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Coastal cliff erosion as a source of toxic, essential and nonessential metals in the marine environment

Bełdowska Magdalena, Bełdowski Jacek, Kwasigroch Urszula, Szubska Marta, Jędruch Agnieszka

Oceanologia

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2022

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No. 64 (4)

553--566

EN

Due to the rising environmental awareness, emissions and releases of pollutants, including metals, have been considerably reduced in the last decades. Therefore, the remobilization of natural and anthropogenic contaminants is gaining importance in their biogeochemical cycle. In the marine coastal zone, this process occurs during the erosion of a shore, especially the most vulnerable cliffs. The research was conducted in the Gulf of Gdańsk (southern Baltic Sea) from 2016 to 2017. The sediment cores were collected from four cliffs; additionally, marine surface sediments were also taken. The concentrations of essential (Cr, Mn, Fr, Cu, Zn) and nonessential (Rb, Sr, Y, Zr, Ba) metals were analyzed using the XRF technique. The levels of the analyzed metals were relatively low, typical of nonpolluted areas. However, considering the mass of eroded sediments, the annual load of metals introduced into the sea in this way is significant. In the case of Cu, Zn, and Y the load can amount to a few kilograms, for Cr and Rb – over ten kilograms, for Mn, Sr, and Zr – several tens of kilograms, for toxic Ba – over 100 kg, and in the case of Fe – 4.8 tonnes. During strong winds and storms, when the upper part of a cliff is eroded, especially the load of Zn and Cr entering the sea may increase. The content of Cr, Zr, and Ba in the cliffs was higher compared to marine sediments from the deep accumulation bottom, which indicates that coastal erosion may be an important source of these metals.

2

Application of the ERT to recognise the geological structure of frost‑riven cliffs localised in the Skalny Potok (Hrubý Jeseník Mts.)

Stan-Kłeczek Iwona, Stan Dominika

Acta Geophysica

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2019

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Vol. 67, no. 6

1759--1764

EN

In the area of the Skalni Potok Nature Reserve (Hrubý Jesenik), studies of gneissic cliffs were carried out to determine the role of lithology in the process of their formation. The research included geometric measurements of vertical discontinuity zones of selected rock outcrops and the electrical resistivity tomography (ERT) measurements of strongly weathered subsurface layers. As a result of the measurement, the orientation of the main crack systems (NW–SE and NE–SW) responsible for the location of cliffs within the Skalni Potok Valley was obtained. In addition, the main crack directions for the gneiss occurring in the studied mountain region were identified. Interpretation of the ERT models allowed to characterise the structure of the rock mass, including the reach of the rainwater infiltration level and the depth of the weathering front.

3

A new approach of coastal cliff monitoring using mobile laser scanning

Ossowski R., Tysiąc P.

Polish Maritime Research

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2018

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nr 2

140--147

EN

The article proposes a new approach of coastal cliff monitoring which bases on a new comprehensive monitoring system, being a combination of mobile scanning from the sea with the geotechnical stability analysis. Mobile laser scanning is an innovative solution for 3D data collection which allows the monitored object geometry to be precisely measured, thus providing opportunities for series of analyses contributing to the development of an improved monitoring system. The authors present selected cliff profiles obtained from mobile scanning in the area of Jastrzebia Gora, complemented by relevant geotechnical analyses. The analysis of current cliff geometry is accompanied by calculations of hypothetical cliff profile changes resulting from possible action of nature forces. Finally, a comprehensive strategy for coastal cliff monitoring is proposed.

4

Stratygrafia i litologia mineralnych osadów występujących w klifach środkowej części polskiego wybrzeża Bałtyku

Olszak I. J., Florek W., Seul C., Majewski M.

Landform Analysis

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2008

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Vol. 7

113--118

PL

Korzystając z dawnych i nowych opracowań geologicznych oraz własnych danych petrograficznych i stratygraficznych, autorzy przedstawili swoje poglądy na temat litologii i wieku osadów mineralnych budujących klify pomiędzy Jarosławcem a Dębiną. Najnowsze dane odbiegają od zakorzenionych w literaturze poglądów.

EN

New views about lithology and age of deposits building coastal cliffs between Jarosławiec and Dębina, diverging from the models rooted in the literature, are presented by the authors. The revision is based on critical re-assessment of older and more recent geological reports and new results of petrological and stratigraphic research. The oldest glacial deposit exposed in cliff sections is grey till. Petrological data and TL dating results indicate clearly that it was deposited during the Świecie stadial. At Jarosławiec site, the till is enriched in Tertiary organic material and divided into two layers based on colour. However, petrology and TL age determinations do not differ between these layers. In the cliffs investigated, as well as in the other coastal cliffs in the eastern Pomorze region, older tills do not occur. Likewise, tills from the main stage of the last glaciation have not been recognized. The Świecie stadial till is overlain by outwash, glacilimnic and limnic deposits, the latter dated for the Grudziądz interstadial. Almost everywhere the near-surface layer is built of late Holocene aeolian sand with palaeosols.

5

Geological structure of the southern Baltic coast and related hazards

Uścinowicz Sz., Zachowicz J., Graniczny M., Dobracki R.

Polish Geological Institute Special Papers

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2004

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Vol. 15

61-68

EN

Polish coast of the Baltic Sea has a total length of 498 km (without internal lagoons coasts). Quaternary deposits dominate coastal zone, similar to central and northern Poland. According to morphology and geological structure, three types of coast are distinguished: cliffs (c. 101 km), barriers (380 km) and coast similar to wetlands (salt marshes) (c. 17 km). Generally, three types of mass movements can be distinguished on cliff coast: eboulements (rock falls) dominated on the cliffs built mainly by tills, talus and landslip, dominated on sandy cliffs, and typical landslides occurred on cliff stretches with a complex structure where the main role play clay layers being initial slide layers for other deposits. Serious risks are related to erosion of low and narrow barriers, which could be easy broken during storm surges. Storm floods in case of barrier being broken threaten lowlands behind the barriers. Similar flood hazard exists also on lagoon coasts located behind large and relatively stable barriers. It is caused by barographic high water stands, which in extreme cases reach up to 2 m above the mean sea level, and water back flow into straits connecting lagoons with the sea.

PL

Długość polskiego wybrzeża morskiego wynosi 498 km (bez linii brzegowej Zalewów Wiślanego i Szczecińskiego). W budowie geologicznej strefy brzegowej, podobnie jak środkowej i północnej Polski, dominują osady czwartorzędowe. Biorąc pod uwagę geomorfologię i budowę geologiczną wyróżniono trzy zasadnicze typy wybrzeży: klify o łącznej długości ok. 101 km, wybrzeża wydmowe (mierzeje) o łącznej długości ok. 380 km oraz wybrzeża nizinne typu Wetland o długości ok. 17 km. Na wybrzeżach klifowych wyróżniono trzy typy ruchów masowych: obrywy dominujące na klifach, w których występuje glina zwałowa, zsuwy i osypiska dominujące na klifach zbudowanych głównie z osadów piaszczystych oraz typowe osuwiska występujące na klifach o złożonej strukturze geologicznej, gdzie główną rolę odgrywają warstwy ilaste będące powierzchnią poślizgu dla warstw wyżej ległych. Poważne zagrożenia związane są też z erozją niskich i wąskich mierzei, które łatwo mogą być przerwane w czasie sztormów. Nisko położone obszary zaplecza mierzei w takim wypadku zagrożone są powodziami sztormowymi. Podobne zagrożenia powodziowe istnieją też na zapleczu mierzei relatywnie stabilnych - szerokich z wysokimi wałami wydmowymi. Powodzie mogą wystąpić w przypadku wysokich stanów wody spowodowanych spiętrzeniami sztormowymi i barycznymi, dochodzącymi maksymalnie do 2 m ponad średni poziom morza, kiedy dochodzi do wlewów wód morskich do Zalewów i jezior przybrzeżnych.