Belchen-Member
Representation and status
- Color CMYK
- (0%,12%,20%,2%)
- Color RGB
- R: 250 G: 220 B: 200
- Rank
- lithostratigraphic Member (Subformation)
- Validity
- Unit is in Use
- Status
- valid formal name
- Scs Date
- 01.01.2014
- Status discussion
-
Berg eher als Dörflein => "du Belchen" auf Französisch
Nomenclature
- Deutsch
- Belchen-Member
- Français
- Membre du Belchen
- Italiano
- Membro del Belchen
- English
- Belchen Member
- Origin of the Name
- Historical Variants
-
«Oberer Keuper» auct., «Rhät-Sandstein» auct., Rhétien (Caire 1970), Belchen Member (Jordan 2016, Jordan et al. 2016)
Description
- Description
-
Vorwiegend mittelkörnige, gutsortierte, meist karbonatfreie, quarzitische Sandsteine mit tonigen, mergeligen Zwischenlagen.
- Thickness
- bis 6 m
Hierarchy and sequence
- Superordinate unit
- Units at roof
- Units at floor
- Upper boundary
-
transgressiv
- Lower boundary
-
Einsetzen einer Sandstein-Abfolge
Age
- Age at top
-
- Rhaetian
- Age at base
-
- Rhaetian
Geography
- Geographical extent
- Nur in der Nordwestschweiz und im Bodensee-Gebiet.
- Type locality
-
-
Chilchzimmersattel (BL)
Site particularities- Obergrenze
- Untergrenze
- typische Fazies
- Strassenanschnitt / Bahnanschnitt
- (2627740 / 1246130)
- <p>Nordwestlich der Belchenflue (Erni 1910 und 1912)</p>
-
Chilchzimmersattel (BL)
- Type profile
-
-
Chilchzimmersattel (BL), am Belchen
Site particularities- Obergrenze
- Untergrenze
- typische Fazies
- Strassenanschnitt / Bahnanschnitt
- (2627740 / 1246130)
- Erni 1910 und 1912
-
Chilchzimmersattel (BL), am Belchen
Palaenography and tectonic
-
- Triassic of the Jura Mountains
- Paleogeography
- Germanic basin
- Tectonic unit (resp. main category)
-
-
Jura
:
Juragebirge
-
Jura
:
- Kind of protolith
-
- sedimentary
- Conditions of formation
-
"The lower part of the Belchen Member documents a brackish estuarine to marine environment, where open sea was located to the West, and is interpreted as a seaway connecting the Tethys with the marine Germanic Basin (Beutler and Nitsch 2005). With time the estuarine facies became progressively restricted towards east. It was replaced increasingly by shallow marine sandstones and finally by silstone and marl. This succession was later cut by regional erosion of Late Triassic or Early Jurassic age, which cut deepest in central northern Switzerland (Aare Massif–Black Forest High, e.g. Trümpy 1980)" (Jordan et al. 2016).
- Sequence
-
5. regressiver Zyklus der Klettgau-Formation.
- Metamorphism
- non metamorphic
References
- Definition
-
(2016) :
The middle to late Triassic Bänkerjoch and Klettgau formations of northern Switzerland. Swiss J. Geosc. 109/2, 257-284
The Belchen-Member (formerly “Rhät-Sandstein”) consists of partly fossiliferous coarse grained sands and greenish dark marls of estuarian to shallow marine origin. The sandstones are characterized by the bright saccharoid weathering. Due to late Triassic and early Jurassic erosion, Belchen-Member is restricted to North-western Switzerland and Lake Constance area. (Jordan et al. 2015)
Description: Predominantly middle-grained, wellsorted, mostly carbonate-free quartzitic sandstone with thin shale interlayers overlain by dark marl and claystone with sandy interlayers and burrows, bonebeds (Jordan et al. 2016).