Leutschenberg-Member

Rappresentazione e statuto

Colore CMYK

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

Colore RGB

R: 245 G: 160 B: 70

Rango

Membro litostratigrafico (Sotto-formazione)

Uso

Unità in uso.

Status

termine formale valido

Nomenclatura

Deutsch

Leutschenberg-Member

Français

Membre du Leutschenberg

Italiano

Membro del Leutschenberg

English

Leutschenberg Member

Origine del nome

Leutschenberg (AG), WSW Zeglingen

Varianti storiche

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

Descrizione

Descrizione

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

Potenza

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

Componenti

• crinoidi

Gerarchia e successione

Unità di rango superiore

• Schinznach-Formation

Unità di rango inferiore

• Fützen-Bank

Unità sovrastante

• Kienberg-Member

Unità sottostante

• Zeglingen-Formation (Anhydritgruppe)

Limite superiore

Kienberg-Member.

Limite inferiore

Stromatolitischer Dolomit der Zeglingen-Formation.

Età

Geomorfologia

• Anisico

Età alla base

• Anisico

Geografia

Estensione geografica

Nordschweizer Jura.

Regione-tipo

Aargauer Jura

Località-tipo

• Leutschenberg (AG), W-Flank
  Caratteristiche del sito
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Coordinate
  • (2636950 / 1251250)
  Nota
  • Merki 1961 Fig.8, Pietsch et al. 2016 Fig.8

Sezione-tipo

• Leutschenberg (AG), W-Flank
  Caratteristiche del sito
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Coordinate
  • (2636950 / 1251250)
  Nota
  • Merki 1961 Fig.8, Pietsch et al. 2016 Fig.8

Paleogeografia e tettonica

• Trias (Jura)

Paleogeografia

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

Termini generici

• Jura :
  Juragebirge

Tipo di origine

• sedimentaria

Metamorfismo

non metamorfo

Facies metamorfica

• dolomitizzazione secondaria

Referenze

Definizione

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.

Pubblicazioni importanti

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