Fairweather fault systems and thrusting along faults of the St. Elias region. Geologic complications are further increased by the subduction of the Yakutat microplate beneath North America and glacial processes. By studying regional background seismicity we intend to better determine the current state of stress of southeastern Alaska from the Dixon Entrance to Yakutat Bay. Phase data was gathered for over 4000 earthquakes of depths <20 km and magnitude <5 that occurred from 1973-2005 from Alaskan and Canadian databases. We relocated these earthquakes using the Double-Difference joint hypocenter method. Two areas of interest were identified with high concentrations of seismicity after relocation calculations for the entire southeast Alaska region; Glacier Bay through Yakutat (GBY) and the area surrounding Mt. Ogden (MOG). Earthquake locations in GBY are diffuse with some isolated clusters. The MOG subregion is dominated by a large northeast to southwest trending cluster that trends along the Speel River. We used these relocations and first motion data to estimate the stress fields for earthquake clusters that formed. Only a few of the calculated stress tensors were successful in representing the region's overall tectonic signature. We combined the calculated stress information with GPS, magnetic and gravity data in order determine how plate motion is partitioned in this region and to identify other potentially active faults. |
format |
Text |
author |
Rodriguez, Hugo |
author_facet |
Rodriguez, Hugo |
author_sort |
Rodriguez, Hugo |
title |
Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
title_short |
Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
title_full |
Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
title_fullStr |
Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
title_full_unstemmed |
Analysis Of Shallow Seismicity And Stress Fields In Southeastern Alaska |
title_sort |
analysis of shallow seismicity and stress fields in southeastern alaska |
publisher |
ScholarWorks@UTEP |
publishDate |
2009 |
url |
https://scholarworks.utep.edu/open_etd/2767 https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=3766&context=open_etd |
long_lat |
ENVELOPE(-132.003,-132.003,54.416,54.416) ENVELOPE(-61.083,-61.083,-65.017,-65.017) ENVELOPE(-132.088,-132.088,53.255,53.255) |
geographic |
Dixon Entrance Fairweather Glacier Bay Queen Charlotte |
geographic_facet |
Dixon Entrance Fairweather Glacier Bay Queen Charlotte |
genre |
glacier Yakutat Alaska |
genre_facet |
glacier Yakutat Alaska |
op_source |
Open Access Theses & Dissertations |
op_relation |
https://scholarworks.utep.edu/open_etd/2767 https://scholarworks.utep.edu/cgi/viewcontent.cgi?article=3766&context=open_etd |
_version_ |
1766008475574337536 |