A new Early– Middle Weichselian palaeoenvironmental record from a lacustrine sequence at Svirkanciai, Lithuania

The M iddle W eichselian ( OIS 4‐3) and the transition from E arly to M iddle W eichselian are the most problematic and disputed time intervals of the L ate P leistocene with regard to the palaeogeography of the F ennoscandian glaciations. The number of sites with sediments of M iddle W eichselian a...

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Bibliographic Details
Published in:Boreas
Main Authors: Satkunas, Jonas, Grigiene, Alma, Buynevich, Ilya V., Taminskas, Julius
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2012
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Online Access:http://dx.doi.org/10.1111/j.1502-3885.2012.00280.x
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1502-3885.2012.00280.x
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1502-3885.2012.00280.x
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Summary:The M iddle W eichselian ( OIS 4‐3) and the transition from E arly to M iddle W eichselian are the most problematic and disputed time intervals of the L ate P leistocene with regard to the palaeogeography of the F ennoscandian glaciations. The number of sites with sediments of M iddle W eichselian age in the B altic region is very limited. An extensive area (77 km 2 ) of lacustrine sediments (sand, clay, silt with humus and interlayers of peat), under the relief‐forming U pper W eichselian till, was discovered in the vicinity of the V enta settlement, northwestern L ithuania, and named the V enta P alaeolacustrine B asin. The S virkanciai outcrop (56°18′05″ N , 22°53′00″ E ) (15 m in height) of this palaeobasin is composed of two sediment complexes of different genesis and age. The lower part consists of silt and very fine‐grained sand of lacustrine origin. According to palynological data, the lacustrine sediments accumulated under boreo‐arctic climatic conditions. The pollen records suggest that local vegetation was sparse forest with open areas. An Optically Stimulated Luminescence ( OSL ) date of the lacustrine sand yielded an age of >79±6 ka, which indicates that lacustrine conditions may have occurred during part of the E arly W eichselian O dderade I nterstadial ( J onionys 2). However, the palynological data from S virkanciai suggest a M iddle W eichselian age, possibly correlating with the O erel I nterstadial ( J onionys 3) 55 ka ago. No traces of early M iddle W eichselian S chalkholz ( N emunas 2a) stadial glacial advance have been found in the V enta sections. This also suggests a M iddle W eichselian age for the S virkanciai lacustrine sediments.