Giudicárie line

Geology of the Alps
Tectonic subdivision

Helvetic Zone

Penninic nappes
Austroalpine nappes
Southern Alps
Formations & rocks

Bündner schist | flysch | molasse

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

Paleogeographic terminology

Valais Ocean

Briançonnais zone
Piemont-Liguria Ocean
Apulian or Adriatic plate

The Giudicárie line is a major geologic faultzone in the Italian Alps, named for the Giudicarie valleys area. It runs from Meran in the northeast as a more or less straight line along the lower part of the Val di Sole, along the Val Rendena (upper Sarca valley) and then along the Chiese valley to the Lago d'Idro (Idro Lake).

The northern part of the line is part of the Periadriatic Seam that separates the Southern Alps from the nappe stacks of the Central Alps and runs from west to east along the Alpine mountain chain. The Periadriatic Seam branches of to the west at the upper Val di Sole, where it is called Tonale line. In fact the northeast orientated Giudicárie line off-sets the (east-west) Periadriatic Seam by 100 kilometers.

The fault zone contains older (Tertiary) mylonites, showing it was a ductile shearzone in that period. These mylonites have been overprinted by brittle thrusting still active today. The northwest dipping fault plane serves as a dextral transform fault as well as a compressive thrust fault.

References