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EN
Climate fluctuations and related crucial environmental changes in the Late Glacial and Holocene in the southern Baltic Sea area can be reconstructed by mollusc analyses. Lacustrine sediments host an association of molluscs and other fossils, including freshwater species such as: Armiger crista f. cristatus, Gyraulus laevis, Lymnaea peregra, Pisidium casertanum, Pisidium casertanum f. ponderosa, Pisidium milium, Pisidium nitidum, Pisidium obtusale f. lapponicum, Valvata cristata and Pisidium conventus, which indicate cold climate. Deposition in freshwater reservoirs continued during the Early Holocene. at that time, species characteristic of cold freshwater environments were accompanied by freshwater mollusc species that require higher temperatures: Bithynia tentaculata, Physa fontinalis and Pisidium amnicum. This suggests climate warming in the Preboreal period. These lacustrine sediments were partly destroyed and covered by marine sands during the Middle and Late Holocene. Good indicators of changing environmental conditions from freshwater to marine are the following marine species found in the sediments: Hydrobia ulvae, Hydrobia ventrosa, Cerastoderma glaucum, Mytilus edulis and Macoma balthica.
PL
Zmiany klimatyczne, a za tym daleko idące zmiany środowiska w późnym glacjale i holocenie na obszarze południowego Bałtyku mogą być wyjaśniane także przez badania fauny mięczaków. Na obszarze południowego Bałtyku w okresie późnego glacjału występowały gatunki słodkowodne wskazujące na klimat zimny, takie jak: Armiger crista f. cristatus, Gyraulus laevis, Lymnaea peregra, Pisidium casertanum, Pisidium casertanum f. ponderosa, Pisidium milium, Pisidium nitidum, Pisidium obtusale f. lapponicum, Valvata cristata, Pisidium conventus. Akumulacja jeziorna w słodkowodnych zbiornikach strefy przybrzeżnej kontynuowała się w okresie wczesnego holocenu. W tym czasie oprócz gatunków słodkowodnych, zimnolubnych pojawiły się gatunki mięczaków i małżoraczków słodkowodnych, o wyższych wymogach termicznych (Bithynia tentaculata, Physa fontinalis, Pisidium amnicum). Świadczy to o ociepleniu się klimatu w okresie preborealnym. Zrastanie przybrzeżnych zbiorników rozpoczęło się w okresie borealnym i trwało również w okresie atlantyckim. W tym czasie miały miejsce wlewy wód morskich do zbiorników. Wskaźnikiem tego jest liczne występowanie morskich gatunków takich jak: Hydrobia ulvae, Hydrobia ventrosa, Cerastoderma glaucum, Mytilus edulis, Macoma balthica. W osadach piaszczystych w okresie subborealnym i subatlantyckim zdecydowanie przeważała fauna morska.
EN
The study was carried out in the wall of a cliff that formed as a result of erosional cutting in the western foreland of a moraine landform from the Pomeranian and Gardno phases (Upper Plenivistulian, Rowy-Ustka clifs; northern Poland). Individual lithostratigraphic units have been documented: glaciofluvial delta deposlts, Poddąbie Till, lacustrine-glacial Wytowno Formation (consisting of three facies: deltaic, lower diamicton, and upper diamicton), lacustrine deposits of the Orzechowo Formation with a thick peat layer, and aeolian series at the cliff crest. The Wytowno Formation deposits include the following lithologies: medium-grained sands, fine-grained sands, muddy sands, muds, silty clays, clays, varved clays, fine-grained multi-fraction deposits, and tills (Dębina Till). Very high inclination of the strata is the result of glaciodynamic deformation. The deposits were accumulated in a proglacial lake. They are characterized by mud and clay as well as sand and sand-muddy lithofacies. The vastness of the water body is evidenced by a considerable size of the delta, and by massive structures of the clay layers.
PL
W artykule przedstawiono próbę ilościowej i jakościowej oceny morfodynamiki fragmentu wysokiego wybrzeża zlokalizowanego na wschód od portu w Ustce. W tym celu przeanalizowano zmienność przebiegu górnej krawędzi klifu w Orzechowie w różnych skalach czasowych. Wielkość erozji określano na podstawie map archiwalnych oraz przeprowadzonych w terenie serii pomiarowych LiDAR z wykorzystaniem naziemnego skaningu laserowego. W oparciu o wielkość erozji wyznaczano uśrednione tempo erozji klifu [m a–1] dla każdego umownego profilu prostopadłego do brzegu. Zaprezentowana metoda umożliwia porównanie tempa postępującej erozji klifów wybrzeży Bałtyku w sposób jednolity, niezależnie od budowy geologicznej, wysokości czy ekspozycji zboczy.
EN
The aim of this paper was quantitative and qualitative investigation of morphodynamics of high coast located to the east of the Ustka harbour. Therefore, the course variability of top margins of the Orzechowo Cliff became analysed at different time scales. The magnitude of erosion was obtained from archival maps and/or LiDAR field measurements using terrestrial laser scanner. Based on the magnitude of erosion, the average recession rate of the cliff [m a–1] was determined for every hypothetical profile perpendicular to the shore. The presented approach provides the possibility to compare the recession rates of cliffs of the Baltic coast in a uniform manner, regardless of geological structure, elevation, or slope exposure.
EN
The study area (20 km2) covers part of the Vistula River's delta front and prodelta, active since 1895. The Vistula river-mouth fan is a unique area of intense accumulation of clastic material, whose development can be investigated from a precisely defined moment in the history of its origin to the present day. The research has resulted in a morphodynamic model (based on bathymetric plans of the contemporary Vistula mouth area over the period of 1894–2000) and a facies model of the Vistula mouth fan. The analysis of the morphometric models shows that 105 years after the Vistula Cross-Cut was opened, the volume of the sediment accumulated in the fan was 133.39 million m3 and the rate of accretion has decreased. Facial models were created on the basis of results of lithological analysis of sediments. The Vistula mouth fan is built of delta front sediments represented mainly by sand facies (fine-, medium- and coarse-grained, locally with gravel, as well as marine and freshwater mollusc shells), only locally by silt facies. The thickness of the river-mouth fan sands is 11–15 m. The prodelta sediments are found on the fan's forefield within a depth zone of 12–16 m, and they also underlie the fan sediment. Their thickness is up to ca. 10 m. Cluster analysis of the individual grain-size distributions made it possible to distinguish two lithofacies in the Vistula mouth fan: lithofacies A (fine-grained sand, silty sands, clayey silt) and lithofacies B (medium-grained and coarse-grained sand). This allowed reconstructing the processes which has taken place over the last 100 years, and to forecast future changes in the development of the active part of the Vistula Delta.
5
EN
This paper summarizes four years of geological research in the Pomerania Bay and Oder Bank. As a result of the synthesis of new and archival data,we have compiled maps, cross-sections and models depicting the geological structure of the Quaternary and its basement, and the relief of structural surfaces. Two main seismostratigraphic sedimentary complexes are distinguished. The first corresponds to Pleistocene glacial and interstadial deposits. The second one is composed of Late Glacial and Holocene lacustrine-swamp and marine sediments. The outline of geochemical condition of the sea bottom is also presented. The content of the elements is always below the acceptable concentration and the origin of the elements is geogenic. Special attention has been given to mineral resources on the bottom surface and to documenting deposits of sand containing heavy minerals. The characterization of areas with sands suitable for beach nourishment and valorization of deposits and prospective areas have also been of great importance. The history of the development of the geological structure and palaeogeography of the area is the summary of the results.
EN
The western cliff coast of Puck Lagoon has a lentgh of 7900 m. Its development proceeds as a result of processes of desintegration, denudation and marine erosion. The mass movement getting on depends on kind of sediment, geometry of slope and plant cover. Earth fall and talus accumulation prevail. As an effect of this processes, the cliff retreats in the form of small wastes.
7
Content available Recent development of the Vistula River outlet
EN
The Vistula River mouth is an unique example of river’s outlet observed since the birth in 1895 to present day. There is a large documentation of morphological changes in the outlet area. In 1895, a 7 kilometres canal was dug into which the waters of the Vistula were let in. Since 1895, most of the water discharge and all sediment transport reach the Gulf through artificial channel c. 20 km east of Gdańsk. During the last 100 years, the shoreline has been shifted seaward c. 1.5 km on the eastern side, to c 2.5 km on the western side of the Vistula mouth. Isobath of 5 m moved seaward c. 3 km and isobaths of 10 and 15 m shifted 2.5 km. During the years 1895-1997, land area accreted to 3,019,000 m2. The volume of the river-outlet cone in the year 2000 was 133.39 mln m3 and the average rate of sediment growth over the 105 years was c. 1.27 mln m3 per year.
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