1887
Volume 73, Issue 8
  • E-ISSN: 1365-2478
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Abstract

ABSTRACT

We present a robust method for inverting magnetic data to estimate the three‐dimensional (3D) shape of a single targeted source in the presence of non‐targeted sources, without requiring prior filtering of interfering signals. Assuming knowledge of the total magnetization direction of the target, our method retrieves its total magnetization intensity, position and shape. The target is approximated by a set of vertically juxtaposed prisms with the same magnetization vector and thickness. Each prism's horizontal section is defined by a polygon with equally spaced vertices from to . The parameters to be estimated during inversion include the positions of the vertices, the horizontal location of each prism and the prism's thickness. The method uses a regularized non‐linear inversion with a data‐misfit function defined by L1‐norm data residuals (L1‐misfit solution). Tests on synthetic data demonstrate that the L1‐misfit solution outperforms the L2‐misfit solution in retrieving the 3D shape of the targeted source in the presence of non‐targeted sources. In the absence of interfering signals, both solutions yield similar results. Real data applications to the Anitápolis and Diorama alkaline complexes in Brazil suggest that both complexes are controlled by faults, consistent with published geological information.

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2025-10-14
2025-11-09
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  • Article Type: Research Article
Keyword(s): inversion; magnetic; potential field

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