Van der Baan, M. (2002) Constant Q and a fractal, stratifed Earth. Pure and Applied Geophysics, 159 (7-8). pp. 1707-1718. ISSN 1420-9136Full text available as:
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Frequency dependent measurements of the quality factor Q typically show a constant behaviour for low frequencies and a positive power law dependence for higher frequencies. In particular, the constant Q pattern is usually explained using intrinsic attenuation models due to anelasticity with either a single or multiple superposed relaxation mechanisms - each with a particular resonance peak. However, in this study, I show using wave localisation theory that a constant Q may also be due to apparent attenuation due to scattering losses. Namely, this phenomenon occurs if the Earth displays fractal characteristics. Moreover, if fractal characteristics exist over a limited range of scales only, even an absorption band can be created - in accordance with observations. This indicates that it may be very difficult to distinguish between intrinsic and scattering attenuation on the basis of frequency dependent measurements of the quality factor only.
|Copyright, Publisher and Additional Information:||Copyright, © 2002 Birkha¨user Verlag. This is an author produced electronic version of an article accepted for publication in Pure and Applied Geophysics.|
|Keywords:||attenuation, fractals, inhomogeneous media, scattering, wave propagation|
|Institution:||The University of Leeds|
|Academic Units:||The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds)|
|Depositing User:||Repository Officer|
|Date Deposited:||04 Mar 2005|
|Last Modified:||05 Jun 2014 07:08|