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

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

Research output: Contribution to journalArticlepeer-review

4 Citations (SciVal)

Abstract

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.

Original languageEnglish
Pages (from-to)77-87
Number of pages11
JournalJournal of African Earth Sciences
Volume127
DOIs
Publication statusPublished - 2017 Mar 1

Subject classification (UKÄ)

  • Geology

Keywords

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

Fingerprint

Dive into the research topics of 'New constraints on the geochronology and Sm-Nd isotopic characteristics of Bas-Drâa mafic dykes, Anti-Atlas of Morocco'. Together they form a unique fingerprint.

Cite this