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: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

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

Professor

Ulf Söderlund

New constraints on the geochronology and Sm-Nd isotopic characteristics of Bas-Drâa mafic dykes, Anti-Atlas of Morocco

Author

  • Abdelhakim El Bahat
  • Moha Ikenne
  • Brian Cousens
  • Ulf Söderlund
  • Richard Ernst
  • Martin B. Klausen
  • Nasrrddine Youbi

Summary, in English

The Precambrian inliers of the Anti-Atlas belt across the southern part of Morocco contain numerous mafic dyke and sill swarms, which are thought to represent the erosional remnants of Proterozoic Large Igneous Provinces (LIPs). As part of an extended research campaign to date and characterize these LIPs, two amphiboles from one dyke within the Bas-Drâa inlier (western Anti-Atlas) yielded consistent 40Ar-39Ar ages of 611 Ma ± 1.3; i.e., evidence of magmatic activity during the Ediacaran (635-542 Ma). Furthermore, Nd isotope ratios and model ages identifies four groups of dykes within the Bas-Drâa inlier, all of which were derived from a previously enriched mantle reservoir with very low 143Nd/144Nd ratios (0.51065–0.51170) and corresponding εNd(t) values (−16.44 to −2.45). Such low Nd-ratios arguably reflect either a contribution of crustal components, such as the Paleoproterozoïc schisto-granitic basement, or metasomatic modification of the sub-continental lithospheric mantle.

Department/s

  • Lithosphere and Biosphere Science

Publishing year

2017-03-01

Language

English

Pages

77-87

Publication/Series

Journal of African Earth Sciences

Volume

127

Document type

Journal article

Publisher

Elsevier

Topic

  • Geology

Keywords

  • Anti-Atlas
  • Ar–Ar geochronology
  • Bas-Drâa
  • Mafic dykes
  • Model age
  • Sm-Nd
  • West African Craton

Status

Published

ISBN/ISSN/Other

  • ISSN: 1464-343X