Corpo ultramafico della Val Malenco

Représentation et statut

Couleur CMYK
(22%,0%,38%,37%)
Couleur RGB
R: 125 G: 160 B: 100
Rang
unité lithostratigraphique délimitée tectoniquement
Usage
Ce terme est en usage.
Status
terme informel

Nomenclature

Deutsch
Val-Malenco-Ultramafititkörper
Français
Corps ultramafique du Val Malenco
Italiano
Corpo ultramafico della Val Malenco
English
Val Malenco ultramafic body
Variantes historiques

Ultramafititkörper der Val Malenco (Peretti 1985), Malenco serpentinite body (Peretti 1986), rocce ultramafiche della zona Disgrazia-Malenco = ultramafiti del Disgrazia (Wenk 1992), Malenco ultramafics (Puschnig et al. 1996), Malenco-Ultramafititen = Ultramafititen des Malenco = Malencokörper(Hansmann et al. 1996), Malenco-Einheit = Malenco-Komplex (Ulrich & Borsien 1996), Ultramafititkörpers der Valmalenco (Spillmann & Trommsdrof 2007), Malenco unit (TK500 / Gouffon et al. 2024)

Description

Description

Stellt eine der grössten Ultramafititmassen (ca. 130 km2) der Alpen dar.

Épaisseur
1200-1500 m (Spillmann 1993)

Hiérarchie et succession

Limite supérieure

Margna-Decke

Limite inférieure

Lanzada-Sermendone-Zone (Avers- und Suretta-Decke)

Références

Révision
Gouffon Yves (Editor) (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).

  • Oficarbonati della Val Ventina

    Name Origin

    Val Ventina (Italia)

    Rang
    unité lithostratigraphique
    Statut
    terme local (informel)
    En bref
    Ophikarbonat des Val-Malenco-Ultramafititkörpers, diskordant zu den alpinen Strukturen streichend.
  • Ur-Brekzie

    Name Origin

    Pass d'Ur = Passo della Poschiavina (GR)

    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

    Valle Scermendone (Italia)

    Rang
    unité lithostratigraphique
    Statut
    terme local (informel)
    En bref
    Ophikarbonate mit Sedimentstrukturen (Gradierung) des Val-Malenco-Ultramafititkörpers.
  • Gabbro del Monte Braccia

    Name Origin

    Monte Braccia (Valmalenco, Italia)

    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

    Alta Val Malenco (Disgrazia, Italia)

    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
haute de page