Falda di Antigorio

Darstellung und Status

Farbe CMYK

N/A

Farbe RGB

R: 241 G: 239 B: 237

Rang

Decke

Gebrauch

Element ist in Gebrauch

Status

gültig

Diskussion des Status

Nomenklatur

Deutsch

Antigorio-Decke

Français

Nappe d'Antigorio

Italiano

Falda di Antigorio

English

Antigorio Nappe

Herkunft des Namens

Valle Antigorio (Italia)

Historische Varianten

Untere Gneissmasse = Antigori-Gneiss (Gerlach 1869), nappe I = nappe d'Antigorio (Argand 1911b), Antigoriodecke (Bosshard 1925), Antigoriodecke bzw. Antigorioteildecke (Grütter 1929), Antigorio-Monte Leone-Decke (Günthert 1958), Falda Antigorio (Godenzi 1963), Antigorio-Gneismasse = Antigorio-Zone = Antigorio-Gneisszone (Wieland 1966), nappe n°1 = Antigorio nappe (Carrupt 2003), Antigorio recumbent fold (Steck 2008), Antigorio fold nappe (Steck et al. 2013), Falde di Antigorio (Della Torre & Maggini 2015), Antigorio Nappe (Gouffon et al. 2024)

Beschreibung

Beschreibung

Falda del Lepontico occidentale, con basamento cristallino paleozoico (esclusivamente ortogneiss) e copertura autoctona mesozoica (zona del Teggiolo).

Steck et al. 2013, p.430: The Antigorio fold nappe in the Antigorio (Toce) and Devero valleys is composed of three granitoid intrusions: (a) the 296 ± 2 Ma old Antigorio tonalite, (b) the dominant middle to coarse grained 290 ± 4 Ma old Antigorio granodiorite and (c) the 289 ± 4 Ma old Antigorio granite (Bergomi et al. 2007). The Antigorio granitoids are farther east intrusive in an older polycyclic and migmatitic basement. The granodiorite is also intrusive in the Paleozoic Baceno schist of the Devero valley and the Verampio window. The Pioda di Crana gneiss is dominated by a strongly foliated middle to fine grained 301 ± 4 Ma old granite gneiss (Bergomi et al. 2007). Locally and especially near the contact with the higher Mergoscia zone, polycyclic micaschists and amphibolites are common. The granodioritic and tonalitic Alpigia hornblende-biotite gneiss, here attributed to the Antigorio nappe, exhibits a regular contact with the staurolite–kyanite–garnet–micaschist of the Campo Tencia unit of the Simano nappe (Keller et al. 1980; Steck 1998; Berger et al. 2005). This contact may be tectonic or intrusive.

Hierarchie und Abfolge

Untergeordnete Einheiten

• zona della Pioda di Crana

Alter

Alter Top

• Paläogen

Bermerkungen zu Top

unsicher

Alter Basis

• Cisuralien (= Frühes Perm)

Geografie

Geographische Verbreitung

Alpi Lepontine: Val Divedro (Gondoschlucht), Valle Antigorio, Val Formazza, Val Bavona, Valle di Campo, Val di Vergeletto e Valle Onsernone.

Typusregion

Valle Antigorio (Italia)

Paläogeografie und Tektonik

Tektonische Einheit (bzw. Überbegriff)

• Antigorio

Herkunftstyp

• tektonisch

Referenzen

Erstdefinition

Gerlach Heinrich (1869) : Die penninischen Alpen, Beiträge zur Geologie der Schweiz. Neue Denkschriften allg. Ges. ges. Natf. 23

Neubearbeitung

Gouffon Yves (Editor) (2024) : Tectonic Map of Switzerland 1:500000, Explanatory notes. Federal Office of Topography swisstopo, Wabern

p.47: The Antigorio Nappe consists mainly of Variscan granitoids (ca. 290–300 Ma, Bergomi et al. 2007). In its northwestern part, this basement is surrounded by an autochthonous Mesozoic–Paleogene sedimentary cover, which could be connected to the cover of the Verampio Nappe via an early thrust syncline (§ 5.1). Late folding is responsible for two multi-kilometer-scale isoclinal structures: the Alpe Bosa-Wandfluhhorn fold and the Ziccher fold (e.g., Milnes 1974a, Steck et al. 2013).