Falda Malenco-Forno-Lizun
Représentation et statut
- Couleur CMYK
- N/A
- Couleur RGB
- R: 241 G: 239 B: 237
- Rang
- nappe
- Usage
- Ce terme est en usage.
- Status
- valide
Nomenclature
- Deutsch
- Malenco-Forno-Lizun-Decke
- Français
- Nappe de Malenco-Forno-Lizun
- Italiano
- Falda Malenco-Forno-Lizun
- English
- Malenco-Forno-Lizun Nappe
- Variantes historiques
-
Ophiolithzug Val Maroz-Malenco (Staub 1921), Zone von Châtillon-Malenco (Staub 1942b), Malenker Ophiolith-Decken (Staub 1946), Zone Disgrazia-Val Malenco (Roesli 1946), Forno-Decke, Monte-del-Forno-Serie (Ferrario & Montrasio 1976), Monte-del-Forno-Komplex (Peretti 1985), Falda ofiolitica Malenco-Forno (Sciesa 1991), Malenco-Forno-Lizun-Einheit (Spillmann 1993), Malenco-Forno-Lizun units (Manatschal 1995), Malenco-Forno-Lizun-Decke (Spillmann & Trommsdorff 2007), Malenco-Forno-Lizun Nappe (TK500 / Gouffon et al. 2024), cf. Trommsdorff et al. 1993
Description
- Description
-
Reliktischer exhumierter subkontinentaler Mantel, ozeanischer Basalt und Sedimente.
Hiérarchie et succession
- Unités hiérarchiquement subordonnées
- Limite supérieure
-
Margna-Decke (Unterostalpin)
Géographie
- Extension géographique
- Tiefste tektonische Einheit der Bernina-Gruppe.
Références
- Définition
- (1921) : Geologische Karte der Val Bregaglia (Bergell ; 1:50'000). Geologische Spezialkarte 90
- Révision
-
(2024) :
Tectonic Map of Switzerland 1:500000, Explanatory notes. Federal Office of Topography swisstopo, Wabern
p.78: Three units with distinct lithological assemblages of oceanic origin, situated in adjacent areas, form the Malenco-Forno-Lizun Nappe. The Malenco unit (Montrasio et al. 2005) consists of large volumes of serpentinite that represent exhumed subcontinental mantle formerly exposed at the ocean floor, and, in a small area adjacent to the Margna Nappe, a transition into continental lower crust in Permian granulite facies, associated with a Permian gabbroic intrusion (Müntener & Hermann 1996). Further north, the Forno unit consists of metabasalts and metagabbros of oceanic origin covered by metasedimentary rocks of Jurassic to Early Cretaceous age, which are in direct contact with the roof of the Bregaglia Intrusion (Puschnig 1998, Froitzheim et al. 1996 a). The Lizun unit, located around the Piz Lizun, northwest of the Engadine Fault and sinistrally offset from the Forno unit (Schmid & Froitzheim 1993), exposes same rocks of oceanic origin as in this latter unit (Liniger & Nievergelt 1990). The Malenco-Forno-Lizun Nappe, together with the Platta Nappe, is located in the hangingwall of the Turba Normal Fault (Nievergelt et al. 1996).
- Principales publications
-
(1993) : From magmatism through metamorphism to sea floor emplacement of subcontinental Adria lithosphere during pre-Alpine rifting (Malenco, Italy). Schweiz. mineral. petrogr. Mitt. 73, 191-203
-
Lizun-Grünschiefer
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
-
Metabasika der Malenco–Forno–Lizun-Decke nördlich der Engadiner-Linie. Metasedimente fehlen in dieser Region.
-
Complesso del Monte del Forno
- Name Origin
- Rang
- unité lithostratigraphique délimitée tectoniquement
- Statut
- terme informel
- En bref
-
Within the Upper Penninic Malenco-Forno-Lizun Nappe, the Forno unit is situated southeast of the Engadine Fault and is sinistrally offset from the Lizun unit. It consists of metabasalts and metagabbros of oceanic origin covered by metasedimentary rocks of Jurassic to Early Cretaceous age, which are in direct contact with the roof of the Bregaglia Intrusion.
-
Quarziti del Muretto
- Name Origin
-
Val Muretto (GR), östlich des Malojapasses
- Rang
- Formation lithostratigraphique
- Statut
- terme informel
- En bref
- Schistes quartzeux à diopside et plagioclase (bytownite). Le protolithe devait être une arkose à matrice argileuse et ciment carbonaté (Mützenberg 1986).
- Age
- Crétacé Tardif
-
Formazione dei Rossi
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
- Metasedimente (kalkhaltige Andalusit-Granat-Biotitschiefer) des Monte-del-Forno-Komplexes.
- Age
- Jurassique Tardif
-
Quartziti di base
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
- Quarzit mit lokal zwischengeschaltete Amphibol-Pyroxen-Grünschiefer, Mn-Silikate und kalksilikat-führende Marmore.
-
Anfibolite del Forno
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
- Getüpfelter (gefleckter) bis gebänderter Amphibolit (MORB-Metabasalt ; Gautschi 1980) mit Porphyroblasten aus metamorphem Plagioklas. Pillowstrukturen (mit Epidotschlieren und Kalksilikatlagen als «Interpillow-Sedimente») und Hyaloklastite sind lokal erhalten.
- Age
- Callovien
-
Ofiolite del Forno
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
- Ophiolithsequenz des Monte-del-Forno-Komplexes.
-
Corpo ultramafico della Val Malenco
- Name Origin
- Rang
- unité lithostratigraphique délimitée tectoniquement
- Statut
- terme informel
- En bref
-
Within the Upper Penninic Malenco-Forno-Lizun Nappe, the Malenco unit consists of large volumes of serpentinite that represent exhumed subcontinental mantle formerly exposed at the ocean floor, and, in a small area adjacent to the Margna Nappe, a transition into continental lower crust in Permian granulite facies, associated with a Permian gabbroic intrusion.
-
Oficarbonati della Val Ventina
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme local (informel)
- En bref
- Ophikarbonat des Val-Malenco-Ultramafititkörpers, diskordant zu den alpinen Strukturen streichend.
-
Ur-Brekzie
- Name Origin
- Rang
- unité lithostratigraphique délimitée tectoniquement
- Statut
- terme informel
- En bref
- Ophikarbonate bzw. tektonische Brekzie am Kontakt zwischen der Margna-Decke und dem Malenco-Serpentinit.
-
Oficarbonati di Scermendone
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme local (informel)
- En bref
- Ophikarbonate mit Sedimentstrukturen (Gradierung) des Val-Malenco-Ultramafititkörpers.
-
Gabbro del Monte Braccia
- Name Origin
- Rang
- Formation lithostratigraphique
- Statut
- terme informel
- En bref
- Gabbroide Intrusion im Bereich der Krusten-Mantel-Grenze (d.h. zwischen Margna- und Malenco-Decke).
- Age
- Cisuralien (= Permien précoce)
-
Serpentinite della Val Malenco
- Name Origin
- Rang
- unité lithostratigraphique
- Statut
- terme informel
- En bref
-
Grüner bis rostrotbraun anwitternder, Chlorit und/oder Brucit führender, magnetitreicher Antigoritschiefer mit wechselndem Gehalt an Diopsid und Olivin. Schwarze, gelängte Erzaggregate, die zur Hauptsache aus Magnetit bestehen, treten häufig vor.
- Age
- Bajocien