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1

Origin and significance of early-diagenetic calcite concretions and barite from Silurian black shales in the East European Craton, Poland

Bojanowski Maciej J., Kędzior Artur, Porębski Szczepan J., Radzikowska Magdalena

Acta Geologica Polonica

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2019

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Vol. 69, no. 3

403--430

EN

The Silurian Pelplin Formation is a part of a thick, mud-prone distal fill of the Caledonian foredeep, which stretches along the western margin of the East European Craton. The Pelplin Formation consists of organic carbon-rich mudstones that have recently been the target of intensive investigations, as they represent a potential source of shale gas. The Pelplin mudstones host numerous calcite concretions containing authigenic pyrite and barite. Mineralogical and petrographic examination (XRD, optical microscopy, cathodoluminoscopy, SEM-EDS) and stable isotope analyses (δ13Corg, δ13C and δ18O of carbonates, δ34S and δ18O of barite) were carried out in order to understand the diagenetic conditions that led to precipitation of this carbonate-sulfide-sulfate paragenesis and to see if the concretions can enhance the understanding of sedimentary settings in the Baltic and Lublin basins during the Silurian. Barite formed during early diagenesis before and during the concretionary growth due to a deceleration of sedimentation during increased primary productivity. The main stages of concretionary growth took place in yet uncompacted sediments shortly after their deposition in the sulfate reduction zone. This precompactional cementation led to preferential preservation of original sedimentary structures, faunal assemblages and earlydiagenetic barite, which have been mostly lost in the surrounding mudstones during burial. These components allowed for the reconstruction of important paleoenvironmental conditions in the Baltic and Lublin basins, such as depth, proximity to the detrital orogenic source and marine primary productivity. Investigation of the concretions also enabled estimation of the magnitude of mechanical compaction of the mudstones and calculation of original sedimentation rates. Moreover, it showed that biogenic methane was produced at an earlydiagenetic stage, whereas thermogenic hydrocarbons migrated through the Pelplin Formation during deep burial.

2

Anthropogenic impact on river basins : temporal evolution of sediment classes and accumulation rates in the northern Tyrrhenian Sea, Italy

Scanu S., de Mendoza F. P., Piazzolla D., Marcelli M.

Oceanological and Hydrobiological Studies

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2015

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Vol. 44, No. 1

74--86

EN

In this study, sedimentological and geochronological data from sections of a core (GRT50) collected in the Northern Latium coastal area were compared to data on pluviometric (rainfall) trends, river flows and the temporal evolution of human interventions in the three most important hydrographic basins (Mignone, Marta and Fiora) of this coastal area. The statistical analysis of pluviometric trends identified variations due to a decreasing trend in the Fiora river basin, whereas in the two other locations the decrease was not so significant. Data from the sedimentological analysis of the core confirmed a progressive decrease in the sandy component, which declined from about 30% to the current level of 7% over the last 36 years. There was no significant variation in the sediment mass accumulation rates (MAR), which were characterized by an almost cyclic trend that was probably determined by the most intense floods in the study area. The results revealed that the variations caused by the fluvial processes have affected the water runoff of the Fiora River, and that the consequent decrease in the sand production has been responsible for the recession of beaches in the coastal area between Tarquinia and Montalto di Castro.

3

Sediment deposition and accumulation rates determined by sediment trap and 210Pb isotope methods in the Outer Puck Bay (Baltic Sea)

Szmytkiewicz A., Zalewska T.

Oceanologia

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2014

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No. 56 (1)

85--106

EN

Two methods - in situ sediment trap experiments and an isotopic method based on measurements of 210Pb activities in the sediment cores taken near the traps - were applied for determining sediment deposition and sediment accumulation rates in the eastern part of Puck Bay. The sediment deposition rate (1.67 mm year-1) based on the in situ measurement was comparable with the sediment accumulation rate calculated using the Constant Flux:Constant Sedimentation Rate model for the isotopic method. The age of the sediment layers was determined with the Constant Rate of Supply model; the deepest layers had accumulated around 1900.

4

Concordant 210 Pb and 137Cs ages of Black Sea anoxic unconsolidated sediments.

Florea N., Cristache C., Oaie G., Duliu O. G.

Geochronometria

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2011

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Vol. 38, no. 2

101-106

EN

Two independent geochronologic radiometric methods: 137 Cs and 210Pb were used to determine the sedimentation rate and subsequently to date the oldest sediments of a 50 cm core containing unconsolidated sediments collected at a depth of 600 m below sea surface in the anoxic zone of the Western Black Sea, off the Romanian town of Constanta. Both methods gave coincident value within experimental uncertainties of 0.42š0.20 mmźy-1 for 137 Cs and 0.49š0.03 mmźy-1 in the case of 210 Pb, within the Constant Initial Concentration model, which gave for the lower most sediments an age of 1.00š0.01 ka. The constant sedimentation model as well as the possible causes of observed discrepancy between experimental uncertainties are discussed.

5

A sedimentation study of St. Ana Lake (Romania) applying the 210 Pb and 137 Cs dating methods.

Begy R. C., Timar-Gabor A., Somlai J., Cosma C.

Geochronometria

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2011

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Vol. 38, no. 2

93-100

EN

The biggest problem with most lakes that have no contact with other water sources and are being charged by precipitation is the massive eutrophication. The aim of this work was to determine the sedimentation rate in order to evaluate the progress of eutrophication for St. Ana Lake (Ciomad Mountain near the Băile Tuşnad in Harghita County (Romania)). The concentration of 210 Pb was determined by means of high resolution gamma spectrometry as well as derived from 210 Po activity which was measured through alpha spectrometry; values obtained are in good agreement. For the excess 210 Pb activity values between 4.0š0.5 Bq/kg and 218š20 Bq/kg have been found. As an alternative method, the 137 Cs dating method was applied as well. Calculated mass sedimentation rates are in the range of 0.06š0.01 to 0.32š0.05 g/cm 2 year with a mean of value of 0.15š0.02 g/cm 2 year. Linear sedimentation rates yielded much higher sedimentation values (between 0.5š0.1 and 7.9š0.7 cm/year with a mean of 2.4š0.6 cm/year), due to the predominant organic matter composition and the long suspension time of the sediment. This is an indication for the process of eutrophication which will probably lead to the transformation of the lake into a peat bog.

6

Comparative investigation of flocculative ability of linear polyacrylamide and polyacrylamide grafted to dextran or dextran sulphate backbone

Konko Y., Kutsevol N., Bezugla T., Syromyatnikov V.

Proceedings of ECOpole

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2008

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Vol. 2, No. 2

337--341

EN

Dextran-graft-polyacrylamide and Dextran Sulphate-graft-polyacrylamide copolymers have been tested as flocculation aids in model kaolin suspensions in comparison with linear Polyacrylamides of the similar molecular weight. According to the sedimentation rate and the final sediment volume the graft copolymers are more effective flocculants than the linear polyacrylamides. According to the supernatant liquid clarity the copolymersare proved to be rather similar to the linear homopolymer. The supernatant clarity is inversely related to the length of the grafts. Due to the most expanded macromolecular conformation in solution the copolymer based on Dextran-Sulphate backbone is the most efficient for water clarification.

PL

Porównano wpływ kopolimeru Dextran-graft-poliakryloamid i siarczanu Dextran-graft-poliakryloamidu oraz liniowego poliakryloamidu o liniowej strukturze i podobnej masie molowej na kłaczkowaniemodelowej zawiesiny kaolinowej. Biorąc pod uwagę szybkość sedymentacji i końcową objętość osadu, kopolimery okazały się być efektywniejszymi flokulantami niż liniowe poliakryloamidy. Klarowność cieczy nad osadem była podobna przy zastosowaniu polimeru i kopolimeru. Zauważono odwrotną zależność pomiędzy odległościamimiędzy wszczepieniami i klarownością cieczy nad osadem. Ze względu na złożoną konformację makromolekuły w roztworze kopolimer z siarczanem Dextran-graft-poliakryloamidu jest najefektywniejszy przy oczyszczaniu wody.

7

Sedimentation rates and dating of bottom sediments in the Southern Baltic Sea region

Suplińska M. M., Pietrzak-Flis Z.

Nukleonika

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2008

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Vol. 53, suppl. 2

105--111

EN

Sedimentation rates and dating of bottom sediments were estimated in two sampling stations of the Gulf of Gdańsk and in four stations in the open sea area. Estimations were based on vertical distributions of 210Pb, 137Cs and 239,240Pu activity concentrations in sediment core samples taken in 1998–2007. Two dating models based on changes of activity concentrations of 210Pbunsup were used: 1) CF:CS (Constant Flux Constant Sedimentation rate-model) and 2) CRS (Constant Rate of Supply-model). 137Cs and 239,240Pu were applied as time markers. 137Cs originates mostly from the Chernobyl accident in 1986, whereas 239,240Pu comes from the global fallout in 1963. The validation of the 210Pb methods was performed by activity peak of 137Cs and 239,240Pu. Sediment accumulation rate (g·cm–2·y–1) was constant along sediment core. Annually accumulated layer, (mm·y–1) decreased with sediment depth in all the locations. In the Gulf of Gdańsk sedimentation rate in the upper layer was about 3.6 mm·y–1, and it decreased in the deeper layers to about 1.1 mm·y–1. Sedimentation rates in the open sea area were lower than in the gulf region and the lowest was observed in the Bornholm Deep, being about 0.95 mm·y–1 in the upper layer and 0.35 mm·y–1 in the deeper layer. The growth of a 5 cm thick layer took 27–37 years in the Gulf of Gdańsk, and 61–105 years in the open sea area. It is suggested that the mean values obtained from the models would give a most reliable estimation of the sedimentation rates.

8

Deposition rate of lake sediments under different alternative stable states

Gąsiorowski M.

Geochronometria

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2008

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Vol. 32

29-35

EN

Sediments of five shallow lakes in Polesie Lubelskie region (Eastern Poland), representing a wide range of nutrient concentration, were dated by Pb-210 method and reliable age-depth models were constructed. These models were a base for studies of relationship between status of lake biocenoses and rate of sedimentation in the lakes. The sedimentation rate does not depend on ecological status of studied lakes. The highest mean sedimentation rate was found in phytoplankton-dominated (Lake Syczyńskie) and phytoplanktonmacrophyte- dominated (Lake Sumin) lakes. Macrophyte-dominated lakes represented intermediate values of deposition rate. Lake depth, area and hydrology are more important factors controlling sedimentation rate. The sedimentation rate was rather stable or changed over the time, depending on human management in the lakes’ drainage basins.

9

Wykorzystanie 210Pb i metali ciężkich do oceny tempa współczesnej sedymentacji zanieczyszczonych osadów fluwialnych w dolinie górnej Warty

Łokas E., Ciszewski D., Wachniew P., Owczarek P.

Przegląd Geologiczny

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2006

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Vol. 54, nr 10

888-894

EN

River floodplains have been recognized as an important sink for suspended sediments and associated contaminants mobilized from upstream catchments. However, information on rates of overbank sedimentation within time span of several tens of years is impossible to obtain using conventional sediment traps. Measurements of the 210Pb content in floodplain sediments provide an alternative approach for obtaining estimates of medium-term (100–150 years) rates of overbank sediment deposition. The use of 210Pb method and heavy metals concentration profiles allowed to obtain retrospective estimates of recent sedimentation rates on floodplain of the Warta River (the Cracow Upland, southern Poland). The results are compared with dating of sediment layers by characteristic peaks of heavy metal concentrations. The highest sediment accretion rate, of the order of 1 cm/year, was found in a levee along river bank. Sediment deposition in flood basin is much slower and usually does not exceed 1 mm/year.

10

Determination of the sediment deposition rates in the Kuwait Bay using 137Cs and 210Pb

Al-Zamel A., Bou-Rabee F., Al-Sarawi M., Olszewski M., Bem H.

Nukleonika

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2006

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Vol. 51,suppl.2

39-44

EN

Five bottom sediment cores from the Kuwait Bay were dated using 210Pb and 137Cs radionuclides. For evaluating the sedimentation rate two methods were applied: geochronology with the constant rate of supply unsupported 210Pb (CRS model) and the Weibull distribution of anthropogenic 137Cs. The sedimentation rates in this region, calculated by the first method ranged from 0.24 to 0.39 cm/year, while the same rates obtained from 137Cs distribution were slightly lower: from 0.1 to 0.25 cm/year. These relatively small differences can be explained by additional input of the Chernobyl accident to the 137Cs inventory in the bottoms sediments of the Northern Hemisphere.

11

Recent sedimentation and eutrophication of kruklin lake after artificial drop in water-level in the middle of 19th century

Gąsiorowski M., Hercman H.

Studia Quaternaria

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2005

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Vol. 22

17-25

EN

Sediments of two short cores collected from two basins of Kruklin Lake were studied by means of 210Pb and Cladocera analyses. The 210Pb allowed to date sediments and was helpful to obtain changes of sedimentation rate during the last two centuries. The CRS model was applied to calculate sediments age. Sedimentation rate differed strongly (from 0.55 cm/yr to 6.25 cm/yr) not only in time, but also between each basin. An accurate chronology of sediments was the basis for tracking of palaeolimnological changes with Cladocera analysis. Cladoceran planktonic:littoral ratio reflects event of artificial drop of lake water-level in the middle of nineteenth century. However, this event was recorded only in sediments of the southern, shallower basin and we suggest, that cladoceran planktonic:littoral ratio is better representative in shallow lakes. Changes of Cladocera assemblage composition suggest also strong eutrophication of lake water during the last century.

12

Recent changes of sedimentation rate in three Vistula oxbow lakes determined by 210Pb dating

Gąsiorowski M., Hercman H.

Geochronometria

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2005

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Vol. 24

33-39

EN

Sediments of three oxbow lakes located in Vistula valley near Warsaw (Poland) were analysed for activity of 210Pb. The sediment age was calculated applying the CRS model. The sedimentation rate was determined for each lake based on the sediment age and thickness under the assumption of constant deposition between dated layers. Sedimentation rate varies in time and between lakes. The major changes of sedimentation rate were correlated with flood events and construction of flood dams that isolate the lakes from the river. The recent differences between the lakes seem to be related to different trophy state and productivity.

13

Isotopic investigations of uppermost sediments from Lake Wigry (NE Poland) and its environment

Pawlyta J., Pazdur A., Piotrowska N., Poręba G., Sikorski J., Szczepanek M., Król K., Rutkowski J., Hałas S.

Geochronometria

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2004

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Vol. 23

71-78

EN

This paper presents the results of the first isotopic investigations of sediments recovered from Lake Wigry (NE-Poland). In the spring/summer 2002 few sediment cores, plant samples and water profiles were collected specially for isotopic investigations. We obtained 210Pb activity profiles, 137Cs activity profiles and 14C activity/age profiles. Apparent ages of carbonate fraction for all sediment cores were determined. Sedimentation rates for collected cores were estimated using 14C dating method. In addition oxygen isotopic ratios of the water profiles, carbon stable isotopes ratio of collected sediment cores were determined.

14

Estimating recent sedimentation rates using 210 PB on the example of morphologically complex lake (Upper Lake Raduńskie, N Poland)

Tylmann W.

Geochronometria

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2004

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Vol. 23

21-26

EN

Upper Lake Raduńskie is a classical channel lake with a typical complexity of lake basin morphology. This study presents the results of 210Pb measurements in four cores of recent sediments taken from different parts of the lake. The unsupported 210Pb activity plotted on a logarithmic scale against the cumulative dry mass decreased almost linearly. Sedimentation rates were determined from the mean slope of the profile (CF:CS model). A diversity of calculated values was significant, the highest value was found in the core RAD02/6 located in the deepest part of the lake. Both 210Pb inventories and fluxes were higher than that expected from atmospheric fallout estimated for this part of Europe. Factors influencing differences between atmospheric fallout and sediment record may include inputs from the catchment and sediment focusing, which seems to be the main reason of sedimentation rates diversity in morphologically complex lakes.

15

Vertical distribution of 137Cs, 210Pb, 226Ra and 239,240Pu in bottom sediments from the Southern Baltic Sea in the years 1998-2000

Suplińska M.

Nukleonika

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2002

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Vol. 47, nr 2

45-52

EN

This paper presents vertical distribution of 137Cs, 226Ra and 239,240Pu in bottom sediments collected from the Southern Baltic Sea in the years 1998-2000. In the southern part of Baltic Sea the highest concentrations of 137Cs and 239,240Pu were observed at the Gulf of Gdansk. Deposition of 137Cs ranged from 1990š402 Bq m-2 in the Bornholm Basin to 3260š820 Bq m-2 in the Gulf of Gdansk. Depositions of 239,240Pu in the Bornholm Basin were 28.1-30.4 Bq m-2 and in Gulf of Gdansk 162-174 Bq m-2. The concentration peaks of long-lived radionuclides, owing to the sedimentation processes, show the maximum fallout period in different sediment layers. The observed differences in distribution of radiocaesium and plutonium along the profile confirm two main sources of contamination - Chernobyl fallout for 137Cs and global fallout in case of 239,240Pu. In chosen core samples from the Gdansk Basin vertical distribution of 210Pb concentrations were determined. Evaluated sedimentation rates based on decrease of unsupported 210Pb ranged in the Gdansk Basin from 1.9 to 2.3 mm year-1. Calculations based on 239,240Pu peaks show sedimentation rate, in the range from 1.6-2.2 mm year-1 for P110 region.

16

210 Pb dating of young holocene sediments in High-mountains lakes of the Tatra Mountains

Kotarba A., Łokas E., Wachniew P.

Geochronometria

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2002

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Vol. 21

73-77

EN

Topmost sediments in two oligotrophic lakes of the High Tatra Mountains were studied in terms of sedimentological characteristics and 210 Pb dating. An alpine lake sediments are important source of information on geomorphic process activity in glacial catchments. Two different sediment transfer models are represented. In Morskie Oko lake basin majority of extreme, short lasting geomorphic events triggered on the surrounding slopes are registred in lake sediments (minerogenic laminae), while in Zelene Pleso lake only an effect of pro-longed flooding periods are to be seen. The sedimentation rates in both lakes are similar.

17

Middle Jurassic concretions from Częstochowa (Poland) as indicators of sedimentation rates

Majewski W.

Acta Geologica Polonica

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2000

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Vol. 50, no. 4

431-439

EN

The Częstochowa Clay from south-central Polandcontains numerous carbonate (sideritic and calcitic) concretions. Their sedimentary and diagenetic features allowed determination of the relative progress of diagenesis during their formation. Four categories of concretions are identified using such characteristics as: mineral composition, shape, presence of septarian structures, presence and preservation of macrofossils, evidence of bioerosion and benthic colonization. The concretion types recognized are: (1) early-diagenetic calcite concretions with evidence of reworking (hiatus concretions), (2) early-diagenetic fossiliferous calcite-concretions, (3) early-diagenetic siderite-concretions with septaria, and (4) later early-diagenetic massive siderite-concretions. The reconstruction of early diagenetic environments is based on such factors as: the dynamics of compaction, isolation from oxygenated sea-water, and availability of carbonate ions. All these factors are attributed to changes in the rate of sedimentation. According to the proposed hypothetical mechanisms, the early-diagenetic concretions formed during periods of generally slower sedimentation than the later early-diagenetic bodies.