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Rapid sea-level rise during the first phase of the Littorina transgression in the western Baltic Sea

Stattegger Karl, Leszczyńska Karolina

Oceanologia

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2023

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Vol. 65 (1)

202--210

EN

Glacio-isostatic adjustment (GIA) corrected limiting non-marine and marine sea-level data from the western Baltic Sea indicate a rapid relative sea-level (RSL) rise of 18 m for the first phase of the Littorina transgression using a linear age-elevation model. This accelerated RSL rise occurred in the time period 8.57 to 8.0 ka before present (BP) with an RSL rise rate of 31.5 mm/year. RSL rose from 28 m to 10 m below the mean relative sea level (bmrsl) during the time period of less than 600 years. The first phase of Littorina transgression documents the last big meltwater pulse (MWP), which has been reported also from various other regions in the world as a consequence of the final decay of the Laurentide ice sheet and additional meltwater sources from Antarctica.

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The foraminiferal record in the Holocene evolution of the Mecklenburg Bay (south-western Baltic Sea)

Kostecki Robert, Radziejewska Teresa

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 2

169--183

EN

Foraminiferal assemblages were analyzed in a 620-cm long core retrieved from the central part of the Mecklenburg Bay (MB, south-western Baltic Sea) to aid in the reconstruction of environmental changes occurring in the area during the Holocene and to complement a set of previously investigated palaeoenvironmental proxies. A total of five foraminifera-based stratigraphic units were identified, including an initial 80-cm thick layer devoid of foraminifera. The next two units featured an increasing abundance of the foraminiferal assemblage dominated by the calcareous Ammonia group species. Nearly all the calcareous foraminifera found in the core were decalcified. Following the maximum abundance within the 470–410 cm layer, the foraminiferal abundance declined sharply and the assemblage’s dominance structure changed to domination of the agglutinated foraminiferal species, Eggerelloides scaber, which continued up to the top of the core and marked a pronounced shift in environmental conditions (shallower depth, lower salinity, more dynamic sedimentation conditions). The foraminifera-based stratigraphy of the core proved to be complementary to that emerging from previous analyses of diatoms and sediment geochemistry.

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Holocene evolution of the Pomeranian Bay environment, southern Baltic Sea

Kostecki R., Janczak-Kostecka B.

Oceanologia

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2011

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No. 53 (1-TI)

471-487

EN

This article focuses on the diatom assemblages and geochemical composition of sediment cores retrieved from the Pomeranian Bay. We also discuss similarities and differences in the diatom assemblages and the palaeogeographic development of nearby regions. Our main objective was to determine the characteristics and rate of the Littorina transgression in the Pomeranian Bay area. Sediments were divided into units based on differences in the distribution of diatom ecological groups and in geochemical ratios, such as Mg/Ca, Na/K and Fe/Mn. This study identified lacustrine sediments deposited during the time of the Ancylus Lake. This lacustrine-period sedimentation took place in a shallow lake under aerobic conditions. The record of the onset of marine environment dates to 8900-8300 cal BP and corresponds to the Littorina transgression. After about 8300 cal BP, sedimentation took place in a deeper marine environment with higher biogenic production and anaerobic conditions. The abrupt appearance of marine diatom species and increased geochemical salinity indicators reflect the large impact of the Littorina transgression on the Pomeranian Bay environment.

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Diatomological and geochemical evidence of littorina transgression in Pomeranian Bay, Southern Baltic Sea

Kostecki R., Janczak-Kostecka B.

Studia Quaternaria

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2010

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Vol. 27

27-33

EN

This article presents results of the analysis of 3 sediment cores taken from the bottom of Pomeranian Bay, southern Baltic Sea. These results are part of a larger project that aims to determine the characteristics and rate of the Atlantic marine ingression in the Pomeranian Bay area. The main geochemical elements and diatom assemblages from the cores were identified, revealing lacustrine sediments deposited during the time of Ancylus Lake and marine sediments deposited during the Littorina transgression. Distinct changes in the geochemical composition and diatom assemblages suggest that the Littorina transgression had a very large impact on the environment of Pomeranian Bay.

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Dating littorina sea shore levels in Denmark on the basis of data from a mesolithic coastal settlement on skagens odde, northern Jutland

Christensen Ch., Nielsen A. B.

Polish Geological Institute Special Papers

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2008

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Vol. 23

27-38

EN

The Mesolithic settlement site of Yderhede on Skagens Odde is interesting because it lies on Denmark’s highest Littorina coastline, 13 m above present-day sea level. The settlement was founded on peaty ground on the shore of a sheltered fjord. Pollen-analytical investigations have been carried out on marine/brackish gyttja deposits containing refuse from the settlement. These marine sediments were formed as a result of a transgression starting around 5300 cal. BC, reaching a maximum of 13 m above present sea level. Settlement took place during a subsequent regression and ceased in connection with a new Atlantic transgression. Subsequently, the lagoon silted up partly due to isostatic land upheaval of the area. The settlement lies on flat ground below the marked raised coastal cliff that runs from Frederikshavn to Hirtshals. The formation of this cliff has previously been assigned to the time of the Littorina Sea, but it is now suggested that it was formed in Late Glacial times. The two transgressions demonstrated here have been fitted into the overall pattern for sea-level change in Denmark. Subsequently, on the basis of well-dated sea-level curves for Southern Scandinavia, dates are given for the highest shore levels of the Littorina Sea. As a result of the interaction between increasing upheaval in a north-easterly direction and the general sea-level rise during the Littorina transgression, the maximum in the Gothenburg area (23 m isobase) occurs as early as 6300 cal. BC, whereas the maximum at the 0 m isobase in Southern Denmark first occurs around 3600 cal. BC.