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Abstrakt

Studies of Quaternary sediments of South Spitsbergen (Hornsund, Bellsund and northern Billefjorden regions) focus on their occurrence, origin and chronostratigraphy. Methods and results of geological mapping are described. Glacial, glaciofluvial, glaciolacustrine and aeolian sedimentary environments, rock glaciers, taluses and raised marine beaches are presented. Mutual relations of these sediments as well as their radiocarbon and thermoluminescence datings made chronostratigraphy of Late Quaternary glacial episodes possible. Results of preliminary neotectonic studies are also presented, the same as works on periglacial phenomena, chemical weathering and tundra vegetation. Key significance of the studies for the Quaternary evolution of the Arctic and for better recognition of geodynamic phenomena of Pleistocene glaciations in Poland (Tatra and Sudeten Mts included) is underlined.
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Abstrakt

Attempt of correlation of raised marine beaches and glacial episodes in West Spitsbergen is presented for the Middle and the Late Quaternary. A model of predominating Barents Sea shelf ice sheet during the Saalian and of co-existing distinct local ice domes during the Vistulian is postulated on the basis of varying land uplift. Glacial episodes in Spitsbergen are referred to the ones in continental Europe and North America. Rough prognosis of climatic trends is introduced.
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Abstrakt

Studies of the Quaternary evolution of the Hornsund Region in Spitsbergen focused in nine key areas, in which detailed fieldworks with mapping and sampling to radiocarbon and thermoluminescence analyses have been done. Glacial history of the Hornsund Region is known from the Torellkjegla (Holsteinian) Interglacial up to the recent times. The Wedel Jarlsberg Land (Saalian) Glaciation was the most widespread in this part of Spitsbergen and consisted of two stades(?). It was followed by considerable glacier retreat during the Bogstranda (Eemian) Interglacial, the latter being represented by development of soils. Four glacier advances (the two younger ones are the Lisbetdalen and the Slaklidalen stages) occurred during the Sörkapp Land (Vistulian) Glaciation. Three glacier advances (Gronfjorden and Revdalen stages, followed by the Little Ice Age) were recognized for the Holocene. The oldest and highest (although somewhat questionable) raised marine beaches come presumably from the Wedel Jarlsberg Land Glaciation. The beaches 80-100 m a.s.l. were formed during the Bogstranda (Eemian) Interglacial. The beaches 20-60 m a.s.l. are correlated with the Sórkapp Land Glaciation. All the lower marine beaches were formed during the Holocene.
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Abstrakt

Field mapping and analysis of air photos enabled to prepare a photogeological map of Treskelen-Hyrnefjellet-Kruseryggen area in scale of 1:10,000. Slope, glacial and nival landforms and sediments, and ten raised marine beaches were distinguished. Morphogenetic evolution of the area is also presented, with discussion of probable glacier advances and land uplift during the Late Pleistocene and the Holocene.
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Abstrakt

Mapping and analysis of air photos enabled preparation of a photogeological map of the Hansbreen-Sofiekammen region in a scale of 1 : 10,000. Glacial, slope and marine landforms and sediments were distinguished. Supplied with thermoluminescence and radiocarbon data, a morphogenetic evolution of the area could be presented. Four Pleistocene and Holocene glacier advances were distinguished. Seven raised marine beaches result from the Pleistocene and the Holocene uplift of the land.
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Abstrakt

Basing of fieldworks geomorphologic and geologic setting of 14 raised marine beaches in northern Hornsund Region was presented. Their age is approximated by radiocarbon and thermoluminescence datings of sediments. The latter indicated that the four highest but mostly questionable marine beaches (220—230,200—205,180—190 and 100—120 m a.s.l.) should be referred to the Wedel Jarlsberg Land (Saalian) Glaciation. The four lower beaches (80—95, 70—75, 50—60 and 40—46 m a.s.1.) are connected with the Bogstranda (Eemian) Interglacial and the pre-maximum part of the Sorkapp Land (Vistulian) Glaciation. The post-maximum part of this glaciation, including Lisbetdalen Stage (50—40 ka) and Slaklidalen Stage (30—20 ka), was the time when the three still lower marine beaches (32—35, 22—25,16—18 m a.s.l.) were formed. Three lowermost marine beaches (8—12,4.5—6,2 m a.s.l.) are of the Holocene age.
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Abstrakt

We propose contents of topographic maps for polar areas to be supplemented with such landforms that are easily identified during the analysis of air or terrestial photographs. Such landforms include rock outliers (monadnocks), glacial boundaries, a beach and thick mantles of tundra vegetation. All these landforms create together with fluvial and lake patterns a system of elements that enable location of users and therefore make preparation of other (e.g. geological, geomorphological or glaciological) maps possible.
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Abstrakt

Thermoluminescence datings of glacial and marine sediments from Sörkapp Land, southern Spitsbergen enabled to limit the Late and Middle Pleistocene glacial events in this area. Sediments of raised beaches at 15—18, 30—38 and 42—56 m a.s.l. in Breinesflya were TL dated for 63, 68 and 87 ka respectively. Four other dates from Lisbetdalen, Slaklidalen and Sergeijevskardet proved two glacial advances during the Sörkapp Land ( = Wiirm) Glaciation. named the Lisbetdalen Stage (47 and 41 ka) and the Slaklidalen Stage (28 and 22 ka). Glacial sediments on slopes of Gavrilovfjellet and Strupryggen were dated for 141 and 217 ka respectively. These dates prove the glaciers of the Wedel Jarlsberg Land (= Riss) Glaciation occupied a considerably larger area in southern Spitsbergen than the glaciers of the following Sorkapp Land Glaciation.
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Abstrakt

This article presents characteristics of the Quaternary deposits and landforms of Ebbadalen, the Nordenskióldbreen foreląnd and the Wordiekammen massif on the basis of geomorphological mapping of this area and a number of geologic profiles A—L studied in detail. Glaciers were much more expanded during the Pleistocene than they are nowadays. Over a period referred to by the present authors as the Petuniabukta-Adolfbukta Stage they occupied the whole Ebbadalen area and the eastern part of Adolfbukta. Marine terraces of 70- 80, 60—65 and 50—55 m a.s.l. were formed earlier. At the turn of the Pleistocene three marine terraces were produced at 40—45, 30—35 and 20—25 m a.s.l. Throughout the Early Holocene transgression (the Ebbadalen Stage = the Thomsondalen Stage) glaciers occurred in nearly the entire Ebbadalen area and occupied a larger part of Adolfbukta than nowadays. During the Middle and Late Holocene marine terraces of 12—15, 5—8, 3—4 and 1—2 m a.s.l. were initiated. Two more glacier advances, the later relating to the Little Ice Age, took place during the Late Holocene
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Abstrakt

A sediment core, 350 cm long recovered from Młynek Lake, northern of Poland (Warmia and Masuria Region) was analyzed with respect to their content of diatoms and chrysophyte cysts. The aim was to reconstruct the lake water level and climatic changes during the past 2500 years. The recognized diatom assemblages displayed marked floristic changes along the sediment core samples. The main change in diatom composition consists of a shift from an assemblage dominated by benthic Fragilaria sensu lato species through marked intervals to a planktonic one in distinct zones. A high proportion of benthic to plankton taxa has been reported as indicative for a lowering of the lake level with long ice cover in a cold dry climate and a shift from benthic to planktonic diatom taxa reflects arising water level with longest growing season and reduced ice cover on the lake during a warm wet climate. Multivariate statistical analysis included hierarchical ascending clustering distinguished four diatom ecological groups. The analyzed core section was divided into 11 diatom zones according to a distribution of ecological groups and variation in abundance of dominant species supported by 14C data. The results displayed a developmental history of the Młynek Lake that can be divided into 6 main phases of alternating warm wet and cold dry shifts. A distinct dominance of planktonic eutrophic indicator diatoms accompanied by a low abundance of chrysophyte cysts indicates increased lake trophicity and a general trend for the increasing anthropogenic impact.
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