· · · Institutional Repository



Home · About · Disclaimer · Terms of use ·
   Options
 
Faculty:
Department:
Type:
Year:

Time-domain modeling of electromagnetic diffusion with a frequency-domain code

Author: Mulder, W.A. · Wirianto, M. · Slob, E.C.
Faculty:Civil Engineering and Geosciences
Department:Geotechnology
Type:Article/Letter to the Editor
Date:2007-11-13
Publisher: Society of Exploration Geophysicists
Source:Geophysics, 73 (1), 2008
Identifier: doi:10.1190/1.2799093
ISSN: 0016-8033
Keywords: Fourier transforms · frequency-domain analysis · terrestrial electricity · time-domain analysis
Rights: © 2008 Society of Exploration Geophysicists

Abstract

We modeled time-domain EM measurements of induction currents for marine and land applications with a frequency-domain code. An analysis of the computational complexity of a number of numerical methods shows that frequency-domain modeling followed by a Fourier transform is an attractive choice if a sufficiently powerful solver is available. A recently developed, robust multigrid solver meets this requirement. An interpolation criterion determined the automatic selection of frequencies. The skin depth controlled the construction of the computational grid at each frequency. Tests of the method against exact solutions for some simple problems and a realistic marine example demonstrate that a limited number of frequencies suffice to provide time-domain solutions after piecewise-cubic Hermite interpolation and a fast Fourier transform.

Content Viewer