Mecklenburg phase

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Glacial /
interglacial 		  Stadiale /
Interstadiale   		 Period (BC) 
Vistula late glacial
Younger dryas period 10,730-9,700
Alleröd Interstadial 11,400-10,730
Older dryas period 11,590-11,400
Bölling-Interstadial 11,720-11,590
Oldest dryas period 11,850-11,720
Meiendorf-Interstadial 12,500-11,850
Vistula high glacial
Mecklenburg phase 15,000-13,000
Pomeranian phase 18,200-15,000
Lascaux-Interstadial 19,000-18,200
Laugerie-Interstadial 21,500-20,000
Frankfurt phase 22,000-20,000
Brandenburg phase 24,000-22,000
Tursac Interstadial 27,000-25,500
Maisières-Interstadial 30,500-29,500
Denekamp-Interstadial 34,000-30,500
Huneborg Stadium 39,400-34,000
Hengelo Interstadial 41,300-39,400
Moershoofd Interstadial 48,700
Glinde Interstadial 51,500
Ebersdorf Stadium 53,500
Oerel-Interstadial 57,700
Vistula early glacial
Schalkholz Stadium 60,000
Odderade Interstadial 74,000
Rederstall-Stadial ?
Brörup-Interstadial ?
Amersfoort-Interstadial ?
Herning Stadium 115,000
Eem warm period
126,000

The last ice advance of the Scandinavian inland ice at the end of the pleniglacial of the Vistula glaciation is known as the Mecklenburg phase . It dates roughly to the period 15,000 to 13,000 BC. Chr.

Naming and conceptual history

The term Mecklenburg-Phase, also known as the Mecklenburg-Stadium , Mecklenburg-Vorschlag or Jungbaltischer Gletschervorschlag , goes back to Archibald Geikie , who in 1895 cited a Mecklenburgian in his classification of the Pleistocene , which was to characterize the terminal and bottom moraines of the last Baltic ice flow. K. Keilhack's Mecklenburg level from 1896 was unfortunately a misallocation to the terminal moraines of the Frankfurt phase . It was not until 1965 that S. Heerdt realized that after the Pomeranian phase another ice advance had occurred, which had left its own ground moraine in the north of Mecklenburg - correlated with the Rosenthaler Staffel , a terminal moraine. In 1984, J. Eiermann redefined the Mecklenburg Stadium .

The type region of the Mecklenburg phase is the northern state of Mecklenburg; there is no separate type locality .

Geographical course

The Mecklenburg phase is mainly present as a ground moraine in the north of Mecklenburg. Only in places, such as in the Rosenthaler Staffel , is the ice advance marked by terminal moraines. In western Mecklenburg it comes close to the Pomeranian main terminal moraine ( W2 ) of the previous Pomeranian phase and follows it to the east. Only in Western Pomerania does it stand out more clearly. Further to the east it connects to the Szczecin relay and is also said to be traceable to Masuria with several interruptions . Its continuation to the west and north-west is not certain, but it is very likely to run over the innermost edge of the Lübeck Bay , to Schleswig-Holstein over the Sehberg edge and finally to Denmark over the East Jutian edge .

In Schleswig-Holstein and Denmark there was then a further advance, which lagged behind the first. In Schleswig-Holstein it is referred to as the Warleberg advance and in Denmark as the Beltsee advance . The Beltsee advance crosses the Flensburg Fjord , the island of Fyn in Denmark and then follows a line that runs north of the Great Belt and the island of Zealand .

The ice edge of the last active phase lies along the Darsser Schwelle between North Mecklenburg and Falster , it then turns north, circumscribes the Fakse Bugt and the Køge Bugt Zealand, crosses the south of the Öresund and finally runs through the most south-western part of Skåne . It possibly correlates with the Velgaster outskirts .

Stratigraphy and Correlation

The Mecklenburg phase, indicated on geological maps with W3 or qW3 , stratigraphically follows the Pomerania phase. In turn, it will be replaced by the Meiendorf Interstadial of the Vistula Late Glacial. It correlates with the Greenland stage 2a ( GS-2a ). In the Mecklenburg-Western Pomerania type region it can be divided into three parts (from young to old):

  • Northeast Rügen outskirts W3Rü
  • Velgaster outskirts W3V
  • Mecklenburg-Rosenthal outskirts W3 / W3R

The continuation of the Mecklenburg-Rosenthaler outskirts to the west (Schleswig-Holstein) is not clear and a correlation with the Sehberg advance ( qw5 ) is controversial, Müller u. a. (1995) rather connect this advance with the Pomeranian phase. However, a correlation with the Warleberg or Fehmarn advance ( qw6 ) is more likely. As already mentioned, the Velgaster outskirts may continue over the Darsser Schwelle to Denmark. Overall, the Mecklenburg phase can be assigned to the Polish Gardno Stadium (or Gardno Phase).

Dating

Thermoluminescence data on kame sediments from the Bay of Lübeck have an average age of 13,000 BC. Delivered. Görsdorf and Kaiser (2001), on the other hand, give a rather old age of 14,060 ± 220 carbon years vh for the demarcation of the Vistula late glacial; when calibrated, this corresponds to 15,356 v. BC (15,526 to 15,110 BC). The first warming of the Late Mozzy Period (transition from the pleniglacial to the Meiendorf interstadial ) is 12,700 BC. Dated. Similarly, Lowe et al. a. (2008) the beginning of the Late Glacial with 12,692 BC. Chr. Litt u. a. (2007), however, define the end of the Vistula high glacial a little later with 12,500 BC. Overall, the previous cooling during the Mecklenburg phase is likely to be in the period from 15,000 to 13,000 BC. To be asked.

geology

For the state of Mecklenburg-Western Pomerania , the arrangement of the ice edge layers of the Vistula high glacial shows a chronological sequence that shows an age decreasing from southwest to northeast. For example, the W1B peripheral location of the Brandenburg phase, which moves from Schwerin to the southeast, is roughly paralleled by the peripheral location of the Frankfurt W1F phase only a few kilometers away . Morphologically the most outstanding element is the Pomeranian main ice edge layer W2 of the two-part Pomeranian phase with an approximate age of 15,600 years BC , which is divided into praises . The Pomeranian main ice-edge location begins east of Lübeck , goes around the south of Wismar , then turns in a south-easterly direction and passes 20 kilometers south of Neubrandenburg . Its associated ground moraine is extensive in the north-eastern backland and is also widespread in greater thicknesses, except for channel and basin areas. The landscape of Western Pomerania, which adjoins it to the north and is dominated by ground moraines, is counted among the flat, undulating north Mecklenburg clay plates , in which the edge of the inland ice, which was contiguous during the main Pomeranian advance, dissolved or subsequently oscillated due to climatic fluctuations. The maximum advance of the Pomeranian phase runs parallel to the main marginal line and is only a few kilometers in front of it to the southwest; However, when it reaches the Warnow, it turns to the west in the direction of Schwerin and there approaches the edge of the Frankfurt phase.

Following the Pomeranian Haupteisrandlage Rosenthaler outskirts W3R of Mecklenburg-phase with their model-like edging walls and individual Sander distributions. The W3R or W3 terminal moraine begins in the east on the border with Poland near Pampow / Mewegen and continues to the west via the Pasewalker Kirchenforst . In the terminal moraine complex of the Brohmer Mountains (up to 148 m above sea level) between Jatznick and Wittenborn with the type locality Rosenthal, the W3R edge reaches its most distinctive expression and becomes morphologically inconspicuous as it continues to the west. To the north of the Rosenthaler outskirts, the near-surface W2 ground moraine is characterized by a mostly thin and sandy till with a characteristic lithological composition, which can be assigned to a W3 advance. The predominantly low-relief ground moraine plains in the rear of the W3R outskirts are characterized in Western Pomerania by morphologically rather inconspicuous retreats as well as valleys and wide basins, such as B. the Haffstausee basin , further subdivided. The Velgaster peripheral location W3V , which runs west from Stralsund via Wolgast to Usedom , has the character of a compression moraine over longer stretches. The Velgaster outskirts may be continued over the Darsser Schwelle to Funen. A terminal moraine that is controversial in terms of its status and course is the so-called Spantekower peripheral location . This only locally mapped W3 retreat relay appears morphologically in the Hellberge area near Drewelow .

Ice flow

An evaluation of regulated and scribbled debris, glacier scrapes and other structural data shows that during the Mecklenburg phase the ice masses of the Scandinavian ice sheet penetrated from the area of ​​today's eastern Baltic Sea between southern Sweden and the southern Baltic coast far to the west and spread out in a fan shape in the western Baltic region . However, their spatial expansion lagged behind the previous Pomeranian phase. The eastern origin of the ice flow is evidenced by the composition of the glacial material transported. For example, the W3 ground moraine material contains relatively high proportions of paleozoic limestone ( Gotland ) and red, early Cambrian sandstones ( Bornholm ). It is likely that the advance to the west was made possible by the rather rapid melting of the previously blocking ice centers in Norway and Sweden. The movement of the Eisstromes carried out may very rapidly and abruptly ( engl. Surge ) due to water supersaturated sediment, a thin film of water at the base or by a loss of contact to the base.

Environmental parameters

Oxygen isotopes

During the Mecklenburg phase the δ 18 values fluctuated between -42 and -39 ‰ SMOW around an average value of -40.5 ‰ SMOW. They were thus more than 5 ‰ lower than at the beginning of the Meiendorf interstadial. Compared to the previous Pomeranian phase, they were almost 3 ‰ lower.

Temperatures

According to Renssen and Isarin (2001), the winter temperatures in the Mecklenburg phase were up to 20 ° C lower than in the late glacial Meiendorf interstadial; they are likely to have ranged between -25 and -15 ° C. The summer temperatures were only slightly cooler at 10 to 15 ° C compared to 13 to 17 ° C.

Cultural history

Towards the end of the Mecklenburg phase, the Upper Paleolithic Hamburg culture emerged in northern Germany (13,500 to 11,100 BC), which was mainly based on reindeer hunting. Southern Germany belonged to the culture of the Middle Magdalenian .

See also

Individual evidence

  1. ↑ Thomas Litt, Achim Brauer , Tomasz Goslar, Josef Merkt, Krystyna Bałaga, Helmut Müller, Magdalena Ralska-Jasiewiczowa, Martina Stebich, Jörg FW Negendank: Correlation and synchronization of Lateglacial continental sequences in northern central Europe based on annually laminated lacustrine sediments. In: Quarternary Science Reviews. vol. 20, No. 11, May 2001, pp. 1233-1249.
  2. ↑ For the sake of standardization, the age data for the climatic stages of the Vistula Late Glacial were converted to v. With the dendrochronological and warven chronological data, the reference point is the year 1950, ie 1950 years have to be subtracted to get BC. Chr. Indications to receive. The ice core data, on the other hand, relate to the reference year 2000. The age information from the Vistula high glacial is the approximate start of the corresponding time interval vh
  3. ↑ a b Litt, T. u. a .: Stratigraphic terms for the Quaternary of the north German glaciation area . In: Ice Age and the Present / Quaternary Science Journal . tape 56 1/2 , 2007, p. 7-65 ( online ). online ( Memento of the original from February 5, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / quaternary-science.publiss.net
  4. ↑ Heerdt, S .: On the stratigraphy of the Young Pleistocene in central N-Mecklenburg . In: Geology . tape 14 (5/6) , 1965, pp. 589-609 .
  5. ↑ Eiermann, J .: A temporal, spatial and genetic model to explain the sediments and relief forms in the Pleistocene glacier-covered lowland sediments - A contribution to the methodology of the mediocre natural spatial structure . Ed .: H. Richter and K. Aurada Umweltforschung. To analyze and diagnose the landscape. H. Haack, Gotha 1984, p. 169-183 .
  6. ↑ Smed, P .: Stones from the north: sediments as witnesses of the ice age in northern Germany . Borntraeger, Berlin 1994.
  7. ↑ Müller, U. u. a .: The Pleistocene sequence in Mecklenburg-Western Pomerania . Ed .: Ehlers, J., Kozarski, S. & Gibbard, P .: Glacial deposits of North-East Europe. Rotterdam (Brookfield: Balkema) 1995, p. 626 .
  8. ↑ Mojski, J .: Pleistocene glacial events in Poland . Ed .: Ehlers, J., Kozarski, S, & Gibbard, P .: Glacial deposits in North-East Europe. Rotterdam 1995, p. 287-292 .
  9. ↑ Görsdorf, J. & Kaiser, K .: Radiocarbon data from the Late Pleistocene and Early Holocene of Mecklenburg-Western Pomerania . In: Meyniana . tape 53 . Kiel 200, p. 91-118 .
  10. ↑ Lowe, JJ and a .: Synchronization of palaeoenvironmental events in the North Atlantic region during the Last Termination: a revised protocol recommended by the INTIMATE group . In: Quaternary Science Reviews . tape 27 (1–2) , 2008, pp. 6-17 .
  11. ↑ Börner, A. u. a .: Geoscientific investigations on the OPAL route in Mecklenburg-Western Pomerania - field work and first results . In: Brandenburg. geowiss. Contribution Volume 18, 1/2 . Cottbus 2011, p. 9-28 .
  12. ^ Hurtig, T .: Physical geography of Mecklenburg . Berlin 1957, p. 252 .
  13. ↑ Bremer, F .: Glacial Morphology . Ed .: Katzung, G .: Geology of Mecklenburg-Western Pomerania. E. Schweizerbart, Stuttgart 2004, p. 284-291 .
  14. ↑ Schulz, W .: The compression moraine of the Rosenthaler Staffel between Jatznick and Brohm in Mecklenburg and their relationship with the Helpter Berg . In: Geology . tape 14, 5/6 . Berlin 1965, p. 564-588 .
  15. ↑ Rühberg, N .: The ground moraine of the most recent Vistula advance in the GDR region . In: Z. geol. Knowledge tape 15, 6 . Berlin 1987, p. 759-767 .
  16. ↑ Krienke, H.-D .: Map of the Quaternary Formations - surface up to five meters deep, 1: 200,000, sheet Neubrandenburg / Torgelow . Ed .: Geological State Office Mecklenburg-Western Pomerania. Schwerin 2001.
  17. ↑ Stephan, H.-J .: The Young Baltic Glacier Advance in Northern Germany . In: Schr. Naturwiss. Ver. Schleswig-Holst. tape 64 , 1994, pp. 1-15 .
  18. ↑ Boulton, GS and Jones, AS: Stability of temperate ice caps and ice sheets resting on beds of deformable sediment . In: J. Glaciol . tape 24 , 1979, pp. 29-43 .
  19. ↑ Piotrowski, JA and Tulaczyk, S .: Ice-bed separation and enhanced basal sliding under the last ice sheet in north-west Germany? In: Quatern. Sc. Rev. Band 18 , 1999, p. 737-751 .
  20. ^ Stephan, H.-J .: The Young Baltic advance in the western Baltic depression . In: Geological Quarterly . tape 45 (4) , 2001, p. 359-363 .
  21. ↑ Björck, S. u. a .: An event stratigraphy for the Last Termination in the North Atlantic region based on the Greenland ice-core record: a proposal by the INTIMATE group . In: Journal of Quaternary Science . tape 13 . New York 1998, pp. 283-292 .
  22. ↑ Renssen, H. and Isarin, RFB: The two major warming phases of the last deglaciation at similar to 14.7 and similar to 11.5 ka cal BP in Europe: climate reconstructions and AGCM experiments . In: Global and Planetary Change . tape 3 (1-2) , 2001, pp. 117-153 .