Main roe stone formation

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Lithostratigraphy of the South German Jura .
Abbreviations:
  • Humph.-Fm. = Humphriesioolite Formation
  • L.Bk-Fm = Lying bench lime formation
  • H.Bk-Fm = hanging bank lime formation
  • Zm-Fm = cement marl formation
  • S.-Fm = Solnhofen formation
  • Rö.-Fm = Rögling formation
  • U.-Fm = Usseltal formation
  • Mö.-Fm = Mörnshein formation
  • N.-Fm = Neuburg formation
  • R.-Fm = Rennertshofen formation

    • The Hauptrogenstein Formation (formerly only Hauptrogenstein) is a lithostratigraphic formation of the southern German Jura . It is underlain by the Ostreenkalk Formation and overlaid by the Varians Marl Formation . It is only developed in the Upper Rhine Valley, but extends further west across Switzerland to western France. In the Swabian Alb area, it is represented by the Dentalienton and Hamitenton formation , which merge into the Sengenthal formation in East Württemberg. It reaches a maximum thickness of over 80 m. It includes the upper bajocium and the deeper subathonium .

    history

    The main roe rock formation consists mainly of calcareous oolites, which are composed of relatively large, originally calcitic ooids. These oolites are also called roe stones in German-speaking countries . This term has been in use since the 16th century. To distinguish it from the thin roe stones of the Buntsandstein, the roe stones of the southern German Jura were called "main roe stones" very early on. In the course of the consistent division of the South German Jura into formations, the name Hauptrogenstein Formation was proposed in 2005 by Gert Bloos, Gerd Dietl and Günter Schweigert.

    Definition and distribution area

    The main roe stone formation in Germany is limited to the Upper Rhine area. The deposit is erosively separated from deposits of the same age in the Swabian Alb. The interlocking with the Dentalienton or Hamitenton formation is no longer preserved. However, it has its continuation in Switzerland and to western France, where it can reach thicknesses of over 200 m. In Germany the maximum thickness is about 80 m. The formation consists predominantly of yellowish-whitish calcoolites in a sparitic matrix . Shill layers are stored which contain nerinees , corals , sea ​​lilies and sea ​​urchins . The deposits of the main roe rock formation represent a large carbonate platform. Here, ooids were formed in the shallow, moving water and washed into large bars.

    Temporal scope and breakdown

    The main roe stone formation is biostratigraphically dated in the upper Bajocian and in the lower Bathonian . A formal subdivision has not yet been made. At the top of the formation, an Eisenoolithic bank intervenes locally.

    Usable rocks

    The oolites of the main roe stone formation were important natural stones in the areas of distribution of the formation. Schenkenberg Castle was partly built with main roe stone.

    Individual evidence

    1. ↑ Hans Murawski: Geological Dictionary. , 11th edition, Enke Verlag, Stuttgart 2004, 262 pages, ISBN 978-3-827-41445-8
    2. ^ Building history of the Schenkenberg ruins by Beat Stöckli ( Memento from April 5, 2003 in the Internet Archive )

    literature

    • Gert Bloos, Gerd Dietl & Günter Schweigert: The Jura of Southern Germany in the Stratigraphic Table of Germany 2002. Newsletter on Stratigraphy, 41 (1-3): 263-277, Stuttgart 2005 ISSN  0078-0421

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