Corpo ultramafico della Val Malenco
Representation and status
- Color CMYK
- (22%,0%,38%,37%)
- Color RGB
- R: 125 G: 160 B: 100
- Rank
- tectonically bounded lithostratigraphic unit
- Validity
- Unit is in Use
- Status
- informal term
Nomenclature
- Deutsch
- Val-Malenco-Ultramafititkörper
- Français
- Corps ultramafique du Val Malenco
- Italiano
- Corpo ultramafico della Val Malenco
- English
- Val Malenco ultramafic body
- Origin of the Name
- Historical Variants
-
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.
- Thickness
- 1200-1500 m (Spillmann 1993)
Hierarchy and sequence
- Upper boundary
-
Margna-Decke
- Lower boundary
-
Lanzada-Sermendone-Zone (Avers- und Suretta-Decke)
References
- Definition
-
(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
- Rank
- lithostratigraphic unit
- Status
- local name (informal)
- In short
- Ophikarbonat des Val-Malenco-Ultramafititkörpers, diskordant zu den alpinen Strukturen streichend.
-
Ur-Brekzie
- Name Origin
- Rank
- tectonically bounded lithostratigraphic unit
- Status
- informal term
- In short
- Ophikarbonate bzw. tektonische Brekzie am Kontakt zwischen der Margna-Decke und dem Malenco-Serpentinit.
-
Oficarbonati di Scermendone
- Name Origin
- Rank
- lithostratigraphic unit
- Status
- local name (informal)
- In short
- Ophikarbonate mit Sedimentstrukturen (Gradierung) des Val-Malenco-Ultramafititkörpers.
-
Gabbro del Monte Braccia
- Name Origin
- Rank
- lithostratigraphic Formation
- Status
- informal term
- In short
- Gabbroide Intrusion im Bereich der Krusten-Mantel-Grenze (d.h. zwischen Margna- und Malenco-Decke).
- Age
- Cisuralian (= Early Permian)
-
Serpentinite della Val Malenco
- Name Origin
- Rank
- lithostratigraphic unit
- Status
- informal term
- In short
-
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
- Bajocian