Abstract
Three-dimensional seismic ray tracing through thermally derived slab models is used to investigate the effects of subducting lithosphere on teleseismic earthquake locations in island arcs. Theoretical results show teleseismic mislocations are greatest in the thrust zone and become negligible seaward of the trench. Varying the thermal coefficient of seismic velocity and the depth of penetration of the model slab have pronounced effects on mislocations while variations in assumed slab thickness have only minor effects. Variations in station distributions used to locate island arc events can result in 10 km differences in determined epicenters for the same event.Comparison with observed mislocations gives a range of conceivable models for the central Aleutian slab varying from a 360 km depth of penetration with a thermal coefficient of -0.0009 km/s-dC to a 600 km deep slab withpv/pT=-0.0005 km/s-dC. The best fit model extends to 360 km depth with a thermal coefficient of -0.0009 km/s-dC. Theoretical mislocations indicate that intermediate depth events are well located teleseismically. Spurious dips and thinning of the Benioff zone can result from mislocations of deeper events.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
