Leutschenberg-Member

Darstellung und Status

Farbe CMYK

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

Farbe RGB

R: 245 G: 160 B: 70

Rang

lithostratigraphisches Member (Subformation)

Gebrauch

Element ist in Gebrauch

Status

gültiger formeller Begriff

Nomenklatur

Deutsch

Leutschenberg-Member

Français

Membre du Leutschenberg

Italiano

Membro del Leutschenberg

English

Leutschenberg Member

Herkunft des Namens

Leutschenberg (AG), WSW Zeglingen

Historische Varianten

Unterer Trochitenkalk, Leutschenberg Member (Pietsch et al. 2016)

Beschreibung

Beschreibung

Bioturbierter, oft dolomitisierter Kalk (Mudstone bis Wackestone) an der Basis der Schinznach-Formation. Im unteren Teil treten lokal Crinoid- («Trochitenkalk») und Schalentrümmer auf.

Mächtigkeit

4 - 10 m (Merki 1961, Pietsch et al. 2016).

Komponenten

• Crinoideen

Hierarchie und Abfolge

Übergeordnete Einheit

• Schinznach-Formation

Untergeordnete Einheiten

• Fützen-Bank

Hangendes

• Kienberg-Member

Liegendes

• Zeglingen-Formation (Anhydritgruppe)

Obergrenze

Kienberg-Member.

Untergrenze

Stromatolitischer Dolomit der Zeglingen-Formation.

Alter

Alter Top

• Anisien

Alter Basis

• Anisien

Geografie

Geographische Verbreitung

Nordschweizer Jura.

Typusregion

Aargauer Jura

Typlokalität

• Leutschenberg (AG), W-Flank
  Merkmale des Ortes
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Koordinaten
  • (2636950 / 1251250)
  Notizen
  • Merki 1961 Fig.8, Pietsch et al. 2016 Fig.8

Typusprofil

• Leutschenberg (AG), W-Flank
  Merkmale des Ortes
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Koordinaten
  • (2636950 / 1251250)
  Notizen
  • Merki 1961 Fig.8, Pietsch et al. 2016 Fig.8

Paläogeografie und Tektonik

• Trias des Juragebirges

Paläogeografie

Northern Tethyan Carbonate Platform (Jura > Helv.) :
Plateforme de Bourgogne, ... = Northern Tethyan Carbonate Platform (NTCP)

Tektonische Einheit (bzw. Überbegriff)

• Jura :
  Juragebirge

Herkunftstyp

• sedimentär

Metamorphose

unmetamorph

Metamorphosefazies

• sekundäre Dolomitisierung

Referenzen

Erstdefinition

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 Leutschenberg Member represents the lowermost part of the Schinznach Formation. It mainly consists of bioturbated mud- and wackestones. Bedding planes and burrows are often dolomitised. The basal strata are locally dolomitic (Disler 1914; Merki 1961) and overlie stromatolitic dolomites of the Zeglingen Formation (Fig. 8).

At some localities strata rich in crinoid and shell detritus occur near the base of the Leutschenberg Member (Figs. 8, 10). They are between 5 cm (Fig. 10; see Merki 1961; Gsell 1968) and about 2 m thick (Merki 1961). Merki (1961) called these strata ‘‘Basale Trochitenbank’’. They often represent the lowermost part of the Leutschenberg Member, but similar lithology may occur in middle part as well (Disler 1914; Merki 1961). Due to their multiple occurrence at different stratigraphic levels within the lower part of the Leutschenberg Member they cannot be defined as a single bed. The Basale Trochitenbank rather comprises different crinoid-detritus-rich strata. Where these strata occur at the base of the Leutschenberg Member, they often contain dolomite clasts originating from the underlying ‘‘Anhydritdolomit’’ representing the top of the Zeglingen Formation (Merki 1961).

The top of the Leutschenberg Member is defined by the first occurrence of successional float- to rudstones rich in crinoid and shell detritus above bioturbated mud- and wackestones (see below; Figs. 8, 10). Thus, the ‘‘Basale Trochitenbank’’ of Merki (1961) is defined to form part of the Leutschenberg Member.

Wichtige Publikationen

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