Wyniki wyszukiwania - Biblioteka Nauki

1

137Cez w środowisku leśnym Opolszczyzny

100%

Dołhańczuk-Śródka A. , Kiczma B. , Majcherczyk T. , Wacławek M.

Chemia i Inżynieria Ekologiczna

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2000

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tom Vol. 7, nr 12

1309-1317

PL

Wykonano pomiary aktywności właściwej 137CS w próbkach gleb leśnych pobranych z terenu Opolszczyzny, głównie z okolic Łambinowic, Olesna i Szumiradu. Aktywność właściwa próbek gleb pobranych z l0-centymetrowej warstwy jest zróżnicowana i mieści się w zakresie (139-2335) Bq/kg s.m. Są to wartości wielokrotnie przewyższające średnią aktywność gleb w Polsce. Porównując badane tereny, największą aktywność właściwą 137CS stwierdzono w okolicach Łambinowic. Ponadto przedstawiono wstępne wyniki badań nad określeniem wpływu właściwości gleb na proces migracji radionuklidu 137CS z naturalnego środowiska glebowego do szaty roślinnej.

EN

Measurements of specific activity of 137Cs made for the samples of soils taken from woods of the Opole region: in Łambinowice, Olesno and Szumirad were presented. Specific activity of soils samples taken from l0-cm layer was different and were limited to the range (139-2335) Bq/kg d.m. The average activity of 137Cs in samples of soils from Opole region are many times bigger than the average activity for soils in Poland. The highest cesium activity has been observed in the samples taken from the Łambinowice region. Preliminary results of the investigations of the influence of soils properties on 137 Cs migration process from soil to plants were shown.

2

Badanie aktywności radiocezu na obszarze transgranicznym polsko-czeskim

100%

Dołhańczuk-Śródka A. , Ziembik Z. , Wacławek M. , Hysplerova L.

Proceedings of ECOpole

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2007

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tom Vol. 1, No. 1/2

113--118

PL

Na skutek awarii reaktora EJ w Czarnobylu do środowiska przedostało się wiele izotopów promieniotwórczych. Skażenia te objęty m.in. terytoria Polski i Czech. W ramach projektu współfinansowanego ze środków Europejskiego Funduszu Rozwoju Regionalnego (Inicjatywa Wspólnotowa INTERREG IIIA Czechy-Polska) przeprowadzono badania, których celem było określenie aktualnych rozkładów terytorialnych depozycji izotopów cezu w powierzchniowej warstwie gleby oraz mocy dawki promieniowania gamma na obszarze transgranicznym polsko-czeskim.

EN

As the result of breakdown of the nuclear power plant in Chernobyl large quantities of radioactive substances were released to environment. Among others the territories of Poland and Czech were contaminated. The aim of the project was investigation of current local depositions of cesium isotopes close to soil surface and total dose of gamma radiation in the Polish - Czech border region. The work was partly supported by European Regional Development Fund (Community Initiative INTERREG IIIA Czech-Poland).

3

Zastosowanie 137Cs do modelowania procesów erozji i akumulacji w obrębie lessowej doliny użytkowanej rolniczo

94%

Poręba G. J.

Landform Analysis

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2008

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tom Vol. 9

369--372

4

Zmienność skażenia cezem-137 środowiska Polski południowo-wschodniej - badania w małej skali

94%

Zgłobicki W.

Przegląd Geologiczny

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2002

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tom Vol. 50, nr 2

135-139

PL

W pracy przedstawiono wyniki badań nad przestrzenną zmiennością skażenia gleb cezem-137. Szczegółowe studia prowadzone były w niewielkiej, rolniczej zlewni położonej w północnej części Wyżyny Lubelskiej. Na podstawie wyników analiz 85 próbek glebowych stwierdzono występowanie znacznego zróżnicowania sumarycznego ładunku izotopu w zlewni. Jako główny czynnik redystrybucji cezu w krajobrazie rolniczym wskazano procesy denudacyjne.

EN

This paper presents the results of studies on the spatial variability of caesium-137 contamination in soils. The detailed studies were conducted within small, agricultural catchment located in northern part of the Lublin Upland. Based on the results .ie rived from the analysis of 85 soil samples, a significant variability of total caesium activity within the catchment was determined. The denudation processes were indicated as a main factor of cesium redistribution within the farming landscape.

5

Anthropogenic radionuclides 137Cs and 90Sr in the southern Baltic Sea ecosystem

94%

Zalewska T. , Suplińska M.

Oceanologia

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2013

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tom No. 55 (3)

485--517

EN

The radioisotopes of caesium (137Cs) and strontium (90Sr) make the greatest contribution to the radioactivity level due to artificial radionuclides in the Baltic Sea, where the level of 137Cs contamination is higher than in any other part of the world ocean. The main sources of man-made radionuclides are the Chernobyl accident in 1986 and the nuclear weapons tests carried out in the 1950s and 1960s. This study discusses the distribution patterns and trends in activity concentrations of 137Cs and 90Sr recorded in various compartments of the marine environment of the southern Baltic Sea. It is based on an investigation of radioactive substances as part of the Polish National Environmental Monitoring Programme. In 2010 the average concentration of 137Cs in the southern Baltic was 35 Bq m-3, while the level of 90Sr in these waters has remained at much the same level in recent years (ca 8 Bq m-3). The distribution of isotopes in the bottom sediments reflect historical events that can be identified in sediment profiles. The activity concentrations of the caesium isotope are the highest in sediments from the Gulf of Gdansk, whereas the least polluted sediments are found in the Bornholm Basin, in the western part of the southern Baltic. The highest concentrations of 137Cs in benthic plants were measured in the red alga Polysiphonia fucoides: 22.3 Bq kg -1 d.w. in June and 40.4 Bq kg-1 in September. These levels were much higher than those found in the bivalve Mytilus trossulus (7.3 Bqkg-1 d.w.). 137Cs concentrations in fish have decreased in time, reflecting the trends recorded in seawater. In 2010 the respective 137Cs activities in Clupea harengus, Platichthys flesus and Gadus morhua were 4.7, 4.9 and 6.6 Bq kg-1w.w.

6

Zawartość 137 Cs w wybranych gatunkach ryb słodkowodnych po awarii w Czarnobylu

94%

Kwapuliński J. , Majchrzyk H. , Wiechuła D. , Loska K.

Problemy Ekologii

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1998

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tom R. 2, nr 4

140-145

PL

W pracy przedstawiono dynamikę zmian 134Cs, 137Cs w niektórych gatunkach ryb zebranych ze zbiorników na terenie południowej Polski. Wyniki porównano z radioaktywnością beta i zawartością radiocezu w opadzie całkowitym, wodzie i osadzie dennym. Badania przeprowadzone w okresie 1983-1992 wykazały zróżnicowaną gatunkowo zdolność do kumulacji radiocezu przez ryby oraz jego wysoki wzrost po awarii.

EN

The dynamic of change of 134, 137Cs content in some fish species from reservoirs of southern Poland have been presented in this paper. The results were compared with beta-radioactivity and radioactive caesium content in the total precipitation, in the water and bottom sediment. The studies conducted between 1983 and 1992 showed diversity in radio caesium accumulation in different fish species, and that its total level had increased distinctively after the accident.

7

Caesium-137 as a soil erosion tracer: a review

94%

Poręba G. J.

Geochronometria

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2006

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tom Vol. 25

37-46

EN

This paper describes a method of soil erosion and soil movement measurements using 137Cs as a tracer. This technique has been used successfully employed for more than 30 years. Caesium-137 is a valuable tracer to study soil erosion. Its chemical and biological movement in soil is limited. Practically all redeposition of caesium-137 in soil after fallout occurs with soil particles due to strong fixation of caesium onto soil particles. This technique overcomes many problems of the traditional techniques to study soil erosion. First of all, this technique gives quantitative results of soil erosion and deposition for the medium-term (about 40 years). Moreover, these results are possible to obtain in a relatively short time compared to the traditional methods. The 137Cs method to obtain quantitative value of soil erosion and deposition requires the availability of undisturbed sites to obtain the reference value of 137Cs fallout for the study area and a numerical relationship. Currently, there are many calibration relationships available and the calculation of the soil erosion from 137Cs activity data strongly depends on the chosen relationship and the parameters that were used for a particular model.

8

Recent changes in sediment accumulation rates in Adventfjorden, Svalbard

94%

Zajączkowski M. , Szczuciński W. , Bojanowski R.

Oceanologia

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2004

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tom No. 46 (2)

217-231

EN

Recent sediment accumulation rates in Adventfjorden (Svalbard), a small subpolar fjord, were determined by 210Pb and 137Cs dating. Modern rates in the central basin decrease downfjord from 1.87 to 0.87 cm y-1 (2.6 to 1.19 g cm-2 y-1). Comparison of the modern values (1986-2001) with older ones (1963-86) reveals a marked increase in sediment accumulation rates in the last ten years. This correlates well with recent climate changes (warming and increase in precipitation). Comparison with particulate matter flux data indicates that a portion of the sediment is passed on to Isfjorden.

9

Migration of radiocaesium in individual parts of the environment

94%

Čipáková A.

Nukleonika

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2005

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tom Vol. 50,suppl.1

19-23

EN

The aim of this study was to compare the amount of radiocaesium in chosen compartments of environment in two localities of Košice vicinity (Košice and Jasov). Prevailing part of radiocaesium is in the upper layer of soils and specific activity of 137Cs in the first layer for locality Jasov in 2001 achieved 21.49 Bq.kg 1. Transfer factor values estimated for mixed grasses and for individual years varied within the range of 0.22 to 0.56 at locality Košice and of 0.09 to 0.19 at locality Jasov. On the base of results from modified Tessier sequential extraction method we determined that more than 50% of this radionuclide is in the soil in not extractable fraction. From studied species of mushrooms in sample of Rozites caperata the specific activity achieved 1822.0 Bq.kg 1 d.w.

10

Estimation of radioactivity dose rate absorbed with ingested foods

84%

Dołhańczuk-Śródka A. , Ziembik Z.

Ecological Chemistry and Engineering. A

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2013

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tom Vol. 20, nr 9

991--1008

EN

The purpose of the study was to estimate the effective dose of ionising radiation absorbed in consequence of consuming the selected food products for relevant age groups and estimation of the resulting risk. The study was carried out with the use of food products, part of which was produced in the area contaminated with 137Cs released after the Chernobyl Nuclear Power Plant explosion. On the basis of the obtained study results, it can be stated that in consequence of consumption of the selected food products, people may receive increased radiation doses from artificial radioactive isotopes, which are one of the components of the annual effective dose. Taking into consideration other sources of ionising radiation, which are not present in food, one should assume that 137Cs contained in food has a little share in the total radiation dose absorbed by the inhabitants of the studied region.

PL

Celem tego badania było określenie skutecznej dawki promieniowania jonizującego, pochłoniętej wskutek spożywania wybranych produktów żywnościowych. W ocenie ryzyka uwzględniono grupy wiekowe ludności. Badania przeprowadzono z wykorzystaniem produktów spożywczych, z których część została wyprodukowana na obszarach skażonych 137Cs, uwolnionym po wybuchu elektrowni jądrowej w Czarnobylu. Wyniki przeprowadzonych badań potwierdzają zwiększenie dawki promieniowania, pochodzącej od sztucznych izotopów promieniotwórczych. Biorąc pod uwagę inne niż żywność źródła promieniowania jonizującego, można stwierdzić, że 137Cs zawarty w artykułach spożywczych ma mały udział w całkowitej dawce promieniowania pochłoniętego przez mieszkańców badanego regionu.

11

Spatial variation of cesium 137Cs and natural radionuclides activities in forest and field soil localities of the Opole anomaly area by means of laboratory and field gamma-spectrometric measurements

84%

Litorowicz M. , Majcherczyk T. , Solecki A. , Wacławek W.

Chemia i Inżynieria Ekologiczna

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2004

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tom Vol. 11, nr 12

1333--1343

EN

Field gamma-spectrometric mapping in the area of the Opole post-Chernobyl anomaly by means of portable RUM-1 gamma-spectrometer and simultaneous sampling of soil profiles in selected points has been performed. Collected samples analyzed both by Canberra gamma-spectrometer with HPGe detector and RUM-1 with Nal(T1) detector yielded data necessary to calibrate the second one. Results of the soil profile sampling were calculated in surface activity of cesium 137Cs (Bq/m2) what after correlation with field gamma-spectrometric measurements enabled calibration of RUM-1 for field surface activity measurement. The relationship between spatial distribution 137Cs and other natural radionuclides (40K and U, Th series) in soil profiles was analyzed. Obtained results indicate that in the case of natural radionuclides their vertical distribution in the soil profile is more of less random and homogenous not only in cultivated field but also in the forest area. 137Cs vertical distribution in forest profiles exhibits definitely downward exponential decrease pattern characteristic for slow and limited migration of this radionuclide. The maximum value is as high as 2956 Bq/kg in the topmost soil layer. In the case of cultivated soill 137Cs vertical distribution is random and homogenous varying in the range of 105-58 Bq/kg what can be explained by mechanical mixing of soil during agricultural activity. Total 137Cs activity in 0.3 m profile of cultivated field is lower that in the case of both forest localities, but does not differ significantly from the lower forest result. Field gamma-spectrometric measurements performed by means of portable RUM-l gamma-spectrometer were found to be well correlated with total cesium activity established by sampling of the first 0.15 m thick layer of soil. Correlation coefficient is significantly lower when activities in deeper soil horizon are taken into account.

PL

Zbadano zmienność przestrzenną aktywności 137Cs i naturalnych radionuklidów (4oK oraz radionuklidów szeregów U, Th) w leśnych i polnych profilach glebowych anomalii Opola w okolicach wsi Lipowa. Uzyskane wyniki wskazują, że w przypadku naturalnych radionuklidów rozkład w profilu pionowym jest przypadkowy i jednorodny zarówno w lesie, jak i na polu. Aktywność cezu 137Cs w leśnych profilach glebowych maleje wykładniczo, co jest charakterystyczne dla powolnej i ograniczonej migracji tego radionuklidu. Maksymalna aktywność wynosi 2956 Bq/kg w powierzchniowej warstwie gleby. W przypadku użytkowanych rolniczo gleb rozkład 137Cs w pionie jest w marę jednorodny i jego aktywność zmienia się w zakresie od 105-58 Bq/kg, co może być wyjaśnione mechanicznym mieszaniem w czasie zabiegów agrotechnicznych (orki). Wykazano przydatność gamma-spektrometru RUM-l współpracującego z sondą SSU-3-2 z detektorem NaI/T1 zarówno do laboratoryjnych, jak i terenowych pomiarów aktywności cezu 137Cs. Porównanie wyników pomiarów terenowych z laboratoryjnymi analizami próbek pobranych do głębokości 0,30 m wykazało, że terenowe zdjęcie gamma-spektrometryczne dobrze koreluje się z sumaryczną aktywnością w powierzchniowej warstwie gleby do głębokości 0,15 m. Korelacja ta jest znacznie gorsza w przypadku warstwy sięgającej 0,20 m.

12

Transfer of cesium-137 from forest soil to moss Pleurozium schreberi

84%

Dołhańczuk-Śródka A. , Ziembik Z. , Wacławek M. , Hysplerova L.

Ecological Chemistry and Engineering. S

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2011

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tom Vol. 18, nr 4

509-516

EN

Moss (Pleurozium schreberi) and soil samples collected in 2009 in Bory Stobrawskie forest were used to study the transfer factor (TFCs) and aggregated transfer factor (Tag) of radiocesium from forest soil to moss. This investigation also included determination of 40K activity, pH, conductivity and organic matter content in soil. The mean 137Cs activities were 179 Bq/kg d.m. in soil samples and 203 Bq/kg d.m. in moss. The TFCs of 137Cs from soil to moss was varied in the range from 0.1 to 3.3. The mean surface activity was 11.2 kBq/m2. The Tag values were limited in the range from 0.001 to 0.058. Additionally the TFK values for 40K were computed. It was found that the main contribution of 137Cs activity in environment originates from soil and activities of 137Cs and 40K were usually higher in moss than in soil. It can be supposed that the 137Cs isotope migrates to moss from its surrounding. Among others, tatistically significant correlation between TF of 137Cs and activity of 40K in soil was found. Low activity of 40K in soil is conducive to the transfer of cesium to moss. The organic matter content also affects transport of cesium and potassium between moss and soil.

PL

Mech (Pleurozium schreberi) i próbki gleby pobranej w 2009 roku w Borach Stobrawskich wykorzystywano do badania współczynnika transferu (TFCs) i zbiorczego współczynnika transferu (Tag) radiocezu z gleb leśnych do mchu. Określono także aktywność 40K, pH, konduktywność i zawartość materii organicznej w próbkach gleby. Średnia aktywność 137Cs wynosiła 179 Bq/kg s.m. w próbkach gleby i 203 Bq/kg s.m. w próbkach mchu. Współczynnik transferu TFCs z gleby do mchu zmieniał się w zakresie od 0,1 do 3,3. Średnia aktywność powierzchniowa wynosiła 11,2 kBq/m2. Wartości Tag mieściły się w zakresie od 0,001 do 0,058. Zostały także obliczone wartości TFK dla 40K. Stwierdzono, że główny udział aktywności 137Cs w środowisku pochodzi z gleby, a aktywności 137Cs i 40K były zwykle większe w mchu niż w glebie. Znaleziono istotną statystycznie korelację pomiędzy TFCs i aktywnością 40K w glebie. Sugeruje to, że mała zawartość potasu w glebie sprzyja przenoszeniu cezu do mchu. Zawartości materii organicznej również wpływają na transport cezu i potasu pomiędzy mchem i glebą.

13

Specjacja radionuklidu 137Cs w glebach

84%

Niesiobędzka K.

Chemia i Inżynieria Ekologiczna

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2000

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tom Vol. 7, nr 3

237--247

PL

W celu oceny biodostępności radionuklidu 137Cs uwolnionego w wyniku awarii elektrowni jądrowej w Czarnobylu przeprowadzono analizę specjacyjną zgodnie ze schematem sekwencyjnej ekstrakcji Tessiera, obejmującym pięć frakcji: frakcję jonowymienną, węglanową, organiczną, związaną z tlenkami żelaza i manganu oraz frakcję pozostałościową. Mobilne formy cezu określono według metody zaproponowanej przez Pavlotskovą. Próbki gleb pobierano w latach 1995-1996. Aktywność radiocezu mierzono metodą gammaspektrometryczną.

EN

The bioavailability of raidionuclide 137Cs derived from the Chernobyl is discussed in terms of it speciation in soils. The sequential extraction scheme proposed by Tessier was used in speciation of radiocaesium in soils. This scheme includes five fractions: exchangeable, bound to carbonates, bound to iron and manganese oxides, bound to organic matter and residual fraction. Mobile forms of caesium was evaluated by Pavlotskaya Method. Samples of soils were collected in the period from June 1995 to July 1996. The radiocaesium activity were determined by gamma spectrometry.

14

Preliminary evaluation of14C and36Cl in nuclear waste from Ignalina Nuclear Power Plant decommissioning

83%

Mažeika J. , Lujanienė G. , Petrošius R. , Oryšaka N. , Ovčinikov S.

Open Chemistry

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2015

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tom 13

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nr 1

EN

On a first attempt, the determination of 14C and 36Cl activity concentrations in basic operational waste (spent ion-exchange resins and perlite mixture), in decommissioning waste (construction concrete, sand, stainless steel and serpentinite) and irradiated graphite from the Ignalina NPP has been performed. The samples for measurement of the specific activity of 14C and 36Cl were obtained from the selected places, where the highest values of the dose rate and the activity concentrations of gamma emitters were found. The performed study of the total 14C and 36Cl activity concentrations was based on estimated chemical forms of 14C (inorganic and organic compounds) and 36Cl as Cl- ion. The tested methods used in this study were found to be suitable for estimation of activity concentrations of measured radionuclides.

15

Influence of urea and of chlorocholine chloride on accumulation of 137Cs in spring wheat crops

83%

Hryńczuk B. , Weber R.

Nukleonika

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2000

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tom Vol. 45, nr 2

133-135

EN

The influence of leaf feeding with nitrogen in urea solution and application of chlorocholine chloride (CCC) on the uptake of 137Cs by spring wheat from the investigated soil samples and through leaves was studied in pot experiments. Spray application of nitrogenous fertilizer in urea solution with additional use of growth retardant were found to have brought about an increased accumulation in the grain of 137Cs taken up by the plants from the contaminated soil. It was found that 2–4 times more 137Cs accumulated in wheat grain from leaves contaminated in the flowering stage in comparison with that found in the grain of plants contaminated in the propagation stage. The application of leaf feeding with urea and chlorocholine exerted no influence on the accumulation of 137Cs in grain if the plants had been contaminated superficially in their earlier development stages. Contamination with 137Cs sprayed upon the plants after application of chlorocholine chloride appeared to pass to the spring wheat crops more readily.

16

Bioaccumulation of 137Cs in wild mushrooms collected in Poland and Slovakia

83%

Bazała M. , Bystrzejewska-Piotrowska G. , Čipáková A.

Nukleonika

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2005

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tom Vol. 50,suppl.1

15-18

EN

Activities of caesium in the mushrooms collected at different localities in Poland and Slovakia have been compared. Discrimination factor, defined as [(Bq.kg 1 137Cs in caps)/(Bq.kg 1 40K in caps)]/[(Bq.kg 1 137Cs in stipes)/ (Bq.kg 1 40K in stipes)], was used to explain mechanisms of uptake and transport of radiocaesium in fungi. The collected specimens were divided into caps and stipes. Activities of 137Cs and 40K were measured using a multichannel gamma spectrophotometer with HPGe(Li) detector. The highest accumulation of 137Cs was found in the samples of Xerocomus badius, Suillus luteus and Tricholoma equestre (2.7, 1.9 and 1.2 kBq.kg 1, respectively). T. equestre and S. luteus proved to hyperaccumulate caesium since 137Cs levels in the caps were two orders of magnitude higher than in the soil while only one order higher in the case of X. badius. Transport of 137Cs from stipe to cap in fruitbody is directly related to K concentration with lack of similar dependence in the case of transport from soil to cap. There is no dependence between activity of 137Cs in the analyzed fruitbodies and its activity in the soil, which makes mushrooms controversial bioindicators

17

Assessment of the influence of soil properties on 137Cs accumulation in Of horizon in forest soils

83%

Ziembik Z. , Dołhańczuk-Śródka A. , Wacławek M.

Nukleonika

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2010

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tom Vol. 55, No. 2

205-212

EN

The work focuses on assessment of soil physicochemical parameters influence on 137Cs accumulation in Of soil horizon. Besides organic matter content and pH, the parameters related to sorption properties and mobile ions concentration were considered. The data were transformed using Box-Cox formula. To find mutual relationships between variables cluster analysis (CA) and principal components analysis (PCA) were used. It was found that the transformed physicochemical parameters in Of horizon are more or less related with each other but no linear or nearly linear relationships between 137Cs activity and physicochemical parameters were found.

18

Radionuclides 137Cs and 40K in the soils of the Tatra National Park (TPN, Poland)

83%

Kubica B. , Skiba S. , Drewnik M. , Stobiński M. , Kubica M. , Gołaś J. , Misiak R.

Nukleonika

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2010

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tom Vol. 55, No. 3

377-386

EN

The paper presents the results of radioactivity determination of artificial 137Cs and natural 40K in soil samples taken from the Tatra Mountains in Poland (Tatra National Park – TPN). Soil samples were collected as the cores of 10 cm in diameter and 10 cm in depth. These cores were divided into 3 slices. It has been found that the content of 137Cs was the highest at the sites of the altitude over 1300 m a.s.l. The values of 137Cs concentration in the soils examined varied – from 55.8 Bqźkg–1 (dry mass) (417.8 Bqźm–2) for the Tomanowa Pass (1685 m a.s.l.) to 5111 Bqźkg–1 (dry mass) (8400 Bqźm–2) for the Krzyzne Pass (2112 m a.s.l.). In most cases, the values were lower than the average radiocaesium concentration established for Poland.

19

Application of 239,240 Pu, 137Cs and heavy metals for dating of river sediments

83%

Ciszewski D. , Łokas E.

Geochronometria

|

2019

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tom Vol. 46, no. 1

138--147

EN

The periodical nature of overbank sediment accumulation makes their detailed dating much more difficult than dating sediments in water reservoirs. To improve the commonly used dating with 137Cs, we combined this method with Pu isotopes and heavy metals in order to date sediments of the Chechło River (southern Poland), which was polluted by a lead-zinc mine. We analyzed 137Cs, Pu isotopes and heavy metal concentrations in three profiles of overbank sediments and in two profiles of subsidence basins in the lower river reach. The results indicate a lower accuracy and higher uncertainty of the overbank than the dating of reservoir sediments. The application of plutonium isotopes provided very important information validating caesium peaks or providing the principal information regarding horizons dated with heavy metals. The obtained dates give the earliest possible age of particular horizons with the actual sediment deposition delayed by several to a dozen years. This investigation shows that using plutonium radioisotopes can be a useful tool for dating, particularly of the youngest overbank sediments where numerous sedimentation gaps cause uncertainties in the application of other methods, e.g. radiocaesium and heavy metals.

20

Sedimentation rates in the Lake Qattinah using 210Pb and 137Cs as geochronometer

83%

Alhajji E. , Ismail I. M. , Al-Masri M. S. , Salman N. , Al-Haleem M. A. , Doubal A. W.

Geochronometria

|

2014

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tom Vol. 41, no. 1

81--86

EN

The constant rate of supply (CRS) of excess 210Pb model was successfully applied to assess 210Pb data of two sediment cores from the lake Qattinah, Syria. Gamma spectrometry was used to determine 137Cs and 210Pb activity concentrations. The bottom of the cores was 210Pb-dated to years 1907 and 1893. The accumulation rates were determined using 210Pb method and found to vary similarly in both cores from 0.10 ± 0.01 to 3.78 ± 0.57 kg m-2 y-1 during the past century. 137Cs was used as an independent chronometer. The two distinct peaks observed on the 137Cs record of both cores, corre-sponding to 1965 and 1986, have allowed a successful validation of the CRS model.