Unterer Teil der Schrattenkalk-Formation

Représentation et statut

Index
c4-5u
Couleur CMYK
(31%,0%,13%,24%)
Couleur RGB
R: 135 G: 195 B: 170
Rang
Membre lithostratigraphique (Sous-formation)
Usage
Ce terme est en usage.
Status
terme incorrect (mais utilisé de manière informelle)

Nomenclature

Deutsch
Unterer Teil der Schrattenkalk-Formation
Français
Partie inférieure de la Formation du Schrattenkalk
Italiano
Parte inferiore della Formazione dello Schrattenkalk
English
Lower part of the Schrattenkalk Formation
Variantes historiques

Unterurgon bzw. Unterer Caprotinenkalk (Baltzer 1906), Oberes Barrémien = Unterer Schrattenkalk (Urgonfazies) (Furrer 1938), Unterer Schrattenkalk (Schindler 1959), Lower Schrattenkalk Member (Föllmi et al. 2007)

Description

Description

Hellgrau anwitternder, dickbankiger, fossilarmer Kalk.

Géomorphologie
Helle Felswand.
Épaisseur
Bis über 100 m (Föllmi et al. 2007)

Hiérarchie et succession

Unité hiérarchiquement supérieure
Unités sus-jacentes

Âge

Âge au sommet
  • Aptien initial
Âge à la base
  • Barrémien tardif
Note sur la base

Mitte spätes Barremian 

Paléogéographie et tectonique

  • Crétacé moyen
  • Crétacé de l'Helvétique
Paléogéographie
plateforme nord téthysienne :
marge continentale européenne
Termes génériques
Type de protolithe
  • sédimentaire
Métamorphisme
non métamorphique

Références

Révision
Föllmi Karl B., Bodin Stephane, Godet Alexis, Linder Pascal, van de Schootbrugge B. (2007) : Unlocking paleo- environmental information from Early Cretaceous shelf sediments in the Helvetic Alps: stratigraphy is the key! Swiss J. Geosci. 100, 349-369

p.11: The lower Schrattenkalk reaches a maximal thickness of over 100 m and is composed of carbonate pack- and grainstone rich in ooids, peloids, benthic foraminifera (e.g., miliolids, orbitolinids), green algae, rudists (e.g., Requienia), bryozoans, brachiopods, bivalves, echinoderms and corals. This unit is characterized by a strong progradational trend (Fig. 2) and by a rather rapid transition (within a few kilometers; Fichter 1934; Bollinger 1988) into the outer shelf marls and marl-limestone alternations of the Tierwis Formation [Hurst Beds]. The entire succession is considered as a second-order systems tract, which may form one single sequence with the underlying Drusberg Member and the Chopf Bed (Funk et al. 1993). It is not excluded that third-order sequence-stratigraphic subdivisions may be present within the lower Schrattenkalk, as is the case in the Vercors area (Arnaud et al. 1998).
The age of the lower Schrattenkalk is indicated by the ammonite fauna of the Chopf Bed and by orbitolinids in the overlying Rawil Member (see below) and can be constrained as sartousiana to oglanlensis zones. A diachrony of its base along a proximal-distal axis is highly probable and due to the progradational character of this unit.

haute de page