The Jurassic of Germany

• Autorzy: Monnig E.
• Konferencja: International Congress on the Jurassic System (7 ; 06-18.09.2006 ; Kraków, Poland)
• Języki publikacji: EN

Abstrakty

EN

A geological map of Germany showing the distribution of Jurassic rocks is presented together with an updated and revised lithostratigrahic scheme for the Jurassic succession of this area. Geological map and important outcrops The Jurassic of Northern Germany crops out as a narrow band between the town of Osnabrück and the Harz Mountains. This visible part is only one percent, the other 99 percent lie in the subsurface and have an extension of over 100,000 km2. The Jurassic of Southern Germany is nearly half as large but much better exposed in the Swabian and Franconian Albs with very important fossil localities (Holzmaden, Solnhofen). Other areas are near Trier and in the Rhine Valley between Mannheim and Basel. The main subsurface data came from over 100,000 boreholes or shafts, which have sunk for the extensive exploitation of oil, gas, salt, iron ore, caverns/disposal sites, radioactive waste disposal or water. Borehole measurements, cores and drill cuttings provided an immense quantity of data as well as on about 500,000 km of reflection seismic lines of different quality. Stratigraphic Table The Jurassic lithostratigraphic scheme is based on the Stratigraphic Table of Germany 2002 (Mönning et. al. 2002). Here the Jurassic is represented by two abstracted and schematised cross sections from west to east. In contrast to this several troughs are considered in more detail. The Jurassic of Northern Germany is situated within the North German Depression representing the central part of the Middle European Depression. It is an area of long-term subsidence and sediment accumulation. From the Late Triassic the basin was subdivided into NW to WSW-ESE striking troughs and swells as a result of halokinetic movements. Where salt accumulated, it pushed upwards as diapirs, leading in the Middle Jurassic to widespread erosion. In southern Germany Jurassic deposits are less thick but more constant in facies development. The lithostratigraphic subdivision of the Jurassic deposits of southern Germany into Schwarzer Jura, Brauner Jura and Weißer Jura is undoubtedly fixed since Quenstedt (1843). The Norddeutscher Jura (Northern German Jurassic Super Group) does not exactly correspond to the Jurassic System and extends from the Hettangian to the Lower Berriasian. (Mönnig et al. 2002). Here the terms Lias, Dogger and Malm has been used since a long time as lithostratigrapic units leading to some confusion. For example the Malm-Gruppe (Gramann et al. 1997) does not correspond exactly with the Upper Jurassic Subsystem (Malm). It excludes the upper Ornaten-Ton Fm. (Lower Oxfordian) and includes the upper Münder Fm (Lower Berriasian). It is proposed to enclose the word Norddeutsche to the terms Lias-, Dogger- and Malm-Gruppe to emphasise the lithostratigraphic character. In connection with the revision of the existing lithostratigraphic nomenclature, sequence stratigraphic analysis is seen as valuable additional tool for a better understanding of the complex geological settings. Even though no detailed investigation has been done till today, it is clear that the marine Jurassic is represented by cyclically arranged mudstones, sandstones, limestones and ironstones and that sedimentation was strongly influenced by sea-level changes in combination with tectonic activities and salt movements. It was possible to subdivide the German Jurassic into 22 regressive-transgressive cycles.

Słowa kluczowe

EN

Jurassic; Germany; chart; lithostratigraphy; map; chronostratigraphy; sea level changes

• Wydawca: Państwowy Instytut Geologiczny - Państwowy Instytut Badawczy
• Czasopismo: Volumina Jurassica
• Rocznik: 2006
• Tom: Vol. 4, no. 1
• Strony: 192--193
• Opis fizyczny: Bibliogr. 3 poz.

Twórcy

autor

Monnig E.

• Naturkunde-Museum Coburg, Park 6, D-96450 Coburg,

Bibliografia

• Gramann F., Heunisch C., Klassen H., Kockel F., Katschorek T., Dulce G., Harms F.-J., Monnig E., Schudack M., Schudack U., Thies D. and Weis M. 1997. Das Niedersachsische Oberjura-Becken – Ergebnisse interdisziplinarer Zusammenarbeit. Zeitschrift der Deutschen Geologischen Gesellschaft, 148, 2: 165-236.
• Monnig E. (Coord.) and Subcommission. 2002. Jura. In: Deutsche Stratigraphische Kommission, (Ed.), Stratigraphische Tabelle von Deutschland 2002.
• Quenstedt F. A. 1843. Das Flozgebirge Wurttembergs. Mit besonderer Rucksicht auf den Jura. 58 pp. Tubingen, Laupp.