Nappe des Gets
Retour à nappe des GetsReprésentation et statut
- Index
- Gt
- Couleur CMYK
- N/A
- Couleur RGB
- R: 241 G: 239 B: 237
- Rang
- nappe
- Usage
- Ce terme est en usage.
- Status
- valide
Nomenclature
- Deutsch
- Gets-Decke
- Français
- Nappe des Gets
- Italiano
- Falda dei Gets
- English
- Gets Nappe
- Origine du nom
-
Les Gets (Haute-Savoie, France)
- Variantes historiques
-
nappe du Col des Gêts (Trümpy 1976), nappe des Gets (Plancherel 1998), Gets nappe (Bill et al. 2001)
Description
- Description
-
riche en ophiolites (cf. schistes lustrés piémontais ou Canavese ligure)
Hiérarchie et succession
- Limite inférieure
-
Les parties internes de la nappe chevauchent la nappe de la Brèche, tandis que les parties externes chevauchent la nappe de la Simme.
Âge
- Âge au sommet
-
- Campanien
- Âge à la base
-
- Cénomanien
Géographie
- Extension géographique
- Des Gets (France) à Zweisimmen.
- Région-type
- Massif des Gets (Chablais savoyard, France)
Paléogéographie et tectonique
- Paléogéographie
- bassin liguro-piémontais
- Termes génériques
- Type de protolithe
-
- ophiolitique
- Métamorphisme
- monocyclique
- Faciès métamorphique
-
- faible métamorphisme
Références
- Révision
-
(2001) :
Low-grade metamorphism of the Gets nappe (Western Alps). Schweiz. Mineral. Petrogr. Mitt. 81, 229-237
The Gets nappe is a decollement cover nappe situated in the front of the Alpine belt. This nappe was affected by very weak metamorphism, preliminary illite crystallinity data suggest anchizonal conditions (Caron and Weidmann, 1967).
[...]
The Gets nappe is composed of two series (Caron, 1972): the base of the nappe (Perrieres series) essentially comprises a composite wildflysch containing ophiolitic material (serpentinite, gabbro, basalt and diabase). deep marine deposits (radiolarite, pelagic limestone, manganiferous shale), and Palaeozoic granite, all embedded in a shaly matrix (Fig. 2). The disrupted oceanic crust, the melange of ophiolitic rocks and the chaotic sedimentation are characteristic of an accretionary prism sequence (e.g. Mascle et al., 1988; Pickering et al., 1989). Isotopic dating, trace element data and Sm-Nd isotopes of the gabbros and basalts of the Gets nappe, together with structural and stratigraphic evolution of the northwest Shoulder of the Piedmont rift indicate that. at least in part, the ophiolitic material of the Gets nappe is a remnant of the onset of the Piedmont ocean spreading (Bill et al. 1997,2000,2001).The composite wildflysch is overlain by the Hundsrück series, composed mainly of turbiditic sandstones and polygenic conglomerates of Upper Cretaceous age.