The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here:

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Ulf Söderlund

Ulf Söderlund


Ulf Söderlund

Mapping mafic dyke swarms, structural features, and hydrothermal alteration zones in Atar, Ahmeyim and Chami areas (Reguibat Shield, Northern Mauritania) using high-resolution aeromagnetic and gamma-ray spectrometry data


  • Moussa Hamath Ba
  • Mohammed Jaffal
  • Khalidou Lo
  • Nasrrddine Youbi
  • Mohamed El Mokhtar Dahmada
  • Hassan Ibouh
  • Moulay Ahmed Boumehdi
  • Tahar Aïfa
  • Massinissa Amara
  • Mark Jessell
  • Richard E. Ernst
  • Mohamed Khalil Bensalah
  • Ulf Söderlund

Summary, in English

Analysis of an airborne geophysical data covering the Tasiast-Tijirit Terrane in the western part of the Reguibat Shield (including the 1:200,000 geological sheets of Chami, Ahmeyim and Atar), provided an improved mapping of mafic dyke swarms, structural features, and hydrothermal alteration zones. It also extended the mapping into extensive areas covered by sand. A low-altitude (100 m) airborne survey collected high-resolution magnetic and gamma-ray spectrometry data. The magnetic data were enhanced using techniques such as reduction to the pole, analytic signal and first vertical derivative, and revealed dyke swarms with trends of NNE-SSW to NE-SW, NW-SE to WNW-ESE and E-W. The use of the Euler deconvolution method provided constraints on the continuity and the depth of magnetic sources. Gamma-ray spectrometry which maps the three main radioactive elements, i.e. potassium, uranium and thorium helped discriminate lithological units of the Archean basement, notably felsic intrusions. The radiometric data also helped delineate potassic alteration zones, which could testify to hydrothermal activities of relevance to sulfide mineralisation.


  • Lithosphere and Biosphere Science

Publishing year





Journal of African Earth Sciences



Document type

Journal article




  • Geology


  • Gamma-ray spectrometry
  • Mafic dyke
  • Magnetism
  • Mauritania
  • Reguibat shield
  • Terrane Tasiast-Tijirit




  • ISSN: 1464-343X