Greywacke zone
From Wikipedia, the free encyclopedia
| Geology of the Alps |
|---|
 |
| Tectonic subdivision |
| Penninic nappes |
| Austroalpine nappes |
| Southern Alps |
| Formations & rocks |
| Geological structures |
|
Aarmassif | Dent Blanche klippe | Engadine window | Flysch zone | Giudicárie line | Greywacke zone | Hohe Tauern window | Molasse basin | Penninic thrustfront | Periadriatic Seam | Ivrea zone | Lepontin dome | Rechnitz window | Rhône-Simplon line | Sesia unit |
| Paleogeografic terminology |
| Briançonnais microcontinent |
| Piemont-Liguria Ocean |
| Apulian or Adriatic plate |
The greywacke zone is a band of Paleozoic sedimentary rocks in the Austrian Alps. The zone is part of the Austroalpine nappes.
Mesozoic limestones crop out north of the greywacke zone, forming the Northern Calcareous Alps. South of the zone basement rocks of the Austroalpine and Penninic nappes form the Central Eastern Alps.
The lithologies of the greywacke zone are:
- Paleozoic turbidites (among them greywackes) and limestones of Ordovician to Devonian age.
- felsic and mafic volcanic rocks of Ordovician age
The rocks have formed at a passive margin of the Paleo-Tethys Ocean, when the Austroalpine terrane was part of the microcontinent Avalonia. Together with the other Austroalpine units, they were thrusted over the European plate during the Alpine orogeny.
