Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements
Dissertation (Ph.D.) University of Alaska Fairbanks, 2005 GPS geodetic measurements are used to study two major earthquakes, the 2001 MW 7.7 El Salvador and 2002 MW 7.9 Denali Fault earthquakes. The 2001 MW 7.7 earthquake was a normal fault event in the subducting Cocos plate offshore El Salvador. C...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/8777 2023-05-15T16:20:39+02:00 Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements Hreinsdottir, Sigrun Freymueller, Jeffrey T. 2005 http://hdl.handle.net/11122/8777 unknown http://hdl.handle.net/11122/8777 Department of Geology and Geophysics Geophysics Geographic information science and geodesy Geology Dissertation phd 2005 ftunivalaska 2023-02-23T21:37:08Z Dissertation (Ph.D.) University of Alaska Fairbanks, 2005 GPS geodetic measurements are used to study two major earthquakes, the 2001 MW 7.7 El Salvador and 2002 MW 7.9 Denali Fault earthquakes. The 2001 MW 7.7 earthquake was a normal fault event in the subducting Cocos plate offshore El Salvador. Coseismic displacements of up to 15 mm were measured at permanent GPS stations in Central America. The GPS data were used to constrain the location of and slip on the normal fault. One month later a MW 6.6 strike-slip earthquake occurred in the overriding Caribbean plate. Coulomb stress changes estimated from the M W 7.7 earthquake suggest that it triggered the MW 6.6 earthquake. Coseismic displacement from the MW 6.6 earthquake, about 40 mm at a GPS station in El Salvador, indicates that the earthquake triggered additional slip on a fault close to the GPS station. The MW 6.6 earthquake further changed the stress field in the overriding Caribbean plate, with triggered seismic activity occurring west and possibly also to the east of the rupture in the days to months following the earthquake. The MW 7.9 Denali Fault earthquake ruptured three faults in the interior of Alaska. It initiated with a thrust motion on the Susitna Glacier fault but then ruptured the Denali and Totschunda faults with predominantly right-lateral strike-slip motion unilaterally from west to east. GPS data measured in the two weeks following the earthquake suggest a complex coseismic rupture along the faults with two main regions of moment release along the Denali fault. A large amount of additional data were collected in the year following the earthquake which greatly improved the resolution on the fault, revealing more details of the slip distribution. We estimate a total moment release of 6.81 x 1020 Nm in the earthquake with a M W 7.2 thrust subevent on Susitna Glacier fault. The slip on the Denali fault is highly variable, with 4 main pulses of moment release. The largest moment pulse corresponds to a MW 7.5 subevent, about 40 km west of the ... Doctoral or Postdoctoral Thesis glacier Alaska University of Alaska: ScholarWorks@UA Fairbanks |
institution |
Open Polar |
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University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
unknown |
topic |
Geophysics Geographic information science and geodesy Geology |
spellingShingle |
Geophysics Geographic information science and geodesy Geology Hreinsdottir, Sigrun Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
topic_facet |
Geophysics Geographic information science and geodesy Geology |
description |
Dissertation (Ph.D.) University of Alaska Fairbanks, 2005 GPS geodetic measurements are used to study two major earthquakes, the 2001 MW 7.7 El Salvador and 2002 MW 7.9 Denali Fault earthquakes. The 2001 MW 7.7 earthquake was a normal fault event in the subducting Cocos plate offshore El Salvador. Coseismic displacements of up to 15 mm were measured at permanent GPS stations in Central America. The GPS data were used to constrain the location of and slip on the normal fault. One month later a MW 6.6 strike-slip earthquake occurred in the overriding Caribbean plate. Coulomb stress changes estimated from the M W 7.7 earthquake suggest that it triggered the MW 6.6 earthquake. Coseismic displacement from the MW 6.6 earthquake, about 40 mm at a GPS station in El Salvador, indicates that the earthquake triggered additional slip on a fault close to the GPS station. The MW 6.6 earthquake further changed the stress field in the overriding Caribbean plate, with triggered seismic activity occurring west and possibly also to the east of the rupture in the days to months following the earthquake. The MW 7.9 Denali Fault earthquake ruptured three faults in the interior of Alaska. It initiated with a thrust motion on the Susitna Glacier fault but then ruptured the Denali and Totschunda faults with predominantly right-lateral strike-slip motion unilaterally from west to east. GPS data measured in the two weeks following the earthquake suggest a complex coseismic rupture along the faults with two main regions of moment release along the Denali fault. A large amount of additional data were collected in the year following the earthquake which greatly improved the resolution on the fault, revealing more details of the slip distribution. We estimate a total moment release of 6.81 x 1020 Nm in the earthquake with a M W 7.2 thrust subevent on Susitna Glacier fault. The slip on the Denali fault is highly variable, with 4 main pulses of moment release. The largest moment pulse corresponds to a MW 7.5 subevent, about 40 km west of the ... |
author2 |
Freymueller, Jeffrey T. |
format |
Doctoral or Postdoctoral Thesis |
author |
Hreinsdottir, Sigrun |
author_facet |
Hreinsdottir, Sigrun |
author_sort |
Hreinsdottir, Sigrun |
title |
Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
title_short |
Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
title_full |
Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
title_fullStr |
Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
title_full_unstemmed |
Coseismic Deformation Of The 2001 El Salvador And 2002 Denali Fault Earthquakes From Gps Geodetic Measurements |
title_sort |
coseismic deformation of the 2001 el salvador and 2002 denali fault earthquakes from gps geodetic measurements |
publishDate |
2005 |
url |
http://hdl.handle.net/11122/8777 |
geographic |
Fairbanks |
geographic_facet |
Fairbanks |
genre |
glacier Alaska |
genre_facet |
glacier Alaska |
op_relation |
http://hdl.handle.net/11122/8777 Department of Geology and Geophysics |
_version_ |
1766008602022117376 |