Giudicarie Line

  (Redirected from Giudicárie line)
Geology of the Alps
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 Giudicarie Line is a major geologic fault zone in the Italian Alps, named for the Giudicarie valleys area. It runs from Meran in the northeast more or less straight 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 north 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 off to the west at the upper Val di Sole, where it is called the Tonale line. The northeast-oriented 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.


  • G. Prosser, 1998: Strike-slip movements and thrusting along a transpressive fault zone: The North Giudicarie line (Insubric line, northern Italy) in Tectonics, v 17, p 921–937
  • S. Martin, G. Bigazzi, M. Zattin, G. Viola & M.L. Balestrieri, 1998: Neogene kinematics of the Giudicarie fault (Central-Eastern Alps, Italy): new apatite fission-track data in Terra Nova v 10, p 217
  • Frisch, W.; Dunkl, I. & Kuhlemann, J.; 2000: Post-collisional large-scale extension in the Eastern Alps in Tectonophysics v 327, p239