The amplitude and phase of the derivatives of the magnetic anomalies of thin dykes and contacts
Gordon R. J. Cooper
+ Author Affiliations
- Author Affiliations
School of Geosciences, University of the Witwatersrand, Johannesburg 2050, South Africa. Email: gordon.cooper@wits.ac.za
Exploration Geophysics 47(4) 290-295 https://doi.org/10.1071/EG16012
Submitted: 3 February 2016 Accepted: 3 May 2016 Published: 10 June 2016
Abstract
If the horizontal and vertical derivatives of the total field magnetic anomalies of thin dykes and contacts (and the magnetic anomaly from a thin dyke) are put into an amplitude-phase form, then this can aid in their interpretation. First, it allows derivatives of fractional order to be calculated analytically; second, estimates of the source dip can be made; and finally, the relationships between local wavenumber and source-distance semi-automatic interpretation methods are clarified. The approach is demonstrated on synthetic data and aeromagnetic data from South Africa.
Key words: magnetics, semiautomatic interpretation, potential fields.
References
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