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Volume 68, Issue 7
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

Inversion of magnetic data is complicated by the presence of remanent magnetization, and it provides limited information about the magnetic source because of the insufficiency of data and constraint information. We propose a Fourier domain transformation allowing the separation of magnetic anomalies into the components caused by induced and remanent magnetizations. The approach is based on the hypothesis that each isolated source is homogeneous with a uniform and specific Koenigsberger ratio. The distributions of susceptibility and remanent magnetization are subsequently recovered from the separated anomalies. Anomaly components, susceptibility distribution and distribution of the remanent and total magnetization vectors (direction and intensity) can be achieved through the processing of the anomaly components. The proposed method therefore provides a procedure to test the hypotheses about target source and magnetic field, by verifying these models based on available information or information from geology. We test our methods using synthetic and real data acquired over the Zhangfushan iron‐ore deposit and the Yeshan polymetallic deposit in eastern China. All the tests yield favourable results and the obtained models are helpful for the geological interpretation.

© 2020 European Association of Geoscientists & Engineers © 2020 European Association of Geoscientists & Engineers
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2020-07-14
2024-04-19

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Separation of magnetic anomalies into induced and remanent magnetization contributions
Geophysical Prospecting 68, 2320 (2020); https://doi.org/10.1111/1365-2478.12993
/content/journals/10.1111/1365-2478.12993
/content/journals/10.1111/1365-2478.12993
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  • Article Type: Research Article
Keyword(s): Data processing; Inversion; Magnetics; Modelling; Potential field

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