• norsk
    • English
  • English 
    • norsk
    • English
  • Login
View Item 
  •   Home
  • University of Bergen Library
  • Registrations from Cristin
  • View Item
  •   Home
  • University of Bergen Library
  • Registrations from Cristin
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Implications of 3D Seismic Raytracing on Focal Mechanism Determination

Newrkla, Katharina; Shiddiqi, Hasbi Ash; Jerkins, Annie; Keers, Henk; Ottemöller, Lars
Journal article, Peer reviewed
Accepted version
Thumbnail
View/Open
Accepted Version (3.854Mb)
URI
https://hdl.handle.net/11250/2740713
Date
2019
Metadata
Show full item record
Collections
  • Department of Earth Science [868]
  • Registrations from Cristin [5646]
Original version
Bulletin of The Seismological Society of America (BSSA). 2019, 109 (6): 2746–2754   https://doi.org/10.1785/0120190184
Abstract
The purpose of this study is to investigate apparent first‐motion polarities mismatch at teleseismic distances in the determination of focal mechanism. We implement and compare four seismic raytracing algorithms to compute ray paths and travel times in 1D and 3D velocity models. We use the raytracing algorithms to calculate the takeoff angles from the hypocenter of the 24 August 2016 Mw 6.8 Chauk earthquake (depth 90 km) in central Myanmar to the stations BFO, GRFO, KONO, and ESK in Europe using a 3D velocity model of the upper mantle below Asia. The differences in the azimuthal angles calculated in the 1D and 3D velocity models are considerable and have a maximum value of 19.6°. Using the takeoff angles for the 3D velocity model, we are able to resolve an apparent polarity mismatch where these stations move from the dilatational to the compressional quadrant. The polarities of synthetic waveforms change accordingly when we take the takeoff angles corresponding to the 3D model into account. This method has the potential to improve the focal mechanism solutions, especially for historical earthquakes where limited waveform data are available.
Publisher
Seismological Society of America
Journal
Bulletin of The Seismological Society of America (BSSA)
Copyright
Copyright 2019 Seismological Society of America

Contact Us | Send Feedback

Privacy policy
DSpace software copyright © 2002-2019  DuraSpace

Service from  Unit
 

 

Browse

ArchiveCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsDocument TypesJournalsThis CollectionBy Issue DateAuthorsTitlesSubjectsDocument TypesJournals

My Account

Login

Statistics

View Usage Statistics

Contact Us | Send Feedback

Privacy policy
DSpace software copyright © 2002-2019  DuraSpace

Service from  Unit