Encyclopedia of Geomagnetism and Paleomagnetism

2007 Edition
| Editors: David Gubbins, Emilio Herrero-Bervera

Reduction to Pole

  • Dhananjay Ravat
Reference work entry
DOI: https://doi.org/10.1007/978-1-4020-4423-6_275
Introduced by Baranov ( 1957) (see also, Baranov and Naudy, 1964), the reduction‐to‐pole transformation of total field magnetic anomalies (see crustal magnetic field) is intended to remove the skewness of the anomalies (see Figure R1). The transformation makes the anomalies overlie the sources, makes it possible to correlate the magnetic anomalies with other types of geophysical anomalies (e.g., gravity) and geological information, and aids their interpretation. In reality, even the amplitude of the anomaly is affected (increased) when sources of induced magnetization are observed at poles in comparison to lower magnetic latitudes because the Earth's field intensity increases from equator to poles; some of the reduction‐to‐pole methods can take this change in amplitude into account (e.g., equivalent source method) while the others typically do not (e.g., rectangular coordinate wavenumber domain methods). The expression of a magnetic anomaly, Δ T, due to a localized spherical source of...
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© Springer-Verlag 2007

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  • Dhananjay Ravat

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