Mittelpenninikum
Back to Middle PenninicRepresentation and status
- Color CMYK
- N/A
- Color RGB
- R: 241 G: 239 B: 237
- Rank
- tectonic domain
- Validity
- Unit is in Use
- Status
- valid
Nomenclature
- Deutsch
- Mittelpenninikum
- Français
- Pennique moyen
- Italiano
- Pennidico medio
- English
- Middle Penninic
- Historical Variants
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Mittelpenninische Decken (Trümpy 1974), Pennidico medio (Dal Piaz et al. 1992a), Mittlere Penninische Decken (Gruber et al. 2010), Middle Penninic Subdomain (TK500 / Gouffon et al. 2024)
Description
- Description
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Die lithostratigraphische Einheiten die die mittelpenninischen Decken bilden stammen paläogeographisch aus der Briançonnais-Schwelle (NE Teil des Iberischen Kontinents). Sie wurden also zwischen den Valais-Ozean im Norden und den Piemont-Ligurischen Ozean im Süden abgelagert.
In the Western Alps, they were formerly known as the «Grand St-Bernard Nappe».
Hierarchy and sequence
Palaenography and tectonic
- Paleogeography
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Briançonnais Terrane
:
microcontinent briançonnais
- Tectonic unit (resp. main category)
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(Internal) Middle Penninic of Western Switzerland
- Rank
- tectonic subdomain
- Status
- local name (informal)
- In short
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In Western Switzerland, the Middle Penninic subdomain comprises units located between the Sion-Courmayeur Nappe and the Tsaté and Zermatt-Saas nappes. These units were first grouped together within the “Grand St-Bernard Nappe” (Argand 1911), which was then subdivided into several nappes.
The Middle Penninic units are thought to be derived from the Briançonnais Terrane, which consisted of a polycyclic crystalline basement cut by Late Cambrian (ca. 500 Ma) and Permian (ca. 270 Ma) granitic intrusions, Permo-Carboniferous sediments that filled narrow basins and a characteristic Mesozoic – Paleogene sedimentary cover. Much of this Briançonnais cover was detached at the level of the Triassic evaporites to form some of the nappes in the Prealps.
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Internal Middle Penninic of Eastern Switzerland
- Rank
- tectonic subdomain
- Status
- local name (informal)
- In short
-
In eastern Switzerland, the internal part of the Middle Penninic is represented by the Tambo and Suretta basement-cover nappes and, additionally, by detached sedimentary nappes. Structurally, the Suretta Nappe occupies the core of the very large-scale north facing Niemet-Beverin Backfold that postdates nappe stacking and can be followed all the way into the Prättigau Half-Window. The sedimentary Schams Nappe Complex and the upper part of the Lower Penninic Tomül Nappe are wrapped around the Suretta Nappe in this mega-fold and backthrust to the southeast in an overturned position over the top of the Suretta Nappe and of the Upper Penninic Avers Nappe. The Mesozoic strata in all these Middle Penninic units can definitely be attributed to the Briançonnais paleogeographic realm.