Choosing the ‘best’ double couple from a moment-tensor inversion
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Abstract:
General moment-tensor solutions contain double couples, compensated linear vector dipoles (CLVD's) and isotropic sources. Since double-couple solutions are considered to be standard, it is important to find the best double-couple solution that is consistent with the original solution. It is proved that for a number of reasonable measures of fit, the best double couple is the one formed by removing a CLVD source with a magnitude of the intermediate non-zero eigenvalue. It is also shown that mixtures of double couple and CLVD's may result from near-source changes in rigidity.Keywords:
Moment tensor
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Near‐source velocity structure and isotropic moment tensors: A case study of the Long Valley Caldera
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