The Neogene Randen Fault, with a maximum vertical offset of about 250 m, forms - together with the Schiener Berg Fault - the southwestern limit of the central part of the Hegau-Bodensee Graben.
The Lower Helvetic tectonic subdomain comprises all the sedimentary and crystalline units below the Glarus (eastern Switzerland), Axen (central Switzerland), Diablerets and Wildhorn major thrusts (western Switzerland). It corresponds to the External Crystalline Massifs and what was formerly called the “Infrahelvetic complex” that includes imbricates with North Helvetic facies as well as sedimentary nappes with South Helvetic to Ultrahelvetic facies.
