HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) References Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bowers, D. Articles by Hudson, J. A. Search for Related Content GeoRef GeoRef Citation

Defining the scalar moment of a seismic source with a general moment tensor

AWE Blacknest, Brimpton, Reading, RG7 4RS, England bowers{at}blacknest.gov.uk
Department of Applied Mathematics and Theoretical Physics University of Cambridge, Silver Street, Cambridge, CB3 9EW, England

Abstract

We compare several published definitions of the scalar moment M₀, a measure of the size of a seismic disturbance derived from the second-order seismic moment tensor M (with eigenvalues m₁ m₃ m₂). While arbitrary, a useful definition is in terms of a total moment, M^T₀ = M_I + M_D, where M_I = |M|, with M = (m₁ + m₂ + m₃)/3, is the isotropic moment, and M_D = max(|m_j – M|; j = 1, 2, 3), is the deviatoric moment. This definition is consistent with other definitions of M₀ if M is a double couple. This definition also gives physically appealing and simple results for the explosion and crack sources. Furthermore, our definitions of M^T₀, M_I and M_D are in accord with the parameterization of the moment tensor into a deviatoric part (represented by T which lies in [–1,1]) and a volumetric part (represented by k which lies in [–1, 1]) proposed by Hudson et al. (1989).

This article has been cited by other articles:

				G. Manthei Characterization of Acoustic Emission Sources in a Rock Salt Specimen under Triaxial Compression Bulletin of the Seismological Society of America, October 1, 2005; 95(5): 1674 - 1700. [Abstract] [Full Text] [PDF]

				P. G. Richards and W.-Y. Kim Equivalent Volume Sources for Explosions at Depth: Theory and Observations Bulletin of the Seismological Society of America, April 1, 2005; 95(2): 401 - 407. [Abstract] [Full Text] [PDF]

				Volume Change of Seismic Sources from Moment Tensors Bulletin of the Seismological Society of America, August 1, 2001; 91(4): 880 - 884.

				Source Depth and Mechanism Inversion at Teleseismic Distances Using a Neighborhood Algorithm Bulletin of the Seismological Society of America, December 1, 2000; 90(6): 1369 - 1383.