ARTICLE IN PRESS

Quaternary International 130 (2005) 87–96

*Correspondin

1040-6182/$ - see

doi:10.1016/j.qua

Late Glacial and Holocene depositional history in the eastern part ofthe Szczecin Lagoon (Great Lagoon) basin—NW Poland

Ryszard K. Bor !owka*, Andrzej Osadczuk, Andrzej Witkowski,Brygida Wawrzyniak-Wydrowska, Tomasz Duda

University of Szczecin, Institute of Marine Sciences, W)aska 13, Pl–71-415 Szczecin, Poland

Available online 2 July 2004

Abstract

Analyses on 27 sediment cores taken from the bottom of the Szczecin Lagoon allowed environmental reconstruction of the

postglacial main stages of basin development, based on detailed sedimentological, geochemical, diatomological and malacological

studies of selected key cores. Studies revealed that during the Late Glacial and Holocene this area developed in several stages. In the

Late Glacial the whole study area constituted a low alluvial plain. At the turn from Younger Dryas to Holocene the alluvial plain

was cut through by the Odra river to a level of 10–11m below sea level (b.s.l.). Along with the first phases of the Holocene marine

transgression at the southern Baltic Sea’s coasts the accumulation of the limnic-swampy deposits began in this lower part of the

Odra valley. At ca. 6–6.5 ka BP the transgression proceeded and Littorina Sea waters flooded the area. At that time the Szczecin

Lagoon constituted a marine embayment in which series of sands, partly rich in malacofauna, was deposited. The development of

the Swina barrier resulted in the isolation of the embayment from the direct inflow of Baltic Sea waters.

r 2004 Elsevier Ltd and INQUA. All rights reserved.

1. Introduction

The Holocene development of the southern Baltic Seashows distinct differences in comparison to the otherareas of the Baltic, e.g. isostatic rebound processes at theScandinavian coasts, which are absent in the SouthernBaltic Sea (e.g. Svensson, 1991; Bj .orck, 1995). Thus thesouthern coasts of the Baltic Sea usually show sedimen-tary sequences reflecting marine transgressions. Begin-ning from the onset of the Boreal and AtlanticChronozones the global eustatic sea level rise causedan inflow of marine waters. This resulted in changes ofthe water chemistry and in a general water level rise. Therising water level led to flooding of the former terrestrial(lacustrine) environment and the shores were translo-cated towards south, beginning from ca. 7000BP. Thissequence of events is typical for the Pomeranian Bayand the neighbouring basins of the lower Odra Valleyand the Szczecin Lagoon (Kolp, 1990; Kliewe andJanke, 1991; Kramarska, 1999; Broszinski, 2002).The Szczecin Lagoon (Fig. 1) together with the Great

D)abie and Small D)abie lakes to the south constitutes a

g author.

front matter r 2004 Elsevier Ltd and INQUA. All rights

int.2004.04.034

system of extensive sedimentary basins in whichsedimentation of allochthonous and autochthonousdeposits took place during most of the last millenia.These deposits result from terrigenous fluviallytransported material and in situ produced biogenousand chemogenous sediments. The major source ofthe terrigenous material was the Odra River. However,during storm-induced high levels of the PomeranianBay also the Swina, Dziwna and Peene Riverstransported sediments into the lagoon. The SzczecinLagoon area is primarily the valley floor of the deglacialOdra River valley which, due to the post-glacialtransgression, was transformed into a lagoon when thespits along the present coast of the Baltic Sea wereformed.Earlier geological studies of the Szczecin Lagoon

(e.g. Wypych, 1980; Leipe et al., 1998; Bor !owka et al.,1999a–c; M .uller, 2001) were principally based onanalyses of solitary and often randomly located cores.The present paper is based on the results of acomprehensive geophysical survey and coring pro-gramme of the Lagoon, aiming towards the recognitionof depositional sequences with a time span from late-glacial to the present.

reserved.

ARTICLE IN PRESS

Fig. 2. Enlarged section of the seismoacoustic profile from the NE

part of the study area (for location see Fig. 1).

Fig. 1. Location of the study area. Indicated are positions of the

seismoacoustic profiles and of vibrocores.

R.K. Bor !owka et al. / Quaternary International 130 (2005) 87–9688

2. Materials and methods

Seismoacoustic studies of the Szczecin Lagoon sedi-ments were done by means of the sub-bottom profiler‘‘Seabed Oretech 3010-S’’ at 5 kHz. Altogether 18seismo-acoustic profiles, 200 km in total length, wereaccomplished (Figs. 1 and 2). Based on these results 27sites were chosen for vibrocoring (Fig. 1). Vibrocoreswere taken by means of a VKG-3 device, 4m long and9.1 cm of internal diameter. The cores 3–4m in lengthwere cut into 1m intervals and stored at a temperatureof 3–4�C. In laboratory conditions all cores weredocumented photographically and their lithology wasdescribed macroscopically. Included in the descriptionwere the colour of the sediments, structural and texturalfeatures, organic matter content and the presenceof fossil macro-remnants. Sub-sampling was donefor granulometric, diatomological, palynological,

malacological and geochemical analyses and for 14Cdating. Detailed information on 14C dating is providedin Table 1.

3. The study area

The investigations were carried out in the easternpart, deep-water part of the Szczecin Lagoon. TheSzczecin Lagoon is a shallow water body with a surfacearea of 687 km2. The recent depth of the lagoon does notexceed 8.5m and has an average of c. 3.5m. Almost half(48.3%) of the lagoonary surface area has water depthsranging from 4 to 6m.The northern boundary of the lagoon, which also

separates it from the Baltic Sea, is the Swina Bar. Thisbar complex is made up of Holocene beach deposits anddeltaic deposits of the Swina River. In the south thelagoon is gradually getting narrower (Fig. 1) forming theso-called Roztoka Odrza !nska (Odra mouth) and finallythe Lower Odra Valley.

4. Results

The total number of studied cores amounted to 27.Results of these studies show that the sedimentary infillof the Szczecin Lagoon is composed of several deposi-tional units, indicating different and changing deposi-tional environment. The following depositional seriescan be distinguished in stratigraphic order: fluvial,limnic-swampy, marine and lagoonal. The best examplesof this development and succession were observed incores 35/99, 42/99 and 3/96 (Figs. 3 and 4).

ARTIC

LEIN

PRES

S

Table 1

Radiocarbon dates of limnic and swampy deposits from the Szczecin Lagoon

Sample name Core no. Depth below bed

surface (m)

Depth below sea

level (m)

Material Radiocarbon age

(14C yr B.P.)

Calibrated age

(cal yr B.P.)

Calibrated age

range (1 sigma)

(cal yr B.P.)

Laboratory

number

Zalew Szczeci !nski (2/98/0.64–0.75) 2/98 0.64–0.75 6.64–6.75 Peat 74107140 82357125 8360–8110 Gd-15096

Zalew Szczeci !nski (2/98/0.75–0.81) 2/98 0.75–0.81 6.75–6.81 Peat 74307140 82657115 8380–8150 Gd-12233

Zalew Szczeci !nski (9/96/97–100) 9/96 4.90–5.00 9.90–10.00 Organic mud 72507130 80607130 8190–7930 Gd-15092

Zalew Szczeci !nski 26/56 26/99 2.75–2.80 8.70–8.75 Detritus gyttja 72407120 80607120 8180–7940 Gd-15103

Zalew Szczeci !nski 26/65 26/99 3.20–3.25 9.15–9.20 Mudy gyttja 79907110 88507160 9010–8690 Gd-12236

Zalew Szczeci !nski 26/69 26/99 3.40–3.45 9.35–9.40 Organic mud 73307110 80907120 8210–7970 Gd-15101

Zalew Szczeci !nski 28/57 28/99 2.80–2.85 8.52–8.57 Organic mud 62307250 71257325 7450–6800 Gd-16027

Zalew Szczeci !nski 28/59–60 28/99 2.90–3.00 8.62–8.72 Detritus gyttja 77007120 84907120 8610–8370 Gd-12234

Zalew Szczeci !nski 29/26 29/99 1.24–1.30 6.96–7.02 Organic mud 7050790 78557105 7960–7750 Gd-12241

Zalew Szczeci !nski 29/31 29/99 1.49–1.53 7.21–7.25 Detritus gyttja 69307110 77607100 7860–7660 Gd-12244

Zalew Szczeci !nski 35/41–42 35/99 1.92–2.00 6.93–7.01 Peat 7030790 78507100 7950–7750 Gd-12223

Zalew Szczeci !nski 35/46 35/99 2.15–2.20 7.16–7.21 Peat 88107110 98757275 10150– 9600 Gd-12224

Zalew Szczeci !nski 35/50 35/99 2.35–2.40 7.36–7.41 Detritus gyttja 104207180 123007350 12650–11950 Gd-15090

Zalew Szczeci !nski 36/23–24 36/99 1.10–1.20 7.05–7.15 Peat 78707100 86657125 8790–8540 Gd-12242

Zalew Szczeci !nski 36/27 36/99 1.30–1.33 7.25–7.28 Peat 71707110 79507110 8060–7840 Gd-12243

Zalew Szczeci !nski 36/48 36/99 2.82–2.86 8.77–8.81 Organic mud 111007130 130557145 13200–12910 Gd-12245

Zalew Szczeci !nski 37/53 37/99 2.62–2.66 8.48–8.52 Organic mud 119007230 138757425 14300–13450 Gd-15086

Zalew Szczeci !nski 39/61–62 39/99 3.00–3.10 8.77–8.87 Detritus gyttja 81807160 91007350 9450–8750 Gd-15078

Zalew Szczeci !nski 42/30 42/99 1.50–1.55 7.55–7.60 Detritus gyttja 6850790 7685775 7760–7610 Gd-12217

Zalew Szczeci !nski 42/36 42/99 1.80–1.86 7.85–7.91 Detritus gyttja 7230780 8100790 8190–8010 Gd-12222

Zalew Szczeci !nski 42/41 42/99 2.00–2.03 8.05–8.08 Peat 100307120 115007250 11750–11250 Gd-12214

Zalew Szczeci !nski 42/44 42/99 2.10–2.14 8.15–8.19 Peat 114507140 133507200 13550–13150 Gd-12220

Zalew Szczeci !nski 42/45 42/99 2.14–2.18 8.19–8.23 Muddy peat 101807380 119507700 12650–11250 Gd-16029

Zalew Szczeci !nski 43/10 43/99 0.44–0.50 5.76–5.82 Detritus gyttja 70807100 78807100 7980–7780 Gd-12235

Zalew Szczeci !nski 43/12–13 43/99 0.55–0.63 5.87–5.95 Detritus gyttja 77707130 85557165 8720–8390 Gd-15104

Zalew Szczeci !nski 43/32–33 43/99 1.51–1.61 6.83–6.93 Organic mud 99807110 114357205 11640–11230 Gd-12238

Zalew Szczeci !nski 47/34–35 47/99 1.66–1.75 7.58–7.67 Detritus gyttja 7260775 80707100 8170–7970 Gd-12225

Zalew Szczeci !nski 47/48–49 47/99 2.35–2.45 8.27–8.37 Muddy gyttja 78507100 87257275 9000–8450 Gd-12226

R.K

.B

or!ow

ka

eta

l./

Qu

atern

ary

Intern

atio

na

l1

30

(2

00

5)

87

–9

689

ARTICLE IN PRESS

Fig. 4. Core log 3/96 including results of the malacological analysis (for explanations see Fig. 3).

Fig. 3. Core logs 35/99 and 42/99: 1—shell layer; 2—algal gyttja with shells; 3—algal gyttja; 4—mineral gyttja; 5—silty gyttja; 6—sandy gyttja; 7—

detritus gyttja; 8—peat; 9—sand; 10—silty sand.

R.K. Bor !owka et al. / Quaternary International 130 (2005) 87–9690

4.1. Late Glacial sediments

4.1.1. Unit A: fluvial environment

The basement of the organic deposits filling in theSzczecin Lagoon basin is of fluvial origin. The coringequipment could not penetrate the full thickness of thisunit but a data from older studies (e.g. Wypych, 1980)indicate that it reaches at least the depth of 24m b.s.l.The total thickness could thus reach 14–16m, possibly

with the lower part representing fluvio-glacial deposits.The maximum penetration at coring these sedimentswas 3.5m. The sediments are well- to very well-sortedfine to medium sands, in the lower parts sometimesshowing cross bedding. In the uppermost part the sandis more fine-grained and the beds show a horizontallamination.Within some of the cores (e.g. 35/99; 42/99 and 47/

99), the upper part of the unit A sands display numerous

ARTICLE IN PRESSR.K. Bor !owka et al. / Quaternary International 130 (2005) 87–96 91

root horizons and charcoal intraclasts. In core (36/99,37/99 and 42/99) the unit A fluvial sand is interbeddedwith a thin subunit (10–20 cm) of organic-rich, clayey-muddy sediments, interpreted to be of limnic-swampyorigin. 14C dates (core 42/99) of this layer indicate that itis of Aller .od age.The morphology of the upper surface of the unit A

fluvial sediments is variable (Fig. 5A). Its deepestposition was recorded in the middle part of the GreatLagoon, where it appears at 10–11m b.s.l. and in thenorth-western part, close to the border of the LittleLagoon. In the eastern and western part of the coast ofthe Great Lagoon the level of the upper boundary risesto 6–7m b.s.l. The analysis of the seismo-acoustic datathus reveals the presence of an elongated basin with arelative height of up to c. 3m within the upper surface ofthe fluvial sediments, which is interpreted as anerosional channel related to the lateral migration ofthe Pre-Odra River.

Fig. 5. Szczecin Lagoon. Morphology of the top surface of the fluvial (Unit

series (Unit D).

4.2. Holocene sediments

4.2.1. Unit B: Limnic-swampy environment

Organic deposits, though absent in some cores, drapethe unit A top surface with a sediment thickness between10 cm and 2m. Spatial analysis of its thickness distribu-tion shows that these sediments primarily fill theelongated depressions within the upper boundary ofthe fluvial unit A sediments, particularly in the middlepart of the Great Lagoon (Fig. 5B). They are interpretedas ancient river beds of the Pre-Odra River.The unit B sediments are predominantly composed of

gyttja, sometimes underlain or overlain by well decom-posed peat with wood pieces. The organic mattercontent of the gyttja range from 20% to 80%, some-times with a distinct portion of CaCO3. The gyttjadisplay a freshwater molluscan fauna with the dominanttaxa being characteristic for small lacustrine basins, e.g.Bithynia tentaculata, Valvata piscinalis, Lymnaea sp. and

A), swampy-limnic (Unit B), brackish-marine (Unit C) and lagoonary

ARTICLE IN PRESSR.K. Bor !owka et al. / Quaternary International 130 (2005) 87–9692

Pisidium sp. Some fish remnants were also sporadicallyidentified within the sediment. An abundant diatomflora was recorded (Fig. 6) predominated by theepiphytic taxa representing genera of Cocconeis, Epithe-

mia, Fragilaria and Gomphonema. Their predominationindicate the existence of shallow freshwater bodies withabundant macro-plants. Furthermore, the dominance ofbenthic taxa also indicates a shallow water environmentwith good light conditions. The frequency (up to 6%) ofbrackish-water taxa increases in the upper part of theunit, e.g. represented by Fragilaria schulzii, Navicula

salinarum and Melosira nummuloides.In more shallow parts of the basin, unit B is

represented only by peat layers up to ca. 2m inthickness. Peat type varies, with carex and carex-reedypeat in the basal part of the profile and woody andwoody-carex peat in the upper part. Based on sedimenttypes and macro-fossil content, unit B is interpreted asdeposited in a varying swampy to limnic environment.The deposition started as indicated from 14C dating(Fig. 3), in the beginning of the Holocene and lasted upto ca. 6200 BP (Bor !owka et al., 2001). Existing dataindicate their formation to start after a distinctenvironmental shift from fluvial conditions to shallowlimnic conditions. Only one core (43/99, Fig. 1) recordsfluvial sediment interbedding (c. 1m sands) within theunit B limnic sediments.

4.2.2. Unit C: marine environment

The base of the unit C sediments is marked by adistinct erosional discontinuity and occurs in almost allcores taken from the deeper part of the Great Lagoon.They are characterised by increased contents of thecoarse fraction and relatively good sorting. The thick-ness of the marine unit C sediment is variable, but itrarely exceeds 1.5m. Its greatest thickness was recordedin the northern part of the Great Lagoon (Fig. 5C); incore 31/99 (Fig. 1) it attained ca. 3m without being

Fig. 6. Distribution of diatom ecological groups in core No. 3

totally penetrated. The marine sediments were notencountered in the lateral, more highly siltated partsof the basin.With respect to lithology, the marine sediments are

composed of sands and muddy sands. They differ fromthe unit A fluvial sands with respect to organic matter,Na, K, Ca, Mg and Fe contents (Fig. 6), finer grain-sizeand less sorting.The results from the malacological analyses are highly

indicative of a marine environment. The mollusc faunaof the sandy sediments is dominated by Cardium

glaucum, forming well developed populations with shellsizes larger than in the recent Pomeranian Bay.Accompanying species are Hydrobia ventrosa, H. ulvae

and H. balthica (Fig. 4).A characteristic feature of the marine sediments is

either a complete absence or a scarce, usually highlyfragmented diatom flora (Fig. 7). This might be relatedto a high sedimentation rate of the sandy sediments andto current and wave action. The taxa found, e.g.Catenula adhaerens and Fragilaria fasciculata, aretypical for a shallow marine littoral environment.

4.2.3. Unit D: Lagoon environment

This unit differs from the marine unit with respect to ahigher content of organic matter, to their chemicalcomposition and the species composition of the mollus-can fauna. Locally, its thickness exceeds 2m in themiddle part of the Great Lagoon, but it is very thin inthe western part (Fig. 5D).The subfossil malacofauna of the lagoonary sedi-

ments is predominantly composed of freshwater taxaincluding Bithynia tentaculata, Valvata piscinalis, Vivi-

parus sp., Pisidium sp., Unio sp., and Dreissena

polymorpha. Presently, the latter species forms extensivecolonies on some localities of the Great Lagoon bottom(e.g. core 35/99). The diatom flora (Fig. 7) is dominatedby freshwater planktonic taxa such as Aulacoseira

/96. Solid area stands for %, dotted area stands for %.

ARTICLE IN PRESS

Fig. 7. Distribution of geochemical elements in core No. 3/96.

R.K. Bor !owka et al. / Quaternary International 130 (2005) 87–96 93

granulata, A. islandica and A. muzzanensis. Within theyoungest deposits halophilous and brackish-water taxaappear, attaining percentages up to 9.6% and repre-sented by taxa such as Diploneis smithii, Fragilaria

sopotensis and Opephora olsenii.The lagoonary sediments show a distinct bipartition

with respect to geochemical analyses (Fig. 6). Its upperpart, up to half a meter in thickness, is characterised bymarkedly increased concentrations of heavy metals (Zn,Pb, Cu) and Mn. In comparison to the lower part thereis a nine-fold increase in Zn and an almost five-foldincrease in Cu content.

5. Discussion

The analysis of the stratigraphic and spatial varia-bility of the Great Lagoon sedimentary infill enables thedistinction of several development stages of this deposi-tional basin. Their chronostratigraphic position is basedon numerous radiocarbon dates of the limnic-swampydeposits (Bor !owka et al., 2001). A summary of thepaleogeographic development is presented in Fig. 8.The Pre-Aller .od stage is represented by fluvial

sediments (unit A). Their origin is related to thedevelopment of the lower Odra River valley from theend of the last glaciation to the distinct climateamelioration during the Aller .od. Within this period, aseries of six terrace levels in the area of the recent OdraRiver valley and the Szczecin Lagoon was formed. Thehighest is raised up to ca. 20m a.s.l., whereas the lowestone is found at ca. 10m b.s.l. (Karczewski, 1968; Duda,1999). The age of particular terraces is not known yet.However, within terrace sediments at an altitude of ca.

8m b.s.l., there are thin intercalations of limnic-swampydeposits, dated to the Aller .od.It is hard to reconstruct the late glacial bottom of the

Odra River Valley and the course of the river bed itself.Paleohydrological studies (Kozarski and Rotnicki, 1977;Kozarski, 1983; Rotnicki, 1983, 1991) carried out for theOdra River catchment area and some of its tributariesrevealed, that during the Late Glacial, large meanderingriver beds were formed within the bottom of some of thecontemporary valleys. Compared to the Early andMiddle Holocene they discharged several times highermagnitudes of water (Rotnicki, 1983, 1991). However, itcannot be excluded that the lower Odra was a braidedriver, similar to other rivers draining the northern slopeof Pomerania (Florek, 1996). This problem thus remainsan open question.From the Aller .od stage, it is known that some parts of

the Szczecin Lagoon were covered by shallow waterbodies and peat bogs (Fig. 8), giving rise to sedimentsinterfingering with the predominantly fluvial A sedi-ments. Simultaneously the surroundings of the SzczecinLagoon were characterised by rather dense pine-birchforests and by patches of heliophilous plants. This isdemonstrated not only from the results of paleobotani-cal analyses (Lata"owa, 1989, Lata"owa, 1999a, b), butalso indicated by well developed and widely distributedcovers of fossil soils on Wolin Island (Bor !owka et al.,1982, 1986, 1999a, b).The Younger Dryas stage is marked by a distinct

acceleration of fluvial processes, and particularly by anaggradation of sandy deposits at earlier developedcovers of Aller .od limnic-swampy deposits in the GreatLagoon area. In cores 36/99 and 37/99, post-Aller .odfluvial deposits attain a thickness exceeding 1.5m. This

ARTICLE IN PRESS

Fig. 8. Szczecin Lagoon. Litho- and chronostratigraphy of the infilling

deposits.

R.K. Bor !owka et al. / Quaternary International 130 (2005) 87–9694

was probably related to the deterioration of climaticconditions during Younger Dryas, causing the disap-pearance of forest stands and acceleration of soil erosionprocesses (Lata"owa, 1999a, b). There are also indica-tions on the intensification of periglacial and aeolianprocesses (Bor !owka et al., 1999a, b). During that periodthere was probably a distinct increase in the sedimentload, transported by the Odra River.The Early and Middle Holocene stages encompass the

time span from the beginning of the Preboreal to thesecond half of the Atlantic period (B10,250–6200 yr BP)at which the Great Lagoon area was predominantlyfilled in with limnic-swampy deposits (unit B; Fig. 8). Itis highly likely that during that time the Pre-Odra wasan anastomosing river, flowing through swamps andreedy areas, similar to the recent lower Odra.

The Late-Atlantic stage is marked by a phase ofmarine transgression (the Littorina transgression) in theGreat Lagoon area. Almost the whole lagoon consti-tuted an open marine bay at that time. It extendedsouthward into the lower Odra River valley up to aplace where the recent town Szczecin is located (Bor-!owka and Duda, 2002) and penetrated the mouths ofsmaller rivers discharging into the Szczecin Lagoon, e.g.Uecker valley in the area of Ueckerm .unde (Bramer,1978). The water salinity was higher than in the presentPomeranian Bay, as indicated by preserved shells ofCardium glaucum, reaching sizes characteristic for watersalinity values higher than 6–7% (Bor !owka et al., 2000).The duration and rate of this transgression in the area

of the Pomeranian Bay and Szczecin Lagoon is notsatisfactorily known. It cannot be excluded that it was adisastrous event, as suggested by Rosa (1963). It ispossible that, during extremely strong storms, a sandbar between the Odra Bank and eastward up to theregion of Ko"obrzeg was disrupted and destroyed(Mojski, 1995; Kramarska, 1999). Radiocarbon datesof limnic-swampy deposits from the Pomeranian Bay(Kramarska, 1999) and from the Szczecin Lagoon(Wypych, 1980; Bor !owka et al., 2001), showing verysimilar ages of these deposits in both areas, indicate arelatively fast rate of this transgression.The Late-Holocene stage, encompassing the Subbor-

eal and the Subatlantic periods began with the isolationof the Szczecin Lagoon from direct marine influences.Intensified abrasion processes at morainic cliffs ofUsedom and Wolin Islands resulted in a rapid growthof bars and the development of a sand barrier in the areaof the recent Swina Gate (Keilhack, 1912; Prusinkiewiczand Nory!skiewicz, 1966). Simultaneously the formationof the Swina back-delta started behind the barrier. Itssubmerged part, the so-called Wyskok Krzecki, extendsfar into the lagoon’s interior and is dipping with arelatively steep slope to the depth of 6.5–7m.The isolation of the Great Lagoon from direct marine

influences resulted in a change of the depositionalprocesses. This is indicated in the deposited sediments(unit D, Fig. 8) by an increase of the organic mattercontent and the replacement of marine molluscs byfreshwater taxa (Bor !owka et al., 2000). Lagoonarysediments deposited during that time also contain apredominantly freshwater diatom flora (Bor !owka et al.,1999). The accumulation of this type of deposits hascontinued in the Great Lagoon until present times. Thesedimentation rate is highly variable and ranges from ca.20 cm per century in the Little Lagoon (Leipe et al.,1995) to ca. 50 cm in the eastern part of the GreatLagoon (Bor !owka, 2001). No deposition or very lowdeposition rates are characteristic for regions neighbour-ing the western coast of the Great lagoon, which arelocated on a distinct plateau on top of the fluvial unit Asediments.

ARTICLE IN PRESSR.K. Bor !owka et al. / Quaternary International 130 (2005) 87–96 95

6. Concluding remarks

The present geological studies have shown that thesediments filling the deep-water part of the SzczecinLagoon are deposited on two morphological levels.Older sediments, which encompass (e.g.) Aller .od lacus-trine series are located on the higher level, c. 7–8m b.s.l.Limnic and swampy sediments were initially depositedonly at the lower terrace within the period of 10 to6–6.5 ka BP. Later on, at ca. 8 ka BP, the swampysedimentation inundated also the higher level. Beginningfrom this time the whole Great Lagoon constituted avast and flat swampy plain, cut by the anostomosingOdra River.At c. 6–6.6 ka BP the whole low lying area was

affected by a marine transgression and for a short periodan open marine embayment existed, characterised bysalinity values higher than the recent Pomeranian Bay.However, this embayment was rapidly isolated from thedirect inflows of the Baltic Sea due to build-up of theUsedom and Wollin spits. The youngest sediments arelagoonary deposits, characterised by a most variablethickness: thin on the older terrace level, which occurs athigher altitude, while thick above the marine sands.

Acknowledgements

The authors wish to express their gratitude to theteam of Operational Oceanography from the MaritimeInstitute in Gda !nsk for accomplishing geophysicalsurvey and coring works in 1998 and 1999. We alsothank our students from the Institute of MarineSciences, Faculty of Natural Sciences of the Universityof Szczecin. This in particular is directed to KrzysztofGusar, Dariusz Sikorski, Dariusz Wereszka and RobertWozi !nski for their help in coring works in the GreatLagoon and Dgabie Lake during winter 1995/96 and 96/97. The authors are grateful to Dr. Wolfram Lemkefrom the Baltic Sea Research Institute in Warnem .undefor critical reading of the manuscript. The study wasfinanced by Committee on Scientific Research (KBN),Warsaw, Poland within the framework of project6PO4E 00 216.

References

Bj .orck, S., 1995. A review of the history of the Baltic Sea, 13.0–8.0 ka

BP. Quaternary International 27 (1), 19–40.

Bor !owka, R.K., 2001. Stratigraphical variability of the chemical

composition of deposits infilling the Szczecin Lagoon and D)abie

Lake. In: Florek, W. (Ed.), Geology and Geomorphology of the

Baltic Sea Southern Coast, Vol. 4. Pomorska Akademia Pedago-

giczna, S"upsk, pp. 9–24 (in Polish).

Bor !owka, R.K., Duda, T., 2002. A locality of the Holocene marine

deposits in the Lower Odra Valley in Szczecin, in press.

Bor !owka, R.K., Gonera, P., Kostrzewski, A., Zwoli !nski, Z., 1982.

Origin, age and palaeogeographical significance of cover sands in

the Wolin end moraine area, North West Poland. Quaestiones

Geographicae 8, 19–36.

Bor !owka, R.K., Gonera, P., Kostrzewski, A., Nowaczyk, B., Zwoli-!nski, Z., 1986. Stratigraphy of eolian deposits in Wolin Island and

the surrounding area, North-West Poland. Boreas 15, 301–309.

Bor !owka, R.K., Belczy !nska, A., Duda, T., Babski, K., 1999a.

Postglacial development of the Wollin end moraine in the light of

lithostratigraphic analysis of cover deposits. In: Bor !owka, R.K.

(Ed.), Geology, Hydrogeology and Environmental Protection of

the Western Pomerania coast. LXX Meeting of the Polish

Geological Society. Szczecin, pp. 133–140 (in Polish).

Bor !owka, R.K., Belczy !nska, A., Tomkowiak, J., 1999b. Morphologi-

cal features and some chemical properties of fossil soils developed

within the aeolian sands in the vicinity of !Swi)etouj!scie and Grodno.

In: Bor !owka, R.K., M"ynarczyk, Z., Wojciechowski, A. (Eds.),

Evolution of the Southern Baltic Sea Coastal Geosystems. Bogucki

Wydawnictwo Naukowe, Pozna !n-Szczecin, pp. 37–42 (in Polish).

Bor !owka, R.K., Witkowski, A., Tomkowiak, J., Olas, M., Gusar, K.,

Liszkiewicz, E., 1999c. Stratigraphic and spatial lithological and

geochemical variability of sediments in the Szczecin Haff and

adjacent basins. In: Bor !owka, R.K., M"ynarczyk, Z., Wojcie-

chowski, A. (Eds.), Evolution of the Southern Baltic Sea Coastal

Geosystems. Bogucki Wydawnictwo Naukowe, Pozna !n-Szczecin,

pp. 55–62 (in Polish).

Bor !owka, R.K., Wawrzyniak-Wydrowska, B., Witkowski, A., Wozi !n-

ski, R., 2000. Holocene molluscs assemblages in the deposits of the

Gulf of Szczecin. Folia Malacologica 8 (4), 287.

Bor !owka, R.K., Osadczuk, A., Duda, T., Pazdur, A., Pawlyta, J.,

2001. Lithostratigraphy and chronostratigraphy of the infilling

deposits the Szczecin Lagoon, Northwestern Poland. Seventh

International Conference ‘‘Methods of Absolute Chronology’’

23–26th April 2001, Ustro !n, Poland. pp. 71–72 (Book of

Abstracts).

Bramer, H., 1978. .Uber Transgressionsvorg.ange am S .udrand des

Kleinen Haffs. Wissenschaftliche Zeitschrift der E.-M. Arndt-

Universit.at Greifswald, Jahrgang 27, Mathematisch-naturwis-

senschaftliche Reihe Heft 1/2, pp. 11–15.

Broszinski, A., 2002. Die subfossile Diatomeenflora der westlichen

Ostsee. Biostratigraphische Untersuchungen an sp.at- und post-

glazialen Sedimenten des Kattegats, der Kieler Bucht und der

Pommerschen Bucht. Ph.D. Thesis, J.-W. Goethe University

Frankfurt am Main.

Duda, T., 1999. Phytogenic deposits in the Lower Odra Valley: their

thickness, formation, lithology and age. In: Bor !owka, R.K.,

M"ynarczyk, Z., Wojciechowski, A. (Eds.), Evolution of the

Southern Baltic Sea Coastal Geosystems. Bogucki Wydawnictwo

Naukowe, Pozna !n-Szczecin, 73–78 (in Polish).

Florek, W., 1996. Late Vistulian and Holocene development of the

North Pomeranian river valleys and the influence of South Baltic

neotectonics. Zeitschrift f .ur Geomorphologie 102 (Suppl.- Bd.),

169–183.

Karczewski, A., 1968. Inflow of the Odra lobe recession on origin and

development of valley system of the My!sliborskie Lakeland and

Szczecin Lowland. Pozna !nskie Towarzystwo Przyjaci !o" Nauk,

Prace Komisji Geograficzno-Geologicznej 8, 1–106.

Keilhack, K., 1912. Die Verlandung der Swinepforte. Jahrbuch

der K .oniglich Preussischen Geologischen Landesanstalt 32 (2),

209–244.

Kliewe, H., Janke, W., 1991. Holoz.aner K .ustenausgleich im s .udlichen

Ostseegebiet bei besonderer Ber .ucksichtigung der

Boddenausgleichsk .uste Vorpommerns. Pettermans Geographische

Mitteilungen 135 (1), 1–14.

Kolp, O., 1990. The Ancylus Lake phase of the Post-Glacial evolution

of the Baltic Sea. Quaestiones Geographiceae 13/14, 69–86.

ARTICLE IN PRESSR.K. Bor !owka et al. / Quaternary International 130 (2005) 87–9696

Kozarski, S., 1983. River channel adjustment to climatic change

in west central Poland. In: Gregory, K.J. (Ed.), Background

to Palaeohydrology: a perspective. Wiley, Chichester,

pp. 355–374.

Kozarski, S., Rotnicki, K., 1977. Valley floors and changes of river

channel patterns in the North Polish Plain during the Late W .urm

and Holocene. Quaestiones Geographiceae 4, 51–93.

Kramarska, R., 1999. Quaternary Geology of the south-western Baltic

Sea. In: Bor !owka, R.K. (Ed.), Geology, Hydrogeology and

Environmental Protection of the Western Pomerania coast. LXX

Meeting of the Polish Geological Society. Szczecin, pp. 43–52

(in Polish).

Lata"owa, M., 1999a. Hydrological changes caused by the climatic

factor and human activity and their record in the Ko"czewopeatbog and lacustrine deposits of the Racze Lake. In: Bor !owka,

R.K., M"ynarczyk, Z., Wojciechowski, A. (Eds.), Evolution of the

Southern Baltic Sea Coastal Geosystems. Bogucki Wydawnictwo

Naukowe. Pozna !n-Szczecin, pp. 99–103 (in Polish, English

summary).

Lata"owa, M., 1999b. Late Vistulian vegetation on Wolin Island

(NW Poland)—the preliminary results. In: Bor !owka, R.K.

(Ed.), Quaternary Studies in Poland, Special Issue,

pp. 147–156.

Leipe, T., Neumann, T., Emeis, K.-Ch., 1995. Schwermetallverteilung

in holoz.anen Ostseesedimenten. Geowissenschaften 13 (12),

470–478.

Leipe, T., Eidam, J., Lampe, R., Meyer, H., Neumann, T., Osadczuk,

A., Janke, W., Puff, T., Blanz, T., Gingele, T.X., Dannenberger,

D., Witt, G., 1998. Das Oderhaff. Beitr.age zur Rekonstruktion der

holoz.anen geologischen Entwicklung und anthropogenen Beein-

flussung des Oder- .Astuars. Institut f .ur Ostseeforschung Warnem-

.unde. Meereswissenschaftliche Berichte 28, 1–61.

Mojski, J.E. (Ed.), 1995. Geological Atlas of the Southern Baltic.

Polish Geological Institute. Sopot-Warszawa.

M .uller, A., 2001. Late- and Postglacial Sea-Level Change and

Paleoenvironments in the Oder Estuary, Southern Baltic Sea.

Quaternary Research 55 (1), 86–96.

Prusinkiewicz, Z., Nory!skiewicz, B., 1966. Problem of age of podsols

on brown dunes of Bay Bars of River !Swina in the light of a

palynological analysis and dating by radiocargon 14C. Zeszyty

Naukowe Uniwersytetu Miko"aja Kopernika w Toruniu Geografia

5, 75–88 (in Polish).

Rosa, B., 1963. .Uber die morphologische Entwicklung der K .uste Polen

im Lichte der alten Strandformen. Studia Societatis Scientiarum

Torunensis 5, 1–172.

Rotnicki, K., 1983. Modelling past discharges of meandering rivers in

the North Polish Plain in the Late Glacial and Holocene. In:

Gregory, K.J. (Ed.), Background to Palaeohydrology: A Perspec-

tive. Wiley, Chichester, pp. 321–354.

Rotnicki, K., 1991. Retrodiction of palaeodischarges of meandering

and sinuous alluvial rivers and its Palaeohydroclimatic implica-

tions. In: Starkel, L., Gregory, K.J., Thornes, J.B. (Eds.),

Temperate Palaeohydrology. Wiley, Chichester, pp. 431–471.

Svensson, N.-O., 1991. Late Weichselian and Early Holocene shore

displacement in the Central Baltic Sea. Quaternary International 9,

7–26.

Wypych, K., 1980. Bottom deposits of the Szczecin Lagoon. In:

Majewski, A. (Ed.), Szczecin Lagoon. Instytut Meteorologii i

Gospodarki Wodnej. Wydawnictwa Komunikacji i Ł)aczno!sci.

Warszawa, pp. 54–72 (in Polish).