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Rozwój wybrzeża Zatoki Gdańskiej w rejonie ujścia Wisły Martwej

100%

Jegliński W.

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tom Vol. 61, nr 10

587--595

EN

Vistula River is the second largest river in the Baltic Sea catchment area. Its delta is located at the Gulf of Gdańsk region and has been formed during the last ca. 13500 yr. The Dead Vistula is the oldest historically documented, and also the westernmost channel of the delta, drained water directly into the sea. The aim of the study was to reconstruct the development of the Dead Vistula outlet area during the late Holocene. At the end of the Atlantic period marine transgression reached the farthest range on the investigated area. During the next ca. 3000 yr. the embayment was filled by marine sand. The preserved dune ridges indicate earlier shoreline position. The oldest of them stabilized, acc. to OSL dating, between 3950 and 3150 yr. BP and are oriented WSW-ENE. The orientation of the dune ridges lying further to the north, changes gradually to WNW-ESE. The next generation of dunes stabilized between 2760-2380yr. BP. Vistula outlet in this place was created between 3000-2500 yr. and in that time the process of outlet cone forming was started. Orientation of the younger dune ridges, stabilized between 2220 and 1505 yr. BP, are in close connection with the development of the area. The process had not been steady in time. Two periods of accretion was sepa¬rated by stagnation time. The total amount of the material accumulated during both stages of development was ca. 178 mln. m3. The numerous ofpreserved historical bathymetric plans were very helpful for reconstruction ofthe outlet cone development during the second stage. The extension of the cone ended in the year 1840, when the new mouth has been formed. Since that time, as a result of the lack of clastic material supplying the cone earlier, marine erosion increases.

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Baza danych fauny z osadów neogenu południowego Bałtyku

51%

Krzymińska J. , Jegliński W. , Przezdziecki P.

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tom Vol. 54, nr 3

228-230

EN

The project aimed at creating a digital archive of species documented from the Quarternary deposits of the Southern Baltic Sea. The records are ordered and supplemented with diagnostic descriptions. Users interested in micro- and malacofauna can use the data in various applications (e.g., GIS). Besides, the database is also compatible with zoological specimen collections for museums, using a standard catalogue registry. The database was created in MS Visual FoxPro format. Access to the database (including browsing, searching and sorting options) is possible via a custom- made user interface application. The database is distributed on CD-ROM including also the necessary software. Because of its "open" character, the database will be systematically updated with new results of research on the Southern Baltic. The new faunistic database is designed as compatible with an already existing geological data base (Neptun) in the Marine Geology Branch of the Polish Geological Institute. Such cooperation will allow users to get additional information (lithology, petrography, etc.) concerning the studied samples of the Quaternary faunal remains.

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Recent development of the Vistula River outlet

38%

Graniczny M. , Janicki T. , Kowalski Z. , Koszka-Maroń D. , Jegliński W. , Uścinowicz S. , Zachowicz J.

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tom Vol. 11

103--107

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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Baltic Sea coastal erosion; a case study from the Jastrzębia Góra region

38%

Uścinowicz G. , Kramarska R. , Kaulbarsz D. , Jurys L. , Frydel J. , Przezdziecki P. , Jegliński W.

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tom Vol. 20, No. 4

259--268

EN

The coastline in the Jastrzębia Góra area can be divided into three major zones of general importance: a beach and barrier section, a cliff section, and a section protected by a heavy hydrotechnical construction. These areas are characterised by a diverse geology and origin, and hence different vulnerability to erosion. In addition, observations have demonstrated a different pace of erosion within each zone. Based on the results obtained by remote sensing methods (analysis of aerial photographs and maps), it has been determined that the coastline in the barrier area, i.e., to the west of Jastrzębia Góra, moved landwards by about 130 m, in a period of 100 years, and 80 m over about 50 years. A smaller displacement of the shoreline could be observed within the cliff. Between the middle of the twentieth and the start of the twenty-first centuries the shore retreated by about 25 m. However, in recent years, an active landslide has led to the displacement of the uppermost part of the cliff locally up to 25 m. Another issue is, functioning since 2000, a heavy hydrotechnical construction which has been built in order to protect the most active part of the cliff. The construction is not stable and its western part, over a distance of 50 m, has moved almost 2 m vertically downwards and c. 2.5 m horizontally towards the sea in the past two years. This illustrates that the erosional factor does not comprise only marine abrasion, but also involves land-based processes determined by geology and hydrogeology. Changes in the shoreline at the beach and barrier part are constantly conditioned by rising sea levels, the slightly sloping profile of the sea floor and low elevation values of the backshore and dune areas. Cliffs are destroyed by mass wasting and repetitive storm surges that are responsible for the removal of the colluvium which protects the coast from adverse wave effects. Presumably, mass movements combined with groundwater outflow from the cliff, plus sea abrasion cause destabilisation of the cliff protection construction.

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Impact of sand extraction from the bottom of the southern Baltic Sea on the relief and sediments of the seabed

32%

Uścinowicz S. , Jegliński W. , Miotk-Szpiganowicz G. , Nowak J. , Pączek U. , Przezdziecki P. , Szefler K. , Poręba G.

Oceanologia

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2014

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tom No. 56 (4)

857--880

EN

Investigations of the geological structure and seabed dynamics as well as the morphological and sedimentological effects of sand extraction generated by different mining techniques were carried out in Polish waters of the Baltic Sea, NW of the Gulf of Gdańsk, at a water depth of 15-17 m. Three research cruises took place: just before, directly after and 11 months after dredging operations. Seismoacoustic profiling, a multibeam echosounder, a side-scan sonar, a 3 m vibro-corer and a box-corer were used during the research cruises. The grain size distribution and 137Cs content of the sand samples were determined. Marine shells were dated by the AMS14C technique and pollen analyses were carried out on samples of muddy sands lying below the marine sand. A 2 to 4.5 m thick layer of marine sands lies on the boulder till and locally on late Pleistocene ice margin lake deposits. The 137Cs content indicates that the 0.4-0.8 m thick sand layer is mobile during storms. After the dredging operations, four pits with diameters from 80 to 120 m, depths from 3 to 4.5 m and slopes with gradients up to 30-55° were measured. Several smaller irregularly shaped pits and double furrows 30-150 m in length and 0.3-0.5 m in depth were found. The sonar mosaic also shows a 50-100 m buffer zone of fine sand around the pits which flowed over the dredger's side with water and settled on the bottom. During one year after the dredging operation the furrows generated by trailer suction hopper dredging as well as the fine sand cover around the pits disappeared completely. The four post-dredging pits left by stationary suction dredging were shallower by 2-2.5 m, their diameters increased by 40-50 m, the gradient of the slopes was reduced by up to 5-10°, and the total volume was only about 3.5% smaller than directly after dredging.

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Czwartorzęd Zatoki Pomorskiej i perspektywy surowcowe

32%

Kramarska R. , Jegliński W. , Kaulbarsz D. , Pączek U. , Przezdziecki P. , Bojakowska I. , Koszka-Maroń D. , Relisko-Rybak J. , Uścinowicz S.

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tom Vol. 64, nr 8

552--563

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.