Bölling-Interstadial

Series / ( Glacial )	Climatic levels	Period v. Chr.
Holocene
Holocene	Preboreal	9,610-8,690
Pleistocene ( Vistula - Late Glacial )
	Younger dryas period	10,730-9,700 ± 99
	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 )
( Vistula - high glacial )	Mecklenburg phase

The Bölling-Interstadial , also Bølling-Interstadial , is a relatively warm period in the history of the earth in the last phase of the Vistula glacial period ( Quaternary ). It followed the cool period of the Elders Dryas and was replaced by the also quite cool period of the Older Dryas . According to varven years , the Bölling interstadial lasted from 13,670 varven years vh to 13,540 varven years vh. This is the period from 11,720 to 11,590 BC. It is characterized in Central Europe by a birch forest.

Naming and conceptual history

The name was introduced into scientific literature by Johannes Iversen in 1942 as the Bölling oscillation or Bölling period . It is named after the Bølling Sø ( Jutland , Denmark ).

definition

The lower limit of the Bölling Interstadial is defined at its type locality at Bølling Sø by a marked increase in birch pollen (especially from tree birch) and a significant decrease in pollen from sea buckthorns ( Hippophaë ). The upper limit is characterized by a renewed decline in tree pollen and an increase in non-tree pollen.

Stratigraphy and Correlation

In Northern Germany , the Bölling-Interstadial follows the Oldest Dryas Period or the Aegelsee fluctuation, and is completed by the Older Dryas Period . It thus corresponds to the Greenland Interstadial 1c3 ( GI-1c3 ), the end of the three-part Greenland Interstadial 1c . In contrast to this, in southern Germany , in Switzerland , in North America and in the North Atlantic area, the period between the pleniglacial and the oldest Dryas is viewed as Bölling-Interstadial, corresponding to the period GI-1e . In Northern Germany, however, this is equivalent to the Meiendorf Interstadial . In Norway the Bølling oscillation starts immediately after the Pleniglacial (here Oldest Dryas) and lasts until the older Dryas I, interrupted by the two cold stages BCP I ( engl. Bölling Cold Phase I ) and BCP II ( Bölling Cold Phase II , and referred to as IBCP and equivalent to the Aegelsee fluctuation).

According to Hoek (1997), the Bölling interstadial in the narrower sense corresponds to pollen zone 2a1 , but the extended Bölling interstadial corresponds to pollen zone 1b .

Dating

After varven years in the Meerfelder Maar , the Bölling-Interstadial lasted from 13,670 varven years vh to 13,540 varven years vh, this corresponds to the period 11720 to 11590 BC. Chr. According to the Geozentrum Hannover contrast, it took 13,730 to 13,480 cal. Vh or from 11,780 to 11,530 v. Chr. Lowe et al. (2008) set the beginning as early as 11954 BC. On and according to van Raden et al. (2012) the Bölling-Interstadial lasted from 11958 to 11674 BC. Chr.

For the extended Bölling-Interstadial, van Raden use the period 12640 to 12094 BC. Chr.

Volcanic eruption

Around 13,600 ± 1,000 years BP, a volcanic eruption occurred at Puy Montchier in the Chaîne des Puys of the French massif Central .

Environmental parameters

Oxygen isotopes

Based on the NGRIP ice core, the Bölling-Interstadial is characterized by up to 2 ‰ increased δ ¹⁸ O values compared to the two cold phases , which oscillate between -38 and -39 ‰ SMOW (VPDB). The extended Bölling-Interstadial had its maximum value with -36% VPDB right at the beginning and then shows a steady decrease in the further course to -38 ‰ VPDB.

Temperatures

Using Coleoptera, Atkinson et al. (1987) determined annual average temperatures of 3 to 5 ° C for Great Britain during the Bölling Interstadial. The previous extended Bölling-Interstadial was even warmer, up to 7 ° C was already reached at the beginning. It was thus the warmest section of the late glacial with an enormous and very rapid temperature increase of over 10 ° C compared to the conditions in the pleniglacial. In the Netherlands , Heiri et al. (2007 ) determined summer temperatures (July) using Chironomidae . They showed slightly oscillating values of around 16.5 ° C for the Bölling interstadial and an increase from 14 to 17 ° C for the extended interstadial.

Sea level

Measurements on coral reefs in Barbados Peltier & Fairbanks (2006) refer to the Bølling oscillation at a sea level by 70 feet below sea level with a slightly rising trend. During the Meiendorf interstadial it was still between 93 and 90 meters below sea level.

Vegetation development

What is striking about the Bölling-Interstadial compared to the previous Elder Dryas is the sudden increase in tree pollen (to over 80%), thanks above all to the birch trees (with a total of 60%). Willows and junipers experienced a decline, but the latter was able to maintain its importance and, like a bush, penetrate the still relatively open birch forest. Heliophilic herbs such as ribwort and helianthemum lost their previous position. Also grasses , Cyperaceae , and the taxa sea buckthorn and Artemisia , fell sharply. Towards the end of the interstadial there was a decline in the proportion of birch trees in favor of the pine (up to 15%).

In the extended Bölling Interstadial, tree pollen had for the first time reached over 50% of the total pollen, mainly borne by birch trees, especially dwarf birch trees ( Betula nana ). After colonization by dwarf birch trees, the predominantly open grassy landscape of the pleniglacial was visibly interspersed with birch stands, which developed into sparse birch forests.

Cultural history

In the Levant , the Natufien (12300 to 10200 BC) developed during the Bölling Interstadial . This proto-agrarian culture level was based on the use of wild cereals such as emmer and double-row barley . In Central Europe , foothills of the Paleolithic were still to be found, so in the Parisian area the Magdalenian (16000 to 8000 BC) and in Italy and Eastern Europe the Epigravettia . Further north, the Hamburg culture (13500 to 11100 BC), the penknife groups (12000 to 10800 BC), the Tjonger group in the Netherlands and the Creswellia (12500 to 8000 BC) developed. in England and Wales .

swell

literature

Thomas Litt, Karl-Ernst Behre, Klaus-Dieter Meyer , Hans-Jürgen Stephan and Stefan Wansa: Stratigraphic terms for the Quaternary of the northern German glaciation area . In: T. Litt on behalf of the German Stratigraphic Commission (ed.): Stratigraphie von Deutschland - Quaternary. Special issue. Ice Age and Present / Quaternary Science Journal . 56, No. 1/2. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), 2007, ISSN 0424-7116 , p. 7-65 , doi : 10.3285 / e.g. 56.1-2.02 .

Individual evidence

↑ ^a ^b van Raden, UJ et al .: High-resolution late-glacial chronology for the Gerzensee lake record (Switzerland): δ18O correlation between a Gerzensee-stack and NGRIP . In: Palaeogeography, Palaeoclimatology, Palaeoecology . 2012.

↑ Hoek, WZ: Atlas to Palaeogeography of Lateglacial Vegetations - Maps of Lateglacial and Early Holocene landscape and vegetation in The Netherlands, with an extensive review of available palynological data . In: Netherlands Geographical Studies . tape 231 . Utrecht 1997.

↑ The Quaternary in Lower Saxony and neighboring areas (PDF) ( Memento of the original from January 14, 2016 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@ 2
^ Lowe, JJ et al .: 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 .
^ Miallier, D .: L'éruption phréatomagmatique du Montchié, Chaîne des Puys, Massif Central français (13.6 ± 1.0 ka) . In: Quaternaire . tape 24 (2) , 2013, pp. 99-107 .
↑ NGRIP dating group: Greenland Ice Core Chronology 2005 (GICC05), IGBP PAGES / World Data Center for Paleoclimatology, Data Contribution Series # 2006–118 . Ed .: NOAA / NCDC Paleoclimatology Program. Boulder CO, USA 2006.
↑ Atkinson, TC et al. a .: Seasonal temperatures in Britain during the past 22,000 years, reconstructed using beetle remains . In: Nature . tape 325 , 1987, pp. 587-593 .
↑ Heiri, O. et al .: Lateglacial summer temperatures in the Northwest European lowlands: a chironomid record from Hijkermeer, the Netherlands . In: Quaternary Science Reviews . tape 26 , 2007, p. 2420-2437 .
↑ Peltier, WR and RG Fairbanks, RG: Global ice volume and Last Glacial Maximum duration from an extended Barbados sea-level record . In: Quaternary Science Revue . 2006.
^ Van Geel, B. et al .: Palaeoecology and stratigraphy of the Lateglacial type section at Usselo (The Netherlands) . In: Review of Palaeobotany and Palynology . tape 39 , 1989, pp. 25-129 .

[van_Raden-1] van Raden, UJ et al .: High-resolution late-glacial chronology for the Gerzensee lake record (Switzerland): δ18O correlation between a Gerzensee-stack and NGRIP . In: Palaeogeography, Palaeoclimatology, Palaeoecology . 2012.

[2] Hoek, WZ: Atlas to Palaeogeography of Lateglacial Vegetations - Maps of Lateglacial and Early Holocene landscape and vegetation in The Netherlands, with an extensive review of available palynological data . In: Netherlands Geographical Studies . tape 231 . Utrecht 1997.