Rueras-Gneiskomplex

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Representation and status

Index
G-T
Color CMYK
(0%,16%,16%,2%)
Color RGB
R: 220 G: 180 B: 160
Rank
lithostratigraphic Formation
Validity
Unit is in Use
Status
informal term

Nomenclature

Deutsch
Rueras-Gneiskomplex
Français
Complexe gneissique de Rueras
Italiano
Complesso gneissico di Rueras
English
Rueras Gneiss Complex
Origin of the Name

Rueras (GR), Tujetsch

Historical Variants

Paragneise + Paraschiefer (Niggli 1944), Rueras Gneiss Complex (Berger et al. 2017), Rueras-Gneiskomplex (Gisler 2018)

Description

Description

Niggli 1944: Paragneis (inkl. Hornfles) + Paraschiefer (mit Quarzit) + Amphibolit/Grünschiefer + Ultrabasika

Age

Age at top
  • Paleozoic
Age at base
  • Precambrian

Geography

Type area
Tujetsch (GR)

References

Definition
Berger Alfons, Mercolli Ivan, Herwegh Marco, Gnos Edwin (2017) : Geological Map of the Aar Massif, Tavetsch and Gotthard Nappes. Geological Special Map 1:100'000, Explanatory Notes 129

p.61: NIGGLI (1944) subdivided the metasedimentary gneisses into “Paragneise” and “Paraschiefer” to emphasise the important difference between these two rock types. The “Paragneise” show an Alpine overprint of pre-Alpine higher-grade metamorphic assemblages at upper greenschist-facies metamorphic conditions. Relics of such earlier parageneses, particularly in amphibolites and ultramafic rocks, allowed BIINO (1994, 1995) to reconstruct its pre-Alpine history. In contrast, the “Paraschiefer” were very strongly affected by a pervasive Alpine metamorphic and tectonic overprint at greenschist-facies conditions, completely obliterating previous mineral assemblages. On the present map sheet, these two types of metasedimentary gneisses were grouped together into the Rueras Gneiss Complex (GT).

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