EurekaMag.com logo
+ Site Statistics
References:
53,214,146
Abstracts:
29,074,682
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Application of a global 3D model to improve regional event locations


Studia Geophysica et Geodetica 46(2): 283-292
Application of a global 3D model to improve regional event locations
Accurate location of weak seismic events is crucial for monitoring clandestine nuclear tests, for studying local seismic structures, and for assessing possible seismic hazards. Outside of a few regions with dense seismic networks, weak seismic events (with magnitude less than 4) are usually sparsely recorded at epicentral distances less than 20 degrees . Because of lateral variations in crustal and upper mantle structures, observed travel times of seismic phases deviate significantly from predictions based on 1-dimensional (ID) seismic models. Accurately locating weak seismic events remains a difficult task for modern seismology. Perhaps the most promising solution to this problem is the use of a 3-dimensional (3D) model of the Earth. Here we present the results of a validation test in which, using the 3D model SR2002 of the crust and upper mantle and regional phase data alone, we relocate approximately 200 earthquakes and nuclear explosions in Eurasia. The 3D model is constructed using surface wave dispersion data. The event locations using the 3D model are compared with so-called Ground Truth data, either known by non-seismic means or validated by cluster analysis, with location accuracy mostly 5 km or better. Typically, the 3D model reduces the location errors to about half the values attained with the ID model: i.e. approximately 18 km location errors are reduced to about 9 km. This test indicates that the location of regional events can be significantly improved by using a global 3D model.

(PDF same-day service: $19.90)

Accession: 018458470

DOI: 10.1023/a:1019858221004



Related references

The use of a 3D model to improve regional event locations. Seismological Research Letters 72(2): 228, 2001

P (sub n) and S (sub n) tomography across Eurasia to improve regional seismic event locations. Tectonophysics 358(1-4): 39-55, 2002

Use of propagation path corrections to improve regional event locations in Western Canada. Eos, Transactions, American Geophysical Union 78(46, Suppl, 1997

Initial results at reducting systematic errors for seismic event locations using a model incorporating anisotropic regional structures. Pages 404-409 2001, 2001

Improving regional event locations in the Middle East by incorporating model-based correction surfaces derived from 3-D velocity structures. Seismological Research Letters 71(2): 208-209, 2000

How can we improve a global ocean tide model at a regional scale? A test on the Yellow Sea and the East China Sea. Journal of Geophysical Research: Oceans 105(C4): 8707-8725, 2000

Global test of seismic event locations using different Earth models. Pages 420 2001, 2001

A global event with a regional character; the early Toarcian oceanic anoxic event in the Pindos Ocean northern Peloponnese, Greece. Geological Magazine 148.4, 2011

Methods of improving regional seismic event locations. Pages 298-304 2001, 2001

Improving global seismic event locations using source-receiver reciprocity. Bulletin of the Seismological Society of America 91(3): 594-603, 2001