Effingen-Member

Rappresentazione e statuto

Index

i5-6E

Colore CMYK

35 / 20 / 25 / 0

Colore RGB

R: 195 G: 200 B: 190

Rango

Membro litostratigrafico (Sotto-formazione)

Uso

Unità in uso.

Status

termine formale valido

Nomenclatura

Deutsch

Effingen-Member

Français

Membre d'Effingen

Italiano

Membro di Effingen

English

Effingen Member

Origine del nome

Hügel Ruge oberhalb Effingen (AG), Fricktal

Varianti storiche

Effingerschichten (Moesch 1857 S.55, Moesch 1867 S.143, Tobler 1905 Tab.5b, Baltzer 1906, Rothpletz 1933, Disler 1941, Hantke 1967), couches d'Effingen (de Tribolet 1872, BRGM-Doubs), Argovien moyen = Marnes d'Effingen (Rollier 1910), Effinger Schichten = Zone à Peltoceras transversarium p.p. (Haug 1911), Marnes à ciment pyriteuses d'Effingen (Rollier 1917), Effinger Schichten (Gygi 1969, Bolliger & Burri 1970 S.73), Effingerschichten = Malm alpha (Büchi et al. 1965), Marnes d'Effingen (Enay 1966, Donzeau et al. 1997, Charollais et al. 2013, Brentini 2018), Effinger Mergel (Heitzmann & Auf der Maur 1989, Meyer 2017), Effingen Member (Gygi 2000c)

Nota sul nome

«Argovien» auct.,

Links

Synonymi

«Impressa-Mergel»

Descrizione

Descrizione

Weiche, dunkelgraue Mergel und quarzreiche Kalkmergel, fossilarm, dünngebankt. Im unteren Teil ca. 12 m schwach mergelige Kalksteine im Aargauer Jura (Gerstenhübel-Schichten). Im oberen Teil treten ebenfalls gelegentlich mergelige Kalksteinbänke auf. Sie haben jedoch keinen stratigraphischen Leitwert.

Geomorfologia

Weite, vernässte Comben und rutschendes, eher schlechtes Weideland.

Potenza

Max. 210 - 260 m, das Member keilt nach NW vollständig aus.

Componenti

• ammoniti
• echinodermi
• bivalvi

Perisphinctidae, Bivalven (Pholadomya, Goniomya, Pinna), Serpuliden, Echinodermendetritus

Gerarchia e successione

Unità di rango superiore

• Wildegg-Formation

Unità di rango inferiore

• Gerstenhübel-Bank
• Pecten-Bank (Effingen-Mb.)

Unità sovrastante

• Hornbuck-Member
• Geissberg-Member
• Villigen-Formation
• Olten-Member
• Steinibach-Member
• Balsthal-Formation
• Günsberg-Formation

Unità sottostante

• Formation du Pichoux
• Birmenstorf-Member

Limite superiore

Graduelle Zunahme des Karbonatanteils und der Dicke der Bänke (transgressive surface between sequence boundaries Ox6 and Ox7 ; Wetzel & Strasser 2001).

Limite inferiore

Die Abgrenzung des Birmenstorf-Members gegen das Effingen-Member ist z. T. problematisch, weil auch im untersten Teil des Effingen-Members lokal Kalkschwämme vorkommen. "Die Effinger Schichten beginnen über den Birmenstorfer Schichten mit der ersten Quarz-Feldspat-Schüttung." (Bolliger & Burri 1970 S.73)

Età

Geomorfologia

• Oxfordiano tardo

Osservazioni sul tetto

Bimammatum-Zone : Euaspidoceras hypselum (Oppel)

Età alla base

• Oxfordiano tardo

Osservazioni sulla base

Bifurcatus-Zone : Larcheria cf. schilli (Oppel), Dichotomoceras cf. bifurcatus (Quenstedt)

Metodo di datazione

Biostratigraphie: Ammoniten (selten) der Bifurcatus- und Bimammatum-Zone (Gygi 2000b). Das Effingen-Member ist jünger als die St-Ursanne-Formation («koralligene Rauracien»), aber zeitgleich entstanden mit dem unteren Teil der Vellerat-Formation und der Günsberg-Formation («Séquanien») (Bolliger & Burri 1970, Gygi 2000).

Geografia

Estensione geografica

Französischer Jura (Enay 1966), Schweizer Jura und schwäbische Alb in Deutschland.

Regione-tipo

Aargauer Jura

Località-tipo

• Effingen (AG)
  Caratteristiche del sito
  • typische Fazies
  Agibilità del sito
  • verschwundener Aufschluss
  Coordinate
  • (2650340 / 1260720)
  Nota
  • Hügel Ruge (Moesch 1857 und 1867, Gygi 2000c) ; nicht mehr aufgeschlossen (Diebold et al. 2005)

Sezione di riferimento

• Auenstein (AG)
  Caratteristiche del sito
  • Untergrenze
  • typische Fazies
  Agibilità del sito
  • Steinbruch, Tongrube
  Coordinate
  • (2653885 / 1252450)
  Nota
  • Steinbruch Jakobsberg (Gygi 1969 Pl.17 Profil RG37, sowie Gygi 1973 Fig.3 Profil RG226)

Punti d'interesse

• Reckingen (AG)
  Caratteristiche del sito
  • typische Fazies
  Agibilità del sito
  • Steinbruch, Tongrube
  Coordinate
  • (2665500 / 1268710)
  Nota
  • Steinbruch Obergrüt (Wetzel & Strasser 2001)

Paleogeografia e tettonica

• Malm

Paleogeografia

Argovian Basin

Termini generici

• Jura :
  Juragebirge

Tipo di origine

• sedimentaria

Condizioni di formazione

"argovien": Im Gegensatz zum langsam entstandenen Birmenstorf-Member geschah die Auffüllung des über ihm liegenden Beckens durch die Schüttung des Effingen-Member in relativ kurzer Zeit. - Zu Beginn des oberen Oxfordiens setzte eine erneute terrigene, quarzreiche Schüttung aus NW ein und hinterliess im proximalen Teil der Plattform die lagunären bis brackischen Vorbourg-Member (vorwiegend kalkig) und Röschenz-Member (vorwiegend mergelig, mit Emersionen) der Vellerat-Formation. Die grossen Tonmassen wurden jedoch über den Plattformrand hinausverfrachtet und füllten in verhältnismässig kurzer Zeit den durch eine hypothetische Abschiebung im Grundgebirge noch vertieften Trog der Effinger Schichten auf (Verschiebung eines Depotzentrums, ALLENBACH 2001, Fig 17, p. 280). Auf dem Plattformrand wuchsen weiterhin Korallen; es sind die mergeldurchsetzten Korallenrasen und -riffe der Günsberg-Formation, die sich über das von spätigen Sturmlagen gekennzeichnete Dach des Effingen-Members hinwegschoben.

Sequenza

The Effingen Beds in the Rekingen outcrop display several angular unconformities overlain by conformable packages of marl-limestone alternations. After restoration for tectonic tilt, the unconformities dip at up to 5-10° to the south. The lowermost unconfomity (1) is overlain by material identical to the underlying marl-limestone alternations. The following unconformities (2 and 3) are overlain by mudflow material enriched in blackened macrofossils. These unconformities are interpreted as slide scars which later were filled by continuing background sedimentation (1) or by material that has been displaced downward (2 and 3). The Rekingen outcrop is located above the fairly well documented northern boundary fault of the North-Swiss Permocarboniferous Trough. Supposedly, differential subsidence has led to steepening of the relief during deposition and to initiation of the slumps. In fact, all the slumps known from the Effingen beds are located above faults in the basement (Allenbach, 2001a; Fig. 5). The accumulation of the Effingen Beds corresponds to a time of enhanced subsidence (e.g., Wildi et al., 1989), and basement structures had a high potential to become re-activated. (Wetzel & Strasser 2001)

Metamorfismo

non metamorfo

Referenze

Definizione

Moesch Casimir (1857) : Das Flötzgebirge im Kanton Aargau. Neue Denkschr. schweiz. natf. Ges. 15

S.55

Revisione

Gygi R. A. (2000) : Annotated index of lithostratigraphic units currently used in the Upper Jurassic of northern Switzerland. Eclogae geol. Helv. 93/1, 125-146

p.130: Effingen Member (Moesch 1857) ; Member of the Wildegg Formation The Effingen Member (Effingerschichten) was named by Moesch (1857. p. 55). The name refers to the village of Effingen. Canton Aargau. LK 1069 Frick. Moesch (1867. p. 143) wrote that the best outcrops of the member were on the hill called Ruge north of Effingen. This hill is then the type locality of the Effingen Member although there are no outcrops at present. A reference section must then be found. A complete section of the Effingen Member was published by Gygi (1969. Pl.17. section RG 37) at coordinates 653.900/252.400 in the quarry of Jakobsberg, 1 km east of Auenstein. Canton Aargau. LK 1089 Aarau. At that time, the lower part of the Effingen Member was only known from a borehole drilled on Gerstenhübel hill (not indicated in LK 1089 Aarau) in the township of Veltheim east of Jakobsberg quarry. This part of the section is now well exposed in a road cut between the quarries of Jakobsberg (township of Auenstein) and Unteregg (township of Veltheim. Canton Aargau). This is section RG 226 that was published by Gygi (1973. Fig. 3). The upper part of section RG 226 and section RG 37 are now the reference sections of the Effingen Member. The Effingen Member is mostly a blue-gray marl with intercalated successions of marly limestones or pure limestones, respectively. The thickest limestone succession is that of the Gerstenhübel Beds (see below) in the lower Effingen Member. In the upper part of the Effingen Member there are often thin layers of sandy limestone or dolomite that are partly small turbidites (Gygi 1969. Pl. 4. Fig. 12) and partly tempestites (Gygi 1986. Fig. 7). The greatest thickness of the Effingen Member is about 260 m near Riniken. Canton Aargau (Gygi 1990c. Fig. 6). Ammonites are rare, but the age of the member could be established to be of the Bifurcatus Chron by Larcheria cf. schilli (Oppel) J 23539 and by Dichotomoceras cf. bifurcatus (Quenstedt) J 2.3543. The Euaspidoceras hypselum (Oppel) J 27259 from the upper Effingen Member indicates that sedimentation of the Effingen Member ended in the early Bimammatum Chron. All these ammonites were figured by Gygi (2000b) and are kept in the Museum of Natural History Basel. The Effingen Member can be followed (with different names) from the French Jura through Switzerland to the Swabian Alb in southern Germany.

Pubblicazioni importanti

Deplazes Gaudenz, Bläsi H.R., Schnellmann M., Traber D. (2013) : Sedimentologie und Stratigraphie der Effinger Schichten. Nagra Arbeitsbericht NAB 13-16, 145 S.

Materiale e vario

15200115