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| Titel |
The Heidelberg Basin Drilling Project - Sedimentology and Stratigraphy of the Quaternary succession |
| VerfasserIn |
Dietrich Ellwanger, Gerald Gabriel, Jürgen Hahne, Christian Hoselmann, John Menzies, Theo Simon, Michael Weidenfeller, Ulrike Wielandt-Schuster |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250037618
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| Zusammenfassung |
| Within the context of the Heidelberg Basin Drilling Project (Gabriel et al. 2008), a detailed
sediment succession is presented here based upon deep drillings taken at Heidelberg UniNord
and Mannheim Käfertal. Sediment structures, and micromorphological and pollen analyses
were conducted and used to reconsider some of the climate transitions within the lower
Pleistocene. A new and novel scenario is postulated regarding the preservation of Quaternary
sediment packages within the Cenozoic Graben environment of the Heidelberg
basin.
The palynological evidence comprises the periods of warm climate of the Holsteinian (mainly
Abies (fir), some Fagus (beech), Pterocarya & Azolla); the Cromerian (Pinus-Picea-QM
(pine-spruce-QM)); the Bavelian (Abies, Tsuga (hemlock fir), QM & phases of
increased NAP including Pinus); the Waalian (Abies, Tsuga, QM); and the Tiglian
(Fagus & early Pleistocene taxa especially Sciadopytis, downward increasing Tertiary
taxa).
The sediment package was studied both macroscopically and microscopically. Both
techniques provide evidence of fluvial, lacustrine and mass movement sedimentary processes.
Some include evidence of periglacial processes (silt droplets within fine grained sands
indicative of frozen ground conditions). The periglacial structures are often, not always,
accompanied by pollen spectra dominated by pine and NAP.
E.g. the Tiglian part of the succession shows periglacial sediment structures at its base and
top but not in its middle sections. I.e. it appears not as a series of warm and cold phases but
rather as a constant warm period with warm-cold-alternations at its bottom and
top.
All results illustrate sediment preservation in the Heidelberg basin almost throughout the
Quaternary. This may be due to tectonic subsidence, but also to compaction by sediment
loading of underlying fine sediments (Oligocene to Quaternary) leading to incomplete but
virtually continuous sediment preservation (Tanner et al. 2009).
References
Gabriel, G., Ellwanger, D., Hoselmann, C. & Weidenfeller, M. (2008): The Heidelberg
Basin Drilling Project. – Eiszeitalter u. Gegenwart (Quaternary Science Journal), 57, 3-4,
253-260, Hannover.
Tanner, D.C., Martini, N., Buness, H. & Krawczyk, C.M. (2009): The 3D Geometry of
the Quaternary and Tertiary strata in the Heidelberg Basin, as defined by reflection seismics.
– DGG Tagung, Dresden, 30.9-02.10.09, Schriftenreihe der Deutschen Gesellschaft für
Geowissenschaften, 63, 58. |
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