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Representation and status

Color CMYK
Color RGB
R: 225 G: 130 B: 170
lithostratigraphic unit
Unit is in Use


Radiolarite de la Falotta
Falotta Radiolarite
Origin of the Name

Falotta (GR)

Historical Variants
Manganerz-Mine Falotta im roten Kieselschiefern und Radiolariten (Dietrich & Peters 1969), manganese deposits near Falotta = Mangan-Vererzungen in Oberhalbstein = manganerzhaltige Radiolarite des Oberhalbstein-Gebietes (Graeser et al. 1984)
Nomenclatorial Remarks
Radiolarit-Kieselschiefer-Gruppe (Dietrich 1969), Radiolarite Formation (Manatschal & Nievergelt 1997), Radiolarit der Platta-Decke


1-5 m (Manatschal & Nievergelt 1997)


Age at top
  • Jurassic
Age at base
  • Jurassic


Type area
Oberhalbstein (GR)


Graeser S., Schwander H., Suhner B. (1984) : Grischunit (CaMn2[AsO4I2]), eine neue Mineralart aus den Schweizer Alpen - zur Mn-As-Mineralisation des Oberhalbstein-Gebietes. Schweiz. mineral. petrogr. Mitt. 64/1, 1-10
Manatschal Gianreto, Nievergelt Peter (1997) : A continent-ocean transition recorded in the Err and Platta nappes (Eastern Switzerland). Eclogae geol. Helv. 90/1, 3-27

p.9: The first sediments found on both continental and oceanic basement, defining the base of the post-rift sedimentary sequence, belong to the upper Middle to Upper Jurassic Radiolarite Formation (Baumgartner 1987). They are composed of thin bedded, siliceous shales and cherts (Fig. 3). The whole formation is usually not thicker than 40 m in the Austroalpine units and about 1 to 5 m in the ophiolitic cover sequences. Because of the polyphase Alpine deformation, undisturbed stratigraphie contacts with the underlying lithologies are rare. In the Radiolarite Formation of the Piatta ophiolitic cover. Dietrich (1970) described angular clasts of dolomite, gneiss, schist, spinel and serpentinite in sedimentary breccias. Coarse grained detritus originating from a continental as well as from an oceanic source in breccias of the Radiolarite Formation in the Tigias unit, which is characterized by an Austroalpine Mesozoic sedimentary sequence (see later and Fig. 17). suggests a close proximity of the Piatta and Err domains in Late Jurassic time.
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