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Title: Mapping Tectonic Stress Using Earthquakes

Abstract

An earthquakes occurs when the forces acting on a fault overcome its intrinsic strength and cause it to slip abruptly. Understanding more specifically why earthquakes occur at particular locations and times is complicated because in many cases we do not know what these forces actually are, or indeed what processes ultimately trigger slip. The goal of this study is to develop, test, and implement a Bayesian method of reliably determining tectonic stresses using the most abundant stress gauges available - earthquakes themselves.Existing algorithms produce reasonable estimates of the principal stress directions, but yield unreliable error bounds as a consequence of the generally weak constraint on stress imposed by any single earthquake, observational errors, and an unavoidable ambiguity between the fault normal and the slip vector.A statistical treatment of the problem can take into account observational errors, combine data from multiple earthquakes in a consistent manner, and provide realistic error bounds on the estimated principal stress directions.We have developed a realistic physical framework for modelling multiple earthquakes and show how the strong physical and geometrical constraints present in this problem allow inference to be made about the orientation of the principal axes of stress in the earth's crust.

Authors:
; ;  [1]
  1. Victoria University of Wellington, PO Box 600, Wellington (New Zealand)
Publication Date:
OSTI Identifier:
20719769
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 803; Journal Issue: 1; Conference: 25. international workshop on Bayesian inference and maximum entropy methods in science and engineering, San Jose, CA (United States), 7-12 Aug 2005; Other Information: DOI: 10.1063/1.2149828; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALGORITHMS; EARTH CRUST; EARTHQUAKES; MAPPING; SLIP; STRESSES; TECTONICS; VECTORS

Citation Formats

Arnold, Richard, Townend, John, and Vignaux, Tony. Mapping Tectonic Stress Using Earthquakes. United States: N. p., 2005. Web. doi:10.1063/1.2149828.
Arnold, Richard, Townend, John, & Vignaux, Tony. Mapping Tectonic Stress Using Earthquakes. United States. doi:10.1063/1.2149828.
Arnold, Richard, Townend, John, and Vignaux, Tony. Wed . "Mapping Tectonic Stress Using Earthquakes". United States. doi:10.1063/1.2149828.
@article{osti_20719769,
title = {Mapping Tectonic Stress Using Earthquakes},
author = {Arnold, Richard and Townend, John and Vignaux, Tony},
abstractNote = {An earthquakes occurs when the forces acting on a fault overcome its intrinsic strength and cause it to slip abruptly. Understanding more specifically why earthquakes occur at particular locations and times is complicated because in many cases we do not know what these forces actually are, or indeed what processes ultimately trigger slip. The goal of this study is to develop, test, and implement a Bayesian method of reliably determining tectonic stresses using the most abundant stress gauges available - earthquakes themselves.Existing algorithms produce reasonable estimates of the principal stress directions, but yield unreliable error bounds as a consequence of the generally weak constraint on stress imposed by any single earthquake, observational errors, and an unavoidable ambiguity between the fault normal and the slip vector.A statistical treatment of the problem can take into account observational errors, combine data from multiple earthquakes in a consistent manner, and provide realistic error bounds on the estimated principal stress directions.We have developed a realistic physical framework for modelling multiple earthquakes and show how the strong physical and geometrical constraints present in this problem allow inference to be made about the orientation of the principal axes of stress in the earth's crust.},
doi = {10.1063/1.2149828},
journal = {AIP Conference Proceedings},
number = 1,
volume = 803,
place = {United States},
year = {Wed Nov 23 00:00:00 EST 2005},
month = {Wed Nov 23 00:00:00 EST 2005}
}
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