Liedertswil-Member

Représentation et statut

Couleur CMYK

(0%,35%,71%,4%)

Couleur RGB

R: 245 G: 160 B: 70

Rang

Membre lithostratigraphique (Sous-formation)

Usage

Ce terme est en usage.

Status

terme formel valide

Discussion du statut

Nomenclature

Deutsch

Liedertswil-Member

Français

Membre de Liedertswil

Italiano

Membro di Liedertswil

English

Liedertswil Member

Origine du nom

Liedertswil (BL)

Variantes historiques

Plattenkalk, Nodosus-Kalk, Liedertswil Member (Pietsch et al. 2016)

Description

Description

Grauer, plattiger bis gebankter, mikritischer Kalk (ehem. «Plattenkalk» oder «Nodosus-Kalk») mit Dolomitschlieren und -lagen. Das Liedertswil-Member besteht im unteren Teil aus Kalken reich an schaligem Detritus und makrofossilarmen Mud- und Wackestones in oberen Teil.

Épaisseur

25 - 35 m (Fischer et al. 1971) ; von 1.5 m in der Bohrung Weiach bis max. 25 m (Pietsch et al. 2016)

Hiérarchie et succession

Unité hiérarchiquement supérieure

• Schinznach-Formation

Unités hiérarchiquement subordonnées

• Eptingen-Bank
• Dünnlenberg-Bank

Unités sus-jacentes

• Stamberg-Member

Unités sous-jacentes

• Kienberg-Member

Limite supérieure

Stamberg-Member

Limite inférieure

Kienberg-Member

Âge

Âge au sommet

• Ladinien initial

Âge à la base

• Anisien tardif

Méthode de datation

Compressus- und Evolutus-Zone (Pietsch et al. 2016)

Géographie

Extension géographique

Nordschweizer Jura.

Région-type

Östlicher Faltenjura

Localité-type

• Dünnlenberg (BL), südlich Liedertswil
  Particularités du site
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Accessibilité du site
  • Grat
  Coordonnées
  • (2620930 / 1248530)
  Note
  • Merki 1961, Herold 1992, Pietsch et al. 2016 Fig.11

Typusprofil

• Dünnlenberg (BL), südlich Liedertswil
  Particularités du site
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Coordonnées
  • (2620930 / 1248530)
  Note
  • Merki 1961, Herold 1992, Pietsch et al. 2016 Fig.11

Paléogéographie et tectonique

• Trias du Jura

Paléogéographie

plateforme carbonatée nord-téthysienne :
Plateforme de Bourgogne, ... = Northern Tethyan Carbonate Platform (NTCP)

Termes génériques

• Jura :
  Juragebirge

Type de protolithe

• sédimentaire

Conditions de formation

The Liedertswil Member documents the highstand and the first phase of regression. In Northern Switzerland and adjacent southern Germany, ceratite ammonite findings are restricted to the Dünnleberg Bed proper and some overlying horizons (Pietsch et al. 2016) at the base of the member.

Métamorphisme

non métamorphique

Références

Définition

Pietsch Johannes S., Wetzel Andreas, Jordan Peter (2016) : A new lithostratigraphic scheme for the Schinznach Formation (upper part of the Muschelkalk Group of northern Switzerland). Swiss J. Geosc. 109/2, 285-307

The Liedertswil Member consists of limestones rich in shell detritus in the lower part and macrofossil-poor mud- and wackestones in the upper part. As discussed above, crinoid detritus may occur in some strata of the lower part. In most sections the Dünnlenberg Bed lies little above the base of the Liedertswil Member. Above the Dünnlenberg Bed other marl layers may occur. Locally ceratites can be found in these layers (see above; Braun 1920; Merki 1961). Strata above and below the marl layers may contain glauconite (Merki 1961; Herold 1992; Brüderlin 1969). Especially the upper part of the Liedertswil Member is often dolomitised. In some regions the dolomitised Liedertswil Member contains chert nodules (e.g. Braun 1920; Merki 1961). Within the lower parts often bedding planes and burrows are dolomitised similar to underlying members. The top of the Liedertswil Member is defined by the change from (dolomitic) limestone with single dolomitic strata to a both laterally continuous and pure dolomite. Due to the diagenetic nature of the upper boundary of the Liedertswil Member, the level of the boundary varies within the Schinznach Formation. It is therefore possible that the normally overlying Stamberg Member directly rests on the Kienberg Member, if dolomitisation is used as classification criterion and if dolomitisation affected the uppermost strata rich in crinoid detritus. In that case the Liedertswil Member is not developed as such. The oolitic interval around the boundary interval between the Liedertswil Member and the Stamberg Member is defined as Eptingen Bed. Depending on dolomitisation-depth it lies either in one or in both of these members.

Principales publications

Pietsch Johannes S., Wetzel Andreas, Jordan Peter (2016) : A new lithostratigraphic scheme for the Schinznach Formation (upper part of the Muschelkalk Group of northern Switzerland). Swiss J. Geosc. 109/2, 285-307