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1

Late Pleistocene and Holocene environmental evolution of the Wkra River Valley near Bielawy Gołuskie (central Poland) recorded in palaeo-oxbow lake deposits

Niska M., Jonczak J., Gadziszewska J.

Geological Quarterly

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2017

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Vol. 61, No. 2

305--318

EN

This study aimed to reconstruct environmental changes in the Wkra River Valley near Bielawy Gołuskie (central Poland) based on geochemical, palynological and subfossil Cladocera analysis of deposits filling a palaeo-oxbow lake. Two sediment boreholes collected from the palaeochannel bend (BG-1) and neck (BG-2) include full sequences of organic deposits lying on clastic deposits. The lower part of the BG-1 borehole contains gyttja that accumulated during the Younger Dryas and the Preboreal, which is covered by reed peat of Preboreal and Boreal age. On top of this is alder peat that accumulated during the Atlantic. The ages of the gyttja and peat were confirmed by both radiocarbon dating and palynological analysis. The peats are characterized by a significant content of organic matter, which is relatively stable over time. This indicates a low intensity of mechanical denudation in the catchment, which is supported by low concentrations of aluminum and potassium. Calcium values greatly exceed these elements, suggesting that the lake was mainly fed by groundwater. Variation in trophic conditions over time is indicated by a vertical variability in the content of nitrogen, as well as by the Cladocera population. The strong decomposition of peat in the top layer of the mire, and increased concentrations of phosphorus and heavy metals, testify to increasing human activity during the most recent time periods.

2

Early Holocene alluvia in the lower Wisłok River valley and their chronostratigraphy in the light of radiocarbon datings and palynological analysis

Superson S., Gębica P., Michczyński A., Kołaczek P., Szczepanek K.

Geochronometria

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2017

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Vol. 44, no. 1

216--225

EN

The paper presents the results of the latest radiocarbon dating and the palynological analyses of organic sediments found in the alluvia of the Wisłok River valley between the towns of Łańcut and Przeworsk. The study conducted in the gravel pit made possible the dating of several alluvial fills of the 7–8 m high Holocene terrace and the 5–6 m high floodplain. The oldest channel alluvia and palaeochannel sediments of the 7–8 m high terrace were dated at 10 100–9300 BP (11 960–10 500 cal BP). According to the anthracological analysis the top cover of clay overbank alluvia, which bears charcoal fragments, was deposited in the Subboreal and/or the Subatlantic Phases. In the sequence of the 5–6 m high floodplain, the bottom fills of palaeochannels, dated at 10 195–9885 cal BP (probability level: 68.2%; GdS-3233: 8900 ± 95 BP ) and 11 095–10 755 cal BP (probability level: 68.2%; GdS-3228: 9575 ± 95 BP), were truncated by erosion and covered by alluvia of palaeomeanders, which were active in the 19th century. Preservation of the erosional bench of the Early Holocene organic sediments indicates the predomination of lateral migration of the river channel during the last 200 years and the formation of wide erosional floodplain that has been aggraded with recent flood alluvia. In the 20th century the floodplain aggradation was simultaneous with the deepening of the Wisłok riverbed.

3

Palynology and archaeology of Late Vistulian and Early Holocene sites in Lubuskie Lake District, western Poland

Okuniewska-Nowaczyk I, Sobkowiak-Tabaka I

Studia Quaternaria

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2014

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Vol. 31, Nr 1

39--50

EN

The Lubuskie Lake District played an important part in recolonisation of the Polish Plain due to its location and the character of the terrain. Despite that, it is and especially its northern part, poorly explored regarding both history of Late Glacial and early Holocene settlements, and the natural environment. The paper presents results of multidisciplinary research in this area. The most spectacular discoveries were connected with remains of settlements of the Hamburgian culture societies at Myszęcin currently the richest site of this culture over the entire North European Plain. In the vicinity of this site several Late Palaeolithic and Mesolithic settlements of varied functions were recorded. First palynological records came from the Younger Dryas sediments in this area. In a log with a palynological spectrum comprising Younger Dryas and the beginning of the Holocene, a charcoal dust was found and it could indicate human activity as humans lived at a lake shore. An important complement to the image of the Late Glacial settlement at the Lubuskie Lake District was provided by the research near Lubrza that resulted in data regarding settlements of the Federmesser and Swiderian culture societies. This region was not typical in a palynological spectrum of deposits during Allerod but also indicated highly diversified thickness of basal peat in a small area.

4

Mesolithic occupations and environments on the Island of Ikaria, Aegean, Greece

Sampson A., Kaczanowska M., Kozłowski J. K., Athanassas C., Bassiakos Y., Liritzis I., Laskaris N., Tsermegas I.

Folia Quaternaria

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2012

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nr 80

1--87

EN

The most important Mesolithic site on the Island of Ikaria, Kerame 1, extends 80 m along the sloping edge of the cliff and is up to 40 m wide. The site is a sum of repeated sojourns of Mesolithic groups that had left behind concentrations of lithic artefacts, which were subsequently displaced by post-depositional agents, first of all by erosion. As a result, the site reveals now a large concentration of finds in Trenches E, C, and G. Moreover, post-depositional agents caused the destruction of permanent features such as the hearths associated with the various khsemenitsas, or — possibly — stone rings surrounding the dwelling structures. Only in trenches D, B and E the remains of a circular stone rings, probably around hearths, were registered. The lithic industry of Kerame 1 displays considerable similarity to the site of Maroulas on Kythnos; the techno-morphological differences are, probably, the effect of differing raw materials structure at Kerame 1 and at Maroulas. At Kerame 1, the distant interregional contacts and the influx of extralocal raw materials (documented by the flow of obsidian nodules from Melos and Yali) caused that production in a full cycle was carried out on-site. Thus, there was no specialization of lithic production, and unworked nodules of raw material were exploited in the particular social clusters in a full cycle, whose outcome were tools to be used by a given unit. Regretfully, because organic materials (also bones) have not been preserved we have no data to determine seasonality at Kerame l. Nevertheless, we can say with all certainty that Mesolithic groups visiting Kerame 1 were mobile, which is evidenced by the network of interregional contacts. The most noticeable similarity between Kerame 1 and Maroulas can be accounted for by the chronological closeness of the two sites. The AMS determinations from Maroulas concentrate in the first half of the 9th millenium cal. BC (Facorellis et a1. 2010). Similarly, the dates from obsidian dehydration from Kerame 1 (if their broad standard deviation is overlooked) correspond to the first half of the 9th millenium cal. BC.

5

Malakofauna osadów jeziornych torfowiska Gajlik na Pojezierzu Sejneńskim (północno-wschodnia Polska)

Alexandrowicz W. P., Żurek S.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2010

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T. 36, z. 4

491-504

PL

Analizie malakologicznej poddano skorupki ślimaków i małży występujące w gytiach wapiennych i kredach jeziornych wypełniających torfowisko Gajlik na Pojezierzu Sejneńskim. W sześciu analizowanych próbkach stwierdzono występowanie 13 gatunków mięczaków wodnych. Obserwowane zmiany składu i struktury zespołu mięczaków uzupełnione wynikami analiz palinologicznych i radiometrycznych pozwoliły na rekonstrukcję ewolucji torfowiska Gajlik w okresie późnego glacjału i dolnego holocenu. Skorupki mięczaków występowały wyłącznie w osadach związanych z cieplejszym i okresami (interfaza alleröd oraz preborealna i borealna faza holocenu). Nie pojawiały się one natomiast w osadach zimnych okresów późnego glacjału.

EN

Malacological analysis was conducted on snails and bivalve shells present in calcareous gytia and lacustrine chalk of the Gajlik mire in the Sejny Lake District. Thirteen species of water molluscs were identified within six analyzed samples. Changes observed in the structure and composition of molluscs, supplemented by palynological data, and the results of radiocarbon datings allowed for the reconstruction of the mire's evolution during Late Glacial and Early Holocene period. Molluscs' shells occurred solely in sediments associated with warmer periods (interphase Alleröd and Preboreal-Boreal phases of Holocene). Additionally, they were not present in sediments associated with cold Late Glacial periods.

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[Delta^18]O and [delta^13]C isotope investigation of the Late Glacial and early Holocene biogenic carbonates from the Lake Lednica sediments, western Poland

Apolinarska K.

Acta Geologica Polonica

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2009

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Vol. 59, no. 1

111-121

EN

Stable isotope composition ([delta^18]O and [delta^13]C) of biogenic carbonates derived from the Lake Lednica sediments at Rybitwy, western Poland, was applied to obtain data on climatic changes during the Late Glacial and early Holocene. A wide range of carbonates occurring in the sediments was analysed for [delta^18]O and [delta^13]C records, including shells of several gastropod species, the bivalve genus Pisidium and carapaces of ostracods belonging to the subfamily Candoninae. The [delta^18]O and [delta^13]C records reveal changes commonly observed for the Late Glacial and early Holocene with the exception of the low oxygen isotope values of the Bolling and Allerod Interstadials. The latter is interpreted as a consequence of [^18]O-depletion of the lake water resulting from gradual melting of the dead ice that still filled the deepest parts of the Lake Lednica valley during the period described. The Younger Dryas Stadial begins with the isotopically lightest values in the sequence; however, due to the [^18]O-depleted values of the Allerod Interstadial the Allerod/Younger Dryas boundary is poorly marked. The Younger Dryas/Preboreal transition is documented by a significant shift in [delta^18]O values of about 2-3[per mil], resulting from an increase in the mean annual temperature. The [delta^13]C record reflects the productivity level in the lake, with [^13]C-enriched carbonates during the Bolling and Allerod Interstadials, and the Preboreal and Boreal, when photosynthetic activity of phytoplankton and macrophytes was the most intensive. Differences in [delta^18]O and [delta^13]C values between mollusc shells and ostracod carapaces reflect the specific season and subhabitat of each carbonate secretion.

7

Evolution of the River Rega valley near Łobez in Late Pleistocene and Early Holocene

Cedro B.

Geochronometria

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2007

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Vol. 28

55-59

EN

The River Rega valley near Łobez was formed by a rapid icesheet degradation. Evolution of valleys of rivers (including the Rega) discharging into the Baltic Sea began in late Plenivistulian; it was then that glacifluvial outwash levels and kame terraces were formed. At that time, the water was flowing southward and further on towards the south-west, in a broad channel. That period was terminated at the turn of Plenivistulian and late Vistulian, when the discharge became directed northwards. The net result was the onset of the formation of the modern Rega valley system, buried chunks of dead ice still in the process of melting. Dead ice melt-down proceeded at the fastest rate during Allerod. It was then that deposits of organic matter were formed, the deposits being most probably remnants of fossil soil. Plant macro-fossils and remains of freshwater malacofauna point to a sporadic occurrence of sediments of a shallow water body which existed on the melt-down site of a huge chunk of dead ice. The thickness of the overlaying mineral cover (up to 6 m) is indicative of a fast sediment accretion rate. Sandy and silty sediments were deposited in synchrony with the dead ice melting. As a result, today’s Rega valley features traces of small melt-water lakes as well as fossil sedimentation basins (underlain by the Allerod organic level), rapidly filled with fluvial and fluviolimnic sediments. Since the Preboreal, the Rega has been flowing along a meandering channel.

8

Terrestrial deposits from the Słupsk bank as an evidence of the late glacial and early holocene Baltic sea level

Uścinowicz Sz., Zachowicz J.

Polish Geological Institute Special Papers

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2005

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Vol. 16

133--141

EN

The site of Late Glacial and Early Holocene peat and limnic sediments at eastern part of Słupsk Bank were investigated by seismoacoustic profiling, lithological, pollen and molluscs analyses, and 14C datings of 3 sediments cores. There is an evidence that from the last deglaciation to the beginning of the Littorina transgression c. 8000-7500 years BP, the Słupsk Bank was a land area, and the maximum water level of the Baltic Ice Lake and the Ancylus Lake was lower then 24-25 m below the present sea level.

PL

Badania sejsmoakustyczne oraz analizy osadów (litologiczne, palinologiczne, malakologiczne), a zwłaszcza datowania radiowęglowe torfów, pozwoliły na szczegółową charakterystykę stanowiska późnoglacjalnych i wczesnoholoceńskich torfów i osadów jeziornych we wschodniej części Ławicy Słupskiej. Wykazano, że od deglacjacji do początków transgresji litorynowej, około 8000-7500 lat BP, Ławica Słupska była lądem, a maksymalny poziom wód w zbiornikach bałtyckiego jeziora lodowego i jeziora ancylusowego nie był wyższy niż 24-25 m poniżej współczesnego poziomu morza.

9

Rapid sea level changes in the Southern Baltic during late glacial and Early Holocene

Uścinowicz Sz.

Polish Geological Institute Special Papers

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2004

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Vol. 11

9-18

EN

In the area of the southern Baltic Sea, the largest and most violent changes in water level took place in Late Glacial and Early Holocene, during the period between 13.0-8.5 ka BP. These changes depended on the varied glacio-isostatic movements between the northern and southern parts of the Baltic Sea, the glacio-eustatic increase in the ocean level and the closing or opening of the connection between the Baltic Sea basin with the ocean. During the Late Glacial and Early Holocene, the sea level changed within an amplitude as wide as 25-27 m. In some extreme cases, the sea level could have fallen at a rate of about 100-300 mm/a, the sea level rise rate reaching up to about 40-45 mm/a. In Late Glacial and Early Holocene, there were three transgressions: during 12.0-11.2, 11.0-10.3 (the Baltic Ice Lake) and 10.2-9.2 ka BP (the Yoldia Sea and the Ancylus Lake). There were also three regressions, setting on 11.2, 10.3 and 9.2 ka BP. During regressions, depending on the real drainage rate and the local gradient of the bottom inclination, the land possibly grew at a rate of 0.3 to 4 km per year. During transgressions, rate of shoreline migration could reach in some cases up to 150-200 m per year. These processes took place on the surface of the sea bottom currently located at the depth of c. 55 to 25 m below sea level and from 30 to 60 km away from the present-day southern coast of the Baltic Sea. Rapid changes of shoreline position are recorded in progradational barrier structures and in the erosion surfaces of the glacial till and glacio-marine clays.