3D Magnetic Inversion in Angola: Serra da Neve Alkaline Complex and Jamba Itabirites case studies

Ana Machadinho; Patricia Represas; Daniela Alves; Domingos Cordeiro; João Carvalho; Rui Lopes; Paulo Caessa; Luis Pereira; André Osório

doi:10.21701/bolgeomin/136.1/003

Authors

Ana Machadinho Laboratório Nacional de Energia e Geologia. GeoBioTec, Nova School of Science and Technology. Geociences Center, University of Coimbra https://orcid.org/0000-0003-1323-217X
Patricia Represas Laboratório Nacional de Energia e Geologia https://orcid.org/0000-0002-2987-2836
Daniela Alves Laboratório Nacional de Energia e Geologia https://orcid.org/0009-0009-5846-2738
Domingos Cordeiro Instituto Geológico de Angola, IGEO, https://orcid.org/0000-0002-1521-5878
João Carvalho Laboratório Nacional de Energia e Geologia https://orcid.org/0000-0003-2227-3918
Rui Lopes Laboratório Nacional de Energia e Geologia, Estrada da Portela-Zambujal https://orcid.org/0009-0006-9895-0662
Paulo Caessa Laboratório Nacional de Energia e Geologia https://orcid.org/0009-0002-1435-0266
Luis Pereira Laboratório Nacional de Energia e Geologia https://orcid.org/0009-0000-1058-6058
André Osório Laboratório Nacional de Energia e Geologia https://orcid.org/0000-0003-1282-777X

DOI:

https://doi.org/10.21701/bolgeomin/136.1/003

Keywords:

3D magnetic inversion, MVI susceptibility, Serra da Neve alkaline complex, Jamba itabirites

Abstract

Demanding and speculative economies make it imperative to search for new areas of mineral exploration. Angola’s geological diversity presents an enormous potential for mineral resources. This potential can be assessed by applying different methods, such as geophysical prospecting, to discover new potential targets of areas to explore. For many years, the magnetic method has been successfully used in mineral exploration. In this work we apply a 3D magnetic inversion technique to aeromagnetic data in two different study areas. The Serra da Neve alkaline complex (SNAC) represents a potential source for rare earth elements (REE) and the Jamba itabirites provides metallic mineral deposits with iron and gold mineralizations. In both case studies, whether concerning alkaline intrusions or itabirites deposits, their magnetic properties are characterized by strong magnetic anomalies clearly delineated on magnetic anomaly maps. The high magnetic susceptibility (k) contrast between these target structures and the host rocks allowed us to obtain a coherent three-dimensional geometry for the SNAC structures and the itabirites deposits. The magnetic inversion technique also provided magnetic vector inversion (MVI) susceptibility values estimation for constituent lithologies, as well as the shape and size of the studied structures and deposits. The results demonstrate the effectiveness of the magnetic method for the detection and characterization of target areas, offering an innovative technique to identify potential areas in mineral resources exploration.

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References

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