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1

Calculation of Dune Profile Changes Generated by Hurricane: Preliminary Results

Szmytkiewicz P., Szmytkiewicz M., Schönhofer J., Morawski J., Malicki J.

Archives of Hydro-Engineering and Environmental Mechanics

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2018

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Vol. 65, nr 3

221--239

EN

The paper presents the main theoretical concepts related to methods of calculating the erosion rate for sandy dunes on natural coasts, namely, the beach equilibrium profile and incident waves. To illustrate calculations of dune erosion in the vicinity of the Coastal Research Station (CRS) in Lubiatowo, the Xbeach model (an incident wave model) was used. The calculations were carried out for hydrological and hydrodynamic conditions that accompanied Hurricane Ksawery (December 6–8, 2013). The results of the calculations were compared with the measured data. A satisfactory agreement was obtained between the predicted and measured results.

2

An aeolian or a glaciolacustrine record? A case study from Mieļupīte, Middle Gauja Lowland, northeast Latvia

Nartišs M., Kalińska-Nartiša E.

Geologos

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2017

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Vol. 23, No. 1

15--28

EN

In the Middle Gauja Lowland, northeast Latvia, dunes are distributed over a vast glaciolacustrine plain that formed during the retreat of the Fennoscandian ice sheet. Such a direct contact between aeolian and glaciolacustrine sediments can be used to infer depositional settings and decipher to what extent these sediments bear an aeolian component. Our proxies, although preliminary, reveal a limited range of variation in grain-size parameters, a significant presence of quartz grains with silica precipitation and matt-surface grains of various rounding degrees and massive structure combined with horizontal lamination. These are indicative of periglacial-aeolian depositional conditions in the foreland of the Linkuva ice-marginal zone. Sedimentary characteristics do not match a single luminescence date of 9.2±0.6 ka, which significantly postdates the minimum age of the Linkuva ice-marginal zone with 10Be ages between 15.4 and 12.0 ka. Whether deposition started directly after drainage of the Middle Gauja ice-dammed lake or if there is a gap of 2.8–6.2 ka is a matter of debate; only future studies at higher OSL resolution could resolve this.

3

State of shore and backshore on the basis of monitoring results for selected polish seashores

Boniecka H., Kaźmierczak A.

Biuletyn Instytutu Morskiego w Gdańsku

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2015

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Vol. 30, No. 1

150--163

EN

Aim of works on morphology and morphometry of the coastal zone is identification of qualitative and quantitative changes in the beach-dune strip and in the shoreface in conditions of their natural and anthropogenic transformations. As shore and backshore are essential elements reducing risks from the sea to the adjacent hinterland, this article focuses on evaluation of their parameters. Moreover, elements of the coast are described herein in detail. The research material used for the purposes of this article were records of bathymetric-tacheometric measurements of the Polish coast, made at consistent profiles evenly spaced every 500 m. The measurements did not cover the areas adjacent to the Bay of Gdańsk or the Lagoons. This article presents an analysis of the measurements of components of the coastal zone, which covered four morphodynamical areas (the Hel Peninsula, Jastrzębia Góra – Jarosławiec, Jarosławiec – Sarbinowo, and Sarbinowo – Międzyzdroje), twelve sandbar stretches (the Helska, Karniewska, Sarbska, Łebska, Długie, Gardno, Wicko, Kopań, Bukowo, Jamno, Resko, and Dziwnowska Spits) and thirteen cliff stretches (the cliffs in Chłapowo, Jastrzębia Góra, Rowy, Dębina, Ustka, Jarosławiec, Wicie, Sarbinowo, Ustronie Morskie, Śliwin, Trzęsacz, Pobierowo, and on Wolin Island). The basic linear parameters of the beach-dune and beach-cliff belt were read from 678 printouts of tacheometric profiles. A detailed analysis carried out in this manner made it possible for the endangered sections of the coast to manifest themselves. The obtained data are a basis for further comparative analyses, and assessment of the shore under conditions of implementation of the Act on the Protection of Sea Coasts.

PL

Celem prac nad morfologią i morfometrią strefy brzegowej jest poznanie jakościowych i ilościowych zmian zachodzących w pasie plażowo-wydmowym i na podbrzeżu w warunkach ich naturalnych i antropogenicznych przekształceń. W artykule skupiono się na ocenie parametrów brzegu i nadbrzeża, jako znaczących elementów redukujących zagrożenie przyległego zaplecza od strony morza. Ponadto opisano szczegółową charakterystykę elementów wybrzeża. Materiałem badawczym były zapisy pomiarów batymetryczno-tachimetrycznych polskiego wybrzeża, w stałych profilach rozmieszczonych co 500 m. Pomiary nie objęły swoim zasięgiem obszarów przylegających do Zatoki Gdańskiej czy zalewów. W artykule przedstawiono analizę pomiarów elementów strefy brzegowej, które objęły cztery rejony morfodynamiczne (Półwysep Hel, Jastrzębia Góra- -Jarosławiec, Jarosławiec-Sarbinowo oraz Sarbinowo-Międzyzdroje), dwanaście odcinków mierzejowych (Helska, Karniewska Sarbska, Łebska, Długie, Gardno, Wicko, Kopań, Bukowo, Jamno, Resko i Dziwnowska) i trzynaście odcinków klifowych (chłapowski, jastrzębski, rowski, dębski, ustecki, jarosławiecki, wicki, sarbinowski, ustroniomorski, śliwiński, trzęsacki, pobierowski i woliński). Na wydrukach 678 profili tachimetrycznych odczytano podstawowe parametry liniowe pasa plażowo-wydmowego i plażowo-klifowego. Tak przeprowadzona szczegółowa analiza wybrzeża pozwoliła na uwidocznienie zagrożonych odcinków. Uzyskane dane stanowią podstawę do dalszych analiz porównawczych i oceny stanu brzegu w warunkach wdrażania zapisów ustawy o ochronie brzegów morskich.

4

Zastosowanie „korekty efektu wygładzenia” w badaniach form geomorfologicznych

Zarychta A., Zarychta R.

Archiwum Fotogrametrii, Kartografii i Teledetekcji

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2013

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Vol. Spec.

119--132

PL

Intensywne, wręcz rabunkowe wydobycie kruszyw naturalnych – m.in. piasków stosowanych do celów przemysłowych przyczynia się do znaczących zmian w krajobrazie. Na uwagę zasługuje teren województwa łódzkiego – w tym gmina Kobiele Wielkie, w granicach której odnotowano postępującą degradację wydmy parabolicznej na skutek intensywnej eksploatacji czwartorzędowych piasków do celów budowlanych. Rabunkowa działalność gospodarcza człowieka spowodowała, a także nadal powoduje zanik pierwotnego zasięgu i kształtu wspomnianej formy geomorfologicznej. Stąd autorzy niniejszego opracowania za główny cel przyjęli odtworzenie fizjonomii wydmy parabolicznej (sprzed okresu eksploatacji) z wykorzystaniem metod geostatystycznych (w tym krigingu zwyczajnego). Przeprowadzone liczne rekonesanse terenowe miały na celu analizę i ocenę aktualnego stanu formy eolicznej oraz oszacowanie jej dawnego kształtu i zasięgu z wykorzystaniem odbiornika GPS. Z uwagi na uzyskaną niewielką liczbę punktów próbkowania utworzony hipotetyczny trójwymiarowy model badanej wydmy metodą krigingu zwyczajnego – punktowego nie przyniósł zadowalających efektów. Niemniej jednak zastosowanie korekty efektu wygładzenia zaproponowanej w 2005 r. przez J.K. Yamamoto pozwoliło na sporą redukcję powstałego „efektu zafałszowania”. W konsekwencji odtworzony kształt i zasięg analizowanej formy wyraźnie różni się od wyjściowego modelu cyfrowego. Uzyskane wyniki, a w związku z tym idealnie dopasowane wariogramy świadczą o prawidłowo wykonanej analizie geostatystycznej, a tym samym o dużej wiarygodności zbudowanego Numerycznego Modelu Terenu.

EN

Intensive exploitation of natural environment resources, including natural aggregates – among them sand used for industrial purposes e.g. building industry, production of glass or backfilling contributes to significant physiocenotic changes. Concerning the problem, the area of Łódź voivodeship merits attention, especially Kobiele Wielkie commune (Dudki village) where progressive degradation of a parabolic dune occurs. It is caused by excessive extraction of Pleistocene fluvioglacial sand for building purposes. Overexploitation of natural resources has already caused and it is still causing decrease of the primary range and form of the discussed geomorphological form. Therefore, the authors of the paper decided to aim at reconstruction of the physiognomy (of the period prior to extraction) of the dune which had been formed in Dudki village. Geostatistical methods, including ordinary kriging, have been applied for the purpose. The lack of archival cartographic materials of the investigated area made the authors go on numerous field trips which goal was to analyse and estimate the current state of the aeolian form and to determine its shape and range by means of a GPS receiver. A hypothetical three-dimensional model of the investigated dune made by application of an ordinary kriging method has not brought satisfying effects. Too many overestimated and underestimated values of altitude values caused significant generalisations resulting in smoothing of the whole model. Application of the correction of the smoothing effect proposed by J. K. Yamamoto in 2000 enabled considerable reduction of the “falsification effect”. Therefore, the reconstructed shape and range of the dune is considerably different from the one obtained at the initial stage of the investigation by means of the digital model. The obtained results of the correction of the smoothing effect giving in result perfectly matching variograms prove properly performed geostatistical analysis. Hence, despite the lack of cartographic materials showing the state of the dune prior to the extraction (which could have been compared with the obtained results of desktop studies) it has been assumed that the reconstructed model of the dune matches its previous physiognomy and therefore it is the most suitable.

5

Sytuacja morfologiczna i geologiczna teras w Żuławce Małej koło Osieka nad Notecią

Nowaczyk B.

Landform Analysis

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2011

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Vol. 16

124-127

EN

In the study the morphology of Noteć-Warta Parolina (streamway) in the vicinity of Osiek upon Noteć and lithology of floodplain nearby the archaeological site in Żuławka Mała are presented. The genesis of identified forms i also show. The attempt of the age determination of the flooded dune in floodplain biogenic deposits is given

6

SWAT.nz: New-Zealand-based “Sand Waves and Turbulence” experimental programme

Coleman S. E., Nikora V. I., Melville B. W., Goring D. G., Clunie (Dougal) T. M., Friedrich H.

Acta Geophysica

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2008

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Vol. 56, no. 2

417-439

EN

The SWAT.nz ("New-Zealand-based Sand Waves and Turbulence") research programme was carried out to advance understanding of subaqueous sand waves. The programme was based around detailed measurements at varying scales of bed morphologies and associated flow fields as sand waves formed from plane-bed conditions and grew to equilibrium. This paper outlines the philosophy and details of the SWAT.nz programme, with the aim of providing insight into experiment and analysis design and methodologies for studies of highly-variable bed surfaces and flows. Example challenges addressed in the SWAT.nz programme include the measurement over large spatial domains of developing flow fields and three-dimensional bed morphology, including flow measurements below roughness (sand-wave) crests, and how to interpret the collected measurements. Insights into sand-wave dynamics that have arisen from the programme are presented to illustrate the values of the SWAT.nz programme and the developed methodologies. Results are presented in terms of mobile-bed processes, and flow-bed interaction and flow processes for fixed-bed roughness and erodible beds, respectively.

7

Double-averaged velocity profiles over fixed dune shapes

McLean S. R., Nikora V. I., Coleman S. E.

Acta Geophysica

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2008

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Vol. 56, no. 3

669-697

EN

Spatially averaged profiles of time averaged velocity, using integrals over thin horizontal slabs (Cartesian double average), are employed in characterizing the flow over fixed dune shapes. For comparison the spatial averaging method of Smith and McLean (1977) that averages along lines at constant distance from the local bed elevation is also investigated. The Cartesian double averaged profiles of the inverse of the velocity shear are nearly constant below the crest elevation, but increase rapidly above the crest level. This results in velocity profiles that increase linearly with distance from the bed below the crest. Above the crest it can be argued that the velocity increases logarithmically, but a power law profile can also be argued. Spatially averaged eddy viscosity profiles are calculated by multiplying the average Reynolds stress by the inverse shear. The resulting profile is more complex than the uniform flow counterpart.

8

Wyniki badań geologicznych i archeologicznych na stanowisku Huta Radoryska 1 (Polska południowo-wschodnia)

Żarski M., Przeździecki M., Przasnyska J.

Przegląd Geologiczny

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2006

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Vol. 54, nr 3

238-244

EN

The flint material found in 2001 on the dune surface at Huta Radoryska in South-Podlasian Lowland near Żelechów is associated with human activity. The dune is located at Mała Bystrzyca depression. This depression, filled with the Wartanian silts, Eemian, Vistulian sands and Holocene peats, was formed after dead ice had thawed during deglaciation of the Wartanian ice sheet. The dune is built from eolian sands, mainly accumulated in the Late Vistulian (the Younger Dryas). The palaeosol (podsolic), formed in the Atlantic Period, occurs in the upper part of the dune. There were flints (344) pieces within humus horizon A1 of this palaeosol and above it. Flint cores and tools were recognised among flints. Most of the artefacts were connected with the Mesolithic (the Komornica and Chojnice-Pieńki Culture). Few Late Palaeolithic and Bronze Age flint artefacts were also found. Human activity have lasted for over 10 thousand years on this dune.

9

The results of integrated investigations of the Lithuanian coast of the Baltic Sea : geology, geomorphology, dynamics and human impact

Bitinas A., Žaromskis R., Gulbinskas S., Damušyte A., Žilinskas G., Jarmalavičius D.

Geological Quarterly

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2005

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Vol. 49, No. 4

355--362

EN

Integrated investigations of the Lithuanian coast of the Baltic Sea were carried out in 1999-2004 in order to satisfy an increased demand for information about the shoreline. The area of investigations included the beach and the protective dune or cliff (i.e. an onshore belt 100-300 mwide) and reached 15-20 misobaths in the offshore region. This study has resulted in the Geological Atlas of the Lithuanian coast of the Baltic Sea, which consists of digital maps including a geological-geomorphological map, a map of anthropogenic load at a scale of 1:5000 and an explanatory note. Data arrays from shoreline geodynamic monitoring and from field and analytical studies as well as descriptions of borehole sections are provided in graphic and textual annexes. On basis of these investigations 92 morpholithological profiles of the offshore zone and 101 geological cross-sections of the onshore zone were prepared. The basic geological information in the form of maps and special data arrays allows assessment of the current geological condition of the Baltic Sea shores and enables forecasts for their development. It also can be used for environmental protection and land use in the shoreline area: prevention of erosion, designing of protected, recreation and urban areas, as well as substantiation and development of a seashore monitoring system.

10

Dating of the dune in Kępa Kujawska

Oczkowski H. L., Przegiętka K. R., Lankauf K. R., Szmańda J.

Geochronometria

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2000

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Vol. 18

63-68

EN

A dune in Kępa Kujawska is located on the edge of the Toruń Basin. Preliminary studies on the natural thermoluminescence (TL) revealed relative chronology of the dune. The TL profile exposed three stages of the dune formation, which are correlated with three eolian members of dune deposits indicated by sedimentological investigations. The experiments on optical bleaching show that light (sunlight as well as laboratory light) only partially resets natural TL in that material. The high level of residual TL was taken into account in absolute dating of the dune. The TL ages obtained for quartz sand from the upper member are confirmed by radiocarbon dating of soil and burn horizon in proximal part of hte dune. Archaeological remains found in the dune give another evidence for truthfulness of TL dating results. The TL age of the middle member is consistent with conclusions from pollen analysis in the dune and its environments. The formation of this dune was started in the Late Glacial, probably in the Younger Dryas. In this period eolian deposition was stimulated by variable climate conditions. The upper member of the dune is connected with Neolithic and Iron Cultures when anthropogenic activity initiated eolian processes again. During the Atlantic and the Subatlantic periods the dune was rebuilt.