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Contributions to Mineralogy and Petrology

, Volume 59, Issue 1, pp 95–110 | Cite as

The genesis of wadi Magrish migmatites (N-E Sinai)

  • Ora Amit
  • Yehuda Eyal
Article

Abstract

The migmatite complex of the Magrish area is part of a large crystalline massif south of Elat. The mineralogical composition of the migmatites is very uniform. The components of the melanosome are biotite, quartz and plagioclase, with small amounts of garnet and very rarely sillimanite and those of the leucosome — quartz and plagioclase. On the basis of chemical composition of the migmatites and possible premigmatitic parent rocks, absence of orthoclase in the leucosome, similar composition of plagioclase in the leucosome and in neighbouring melanosome, and Qz:Plag values which do not plot around a cotectic line, it is concluded that migmatisation occurred in a nearly closed system, without the presence of a melt phase. Thus, injection of granitic material, metasomatism or partial anatexis as possible main formation mechanisms are rejected and metamorphic differentiation is favoured.

Keywords

Quartz Mineral Resource Formation Mechanism Close System Mineralogical Composition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Ora Amit
    • 1
  • Yehuda Eyal
    • 1
  1. 1.Department of GeologyThe Hebrew UniversityJerusalem

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