Blockhorizont von Bernhardzell

Rappresentazione e statuto

Colore CMYK

N/A

Colore RGB

R: 250 G: 225 B: 225

Rango

Strato litostratigrafico

Uso

Unità in uso.

Status

termine locale (informale)

Discussione del statuto

Nomenclatura

Deutsch

Blockhorizont von Bernhardzell

Français

Horizon à blocs de Bernhardzell

English

Bernhardzell Block Horizon

Origine del nome

Bernhardzell (SG)

Varianti storiche

Blockhorizont (Hofmann 1951, Hofmann 1973, Kälin & Kempf 2009), vulkanischer Blockhorizont (Hofmann 1949 und 1956), Rotmergelhorizont mit exotischen Geröllen (Hofmann 1973c), Horizont mit Impaktphänomenen (Büchi & Schlanke 1977), Malmkalk-Blockhorizont (Habicht 1987), Blockhorizont of Bernhardzell (Letsch 2018)

Descrizione

Potenza

10-15 cm (Letsch 2018)

Età

Geomorfologia

• Langhiano

Età alla base

• Langhiano

Geografia

Estensione geografica

Ostschweiz.

Località-tipo

• Bernhardzell (SG), an der Sitter
  Caratteristiche del sito
  • Obergrenze
  • Untergrenze
  • typische Fazies
  Agibilità del sito
  • Bachprofil
  Coordinate
  • (2743140 / 1260530)
  Nota
  • Hofmann 1951

Punti d'interesse

• Tüfentobel (SG)
  Caratteristiche del sito
  • typische Fazies
  Coordinate
  • (2743535 / 1255305)

Paleogeografia e tettonica

• OSM-II

Tipo di origine

• sedimentaria

Condizioni di formazione

Very distally located ejecta-layer resulting from the Ries meteorite impact (Hofmann 1973b, which caused the impact structures of the Nördlinger Ries and Steinheim craters in southern Germany (SHOEMAKER & CHAO 1961, HÜTTNER & SCHMIDT-KALER 1999).

Referenze

Revisione

Kälin Daniel, Kempf Oliver (2009) : High-resolution stratigraphy from the continental record of the Middle Miocene Northern Alpine Foreland Basin of Switzerland. N. Jb. Geol. Paläont. Abh. 254/1-2, 177-235

HOFMANN (1951) described an exotic horizon within the OSM deposits of eastern Switzerland, which comprises angular Jurassic limestone blocks of Swabian lithofacies with a size of up to 20 cm, within greenish freshwater marl. Later, HOFMANN (1973b) identified this layer as a very distally located ejecta-layer resulting from the Ries meteorite impact, which caused the impact structures of the Nördlinger Ries and Steinheim craters in southern Germany (SHOEMAKER & CHAO 1961, HÜTTNER & SCHMIDT-KALER 1999). HOFMANN (1973b) also pictured typical, impact-related shatter-cone structures. Near Bischofszell, the Ries ejecta-layer is situated approx. 80-100 m below the Schoosstobel [= Leimbach] bentonite, and approx. 180-200 m below the Waldkirch/Mollen bentonite (Fig. 5).

Numerical ages of the Ries meteorite impact range from 14.4–14.9 Ma (GENTNER & WAGNER 1969, STORZER et al. 1995, REICHENBACHER et al. 1998). A detailed discussion of these ages, however, is beyond the scope of our study since the age of the Ries impact is not crucial to our correlations.

Pubblicazioni importanti

Letsch Dominik (2018) : Diamictites and soft sediment deformation related to the Ries (ca. 14.9 Ma) meteorite impact: the "Blockhorizont" of Bernhardzell (Eastern Switzerland). Int. J. Earth Sci. (Geol. Rundschau) 107, 1379-1380

Habicht J. K. A. (1987) : Schweizerisches Mittelland (Molasse). Internationales Stratigraphisches Lexikon Vol.1 Fasc.7b