Holstein Warm Period

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system series step ≈  age  ( mya )
quaternary Holocene Meghalayum 0
⬍
0.012
Northgrippium
Greenlandium
Pleistocene Young Pleistocene
(Tarantium) 		0.012
⬍
0.126
Middle Pleistocene
(Ionian) 		0.126
⬍
0.781
Calabrium 0.781
⬍
1.806
Gelasium 1,806
⬍
2,588
deeper deeper deeper older

The Holstein warm period , or Holstein interglacial , in the Mindel-Riss interglacial Alpine region , is the penultimate major warm period (interglacial) before the Eem warm period and today's warm period, the Holocene . Within the Ice Age ( Pleistocene ) it lies in the section of the Middle Pleistocene .

definition

The Holstein interglacial is defined by marine sedimentation. The sequence of layers in the Sievertsche Ziegeleiton mine in Hamburg- Hummelsbüttel shows the development from the Elster Cold Age ( Lauenburg clay ) through the beginning warm period (freshwater deposits) to the flooding by the Holstein Sea (Cardien Sande).

Age determination

The exact age of the Holstein warm season is still the subject of controversy today. In the internationally accepted classification based on oxygen isotope stages ( engl .: based Oxygen Isotope Stage = OIS), the Quaternary geologists is from one part to be favored before the oxygen isotope stage (OIS) 11 while OIS stage 7 currently hardly is represented. The methods of age determination improved in the last 10 years, in particular uranium-thorium dating and radiofluorescence as a new method of thermoluminescence dating, make the oxygen isotope level 9.3 most likely for Central Europe. The Holstein interglacial began around 340,000 years ago and ended around 325,000 years ago. It followed the Elster Cold Age . The Holstein warm period was replaced by the Saale cold period and probably correlates with the Mindel-Riss interglacial in the Alpine region.

vegetation

Independent of lithostratigraphic definitions, palynology also describes an interglacial type Holstein. Typical of the pollen profiles of the Holstein interglacial is the dominance of coniferous forests with an initially high proportion of spruce ( Picea ), later enriched by a high proportion of fir ( Abies ). In addition, there are demanding (today sub-Mediterranean widespread) species such as boxwood ( Buxus ), wine ( Vitis ) and wingnut ( Pterocarya ). The immigration history of the vegetation communities differs significantly from that of other warm periods, such as the Eem interglacial and the Holocene .

literature

  • R. Hallik: The vegetation development of the Holstein warm period in northwest Germany and the age of the kieselguhr deposits of the southern Lüneburg Heath. In: Journal of the German Geological Society. 112, 1960, pp. 326-333.

Web links

Individual evidence

  1. ↑ E.-F. Grube: The importance of the Holstein interglacial outcrop of Hamburg-Hummelsbüttel for the geology of Northern Germany. In: Yearbook of the Alster Association. 1959, pp. 5-9.
  2. ↑ E.-F. Pit: Geology of the brickworks clay pits of Hamburg-Hummelsbüttel. In: Yearbook of the Alster Association. 42, 1963, pp. 25-30.
  3. ↑ F.-R. Averdieck: The Holstein interglacial from Hamburg-Hummelsbüttel. In: Meyniana. 44, 1992, pp. 1-13.
  4. ^ M. Dallek: Holstein interglacial deposits of Hamburg-Hummelsbüttel. In: Yearbook of the German Youth Association for Nature Observation. 2, 1963, pp. 136-147.
  5. ^ KL Knudsen: Foraminiferal Faunas in Marine Holsteinian Interglacial Deposits of Hamburg-Hummelsbüttel. In: Messages from the Geological-Paleontological Institute of the University of Hamburg. 49, 1979, pp. 193-214.
  6. ↑ MR Krbetschek, D. Degering, W. Alexowsky: Infrared Radiofluorescence Age (IR-RF) Sub -Saale-Age Sediments in Central and Eastern Germany. In: Journal of the German Society for Geosciences. Volume 159/1, 2008, pp. 141 ff.
  7. ↑ Mebus A. Geyh, Helmut Müller: Numerical 230 Th / U dating and palynological a review of the Holsteinian / Hoxnian interglacial. In: Quaternary Science Reviews. 24 (16-17), 2005, pp. 1861-1872. doi: 10.1016 / j.quascirev.2005.01.007