Gneiss oeillé de Randa

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Representation and status

Index
GO-R
Color CMYK
(0%,56%,56%,12%)
Color RGB
R: 225 G: 100 B: 100
Rank
lithostratigraphic Formation
Validity
Unit is in Use
Status
informal term

Nomenclature

Deutsch
Randa-Augengneiss
Français
Gneiss oeillé de Randa
Italiano
Gneiss occhiadino di Randa
English
Randa Augengneiss
Origin of the Name

Randa (VS)

Historical Variants

Randagneise = Randa-Augengneise (Jäckli 1950), Orthogneis von Randa, gneiss oeillés de Randa (Bearth 1963, Steck 1984), Gneiss oeillés de Randa = granito-gneiss oeillé de Randa (Sartori & Della Valle 1986), ortogneiss di Randa (Dal Piaz et al. 1992a), Randa orthogneiss = Randa augengneiss (Bussy et al. 1996b), Randa orthogneiss (Genier et al. 2008)

Description

Description

Vorwiegend grobflaserige Augengneise (Augengneis von Randa); homogene, mittelkörnige Gneise; Aplite. Métagranite peralumineux calc-alcalin (Thélin 1987)

Hierarchy and sequence

Superordinate unit

Age

Age at top
  • Guadalupian (= Middle Permian)
Age at base
  • Cisuralian (= Early Permian)
Dating Method

269 ±2 Ma (U/PB zircon: Bussy et al. 1996).

Palaenography and tectonic

Paleogeography
Briançonnais Domain :
microcontinent briançonnais
Tectonic unit (resp. main category)
Kind of protolith
  • plutonic
Metamorphism
monocyclic
Metamorphic facies
  • greenschist facies (epizone)

References

Definition
Thélin Philippe (1987) : Nature originelles des gneiss oeillés de Randa (Nappe de Siviez-Mischabel, Valais). Mémoires de la Société Vaudoise des Sciences Naturelles 18/1, 75 pages
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