Detached North Alpine Foreland
Representation 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
- Abgeschertes Nordalpines Vorland
- Français
- Avant-pays nord-alpin décollé
- Italiano
- Avampaese nordalpino distaccato
- English
- Detached North Alpine Foreland
- Historical Variants
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Sheared-off North Alpine Foreland, Avant-pays nordalpin décollé, Detached North Alpine Foreland (TK500 / Gouffon et al. 2024)
Description
- Description
-
Alpin deformierter europäischer Kontinentalschelf ausserhalb der Alpen s.s.
Hierarchy and sequence
- Subordinate units
Palaenography and tectonic
- Paleogeography
- North Alpine Foreland Basin
- Kind of protolith
-
- tectonic
References
- Definition
-
(2024) :
Tectonic Map of Switzerland 1:500000, Explanatory notes. Federal Office of Topography swisstopo, Wabern
p.22: The Detached North Alpine Foreland refers to the displaced sedimentary cover north of the front of the Helvetic units. The deformation began in Mid to Late Miocene and lasted, depending on the author, until the end of the Miocene, the Pliocene or is still ongoing today (see compilation and discussion in Schori 2021). Decoupling between the thrusted and deformed cover and the underlying basement took place in a décollement zone in the evaporites of Muschelkalk Group east of a line Porrentruy–Biel–Fribourg and of the Keuper Group further west (Jordan 1992). Deformation includes northwestward and northward displacement, thrusting and folding as well as strike-slip deformation. The northern boundary, which coincides with the front of Alpine deformation, is given by the outermost (distal) significant thrusting and folding. The easternmost clear evidence for décollement-related tectonics is given by the Lägern Anticline east of Baden with some more indications from seismic data found south of Bülach (Naef et al. 1995, Malz et al. 2016, Madritsch et al. 2024). Further to the east, displacement of the sedimentary cover along the decollement zone is presumed to gradually decrease. Accordingly, no precise eastern boundary can be drawn between the Detached North Alpine Foreland and the autochthonous South German Platform and a conceptual transition zone is defined instead (see § 3.2 for details).
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Subalpine Molasse
- Rank
- tectonic unit
- Status
- valid
- In short
-
The Subalpine Molasse constitutes the southernmost subdomain of the Detached North Alpine Foreland, situated between the Foreland Plateau to the north and the first basal thrust of the Alpine nappes to the south. It consists of a stack of imbricated thrust slices where the beds generally dip towards the SE. The Subalpine Molasse mainly includes coarse-grained foreland basin strata that were deposited between about 32 and 20 Ma. They chronicle the change from the underfilled Flysch to the filled/overfilled Molasse stage of foreland basin evolution.
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Vorlandplateau
- Rank
- tectonic unit
- Status
- local name (informal)
- In short
-
The Foreland Plateau covers the detached part of the Molasse Basin and its Mesozoic basement. It is characterized by NE–SW trending low amplitude folds.
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Internal Folded Jura
- Name Origin
-
Partie interne (la plus proche des Alpes) du Jura plissé, formant les plus hauts sommets de la chaîne jurassienne.
- Rank
- tectonic
- Status
- informal term
- In short
-
The Internal Folded Jura represents the most intensely deformed part of the Detached North Alpine Foreland. In a similar manner to the whole Jura Mountains, it forms a prominent arcuate chain («Haute Chaîne») in eastern France and northwestern Switzerland.
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External Folded Jura
- Name Origin
-
Partie externe (la plus éloignée des Alpes) du Jura plissé.
- Rank
- tectonic subdomain
- Status
- informal term
- In short
-
The External Folded Jura is the outermost part of the arcuate Jura mountain range (and hence of the Detached Northern Alpine Foreland) consisting of low-relief Plateaux, only slightly faulted, separated from each other by narrow, highly deformed Faisceaux.
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Abgescherter Tafeljura
- Rank
- tectonic unit
- Status
- local name (informal)
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«Vorfaltenzone»
- Rank
- tectonic unit
- Status
- informal term
- In short
-
The «Vorfaltenzone» is a faisceaux-type fold belt of the External Folded Jura, partly hidden by the overthrust Internal Folded Jura.
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zone des Avant-Monts
- Rank
- tectonic zone
- Status
- valid
- In short
-
Région monoclinale, localement plissée, de la partie frontale du Jura (zone préjurassienne) chevauchant le plateau de Haute-Saône (bordure oriental du Bassin de Paris) par l'intermédiaire de la faille de l'Ognon. Cette zone constitue l'ultime front compressif du Jura.
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Faisceaux
- Rank
- tectonic unit
- Status
- local name (informal)
- In short
-
The Faisceaux are narrow zones of intense deformation of the External Folded Jura. They separate largely undeformed or only slightly deformed tabular areas known as Plateaux.
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Mandacher Störung
- Name Origin
- Rank
- tectonic
- Status
- informal term
- In short
-
The Mandach Thrust is considered as the northern boundary of the Detached North Alpine Foreland.
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«Vorfaltenzone»
- Rank
- tectonic unit
- Status
- informal term
- In short
-
The «Vorfaltenzone» is a faisceaux-type fold belt of the External Folded Jura, partly hidden by the overthrust Internal Folded Jura.
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Plateaux
- Rank
- tectonic unit
- Status
- local name (informal)
- In short
-
The Plateaux are largely undeformed or only slightly deformed tabular areas of the External Folded Jura. They are separated by narrow zones of intense deformation known as Faisceaux.
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Bözberg Plateau
- Name Origin
- Rank
- tectonic
- Status
- local name (informal)
- In short
-
The Bözberg Plateau is a small plateau of the External Folded Jura, detached for a few hundreds of meters to the north. It is limited to the north by the frontal Mandach Thrust and to the south by the «Vorfaltenzone» (partly hidden by the overthrust Internal Folded Jura).