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Number of results: 8
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Abstract

Phytoplankton samples were collected at 62 stations in the European Arctic Seas and the Faroe — Shetland Islands area. Over 30 species of dinoflagellates were found. 22 species are illustrated by original drawings. The data on synonyms, size or size variability on the distribution and environmental factors (temperature and salinity) are given.
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Abstract

Phytoplankton samples were collected at 74 stations in the European Arctic seas, 28 species of the armoured din oft age Hates being found. Thirteen dinoflagellates are illustrated by original drawings. The data on synonyms, size or size variation, localities and environmental factors (temperature and salinity) at the surface are given.
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Abstract

It is assumed that close to the margins of ice-sheets, glacial, fluvial and aeolian processes overlap, and combined with weathering processes, produce numerous sediments, in which quartz is a common mineral. Quartz grains, if available, may serve as a powerful tool in determining the depositional history, transportation mode and postdepositional processes. However, quartz grain studies in some modern glacial areas are still sparse. In this study, we examine for the first time quartz grains sampled from the modern glacial and proglacial environments of the Russell Glacier, southwest Greenland in binocular microscope and scanning electron microscope, to analyze their shape, character of surface and microtextures. We debate whether the investigated quartz grains reveal glacial characteristics and to what extent they carry a signal of another transportation and sedimentary processes. Although glacial fracturing and abrasion occur in grain suites, most mechanical origin features are not of a high frequency or freshness, potentially suggesting a reduced shear stress in the glacier from its limited thickness and influence of the pressurized water at the ice-bed. In contrast, the signal that originates from the fluvial environment is much stronger derived by numerous aqueous-induced features present on quartz grain surfaces. Aeolian-induced microtextures on grain surfaces increase among the samples the closest to the ice margin, which may be due to enhanced aeolian activity, but are practically absent in sediments taken from the small scale aeolian landforms. In contrast, aeolian grains have been found in the bigger-size (1.0-2.0 mm) investigated fraction. These grains gained the strongest aeolian abrasion, possibly due to changes in transportation mode.
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Abstract

We test the application of dendrochronological methods for dating and assessing the environmental impacts of tsunamis in polar regions, using an example of the 21 November 2000 landslide−generated tsunami in Vaigat Strait (Sullorsuaq Strait), West Greenland. The studied tsunami inundated a c . 130 m−wide coastal plain with seawater, caused erosion of beaches and top soil and covered the area with an up to 35 cm−thick layer of tsunami deposits composed of sand and gravel. Samples of living shrub, Salix glauca (greyleaf willow) were collected in 2012 from tsunami−flooded and non−flooded sites. The tree−ring analyses reveal unambiguously that the tsunami−impacted area was immediately colonized during the following summer by rapidly growing shrubs, whilst one of our control site specimens records evidence for damage that dates to the time of the tsunami. This demonstrates the potential for dendrochronological methods to act as a precise tool for the dating of Arctic paleotsunamis, as well as rapid post−tsunami ecosystem recovery. The reference site shrubs were likely damaged by solifluction in the autumn 2000 AD that was triggered by high seasonal rainfall, which was itself a probable contributory factor to the tsunami−generating landslide.
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Abstract

Phytoplankton samples were collected at 141 stations in the Norwegian, Greenland, Barents and Baltic seas, in July-August 1992 and July-August 1993. In fifteen of these stations 22 unarmoured dinoflagellate species from the order Gymnodiniales belonging to the genera Amphidinium, Cochlodinium, Gymnodinium, Gyrodinium, Torodinium and Polykrikos have been found. Data on 16 species are given here, including synonyms, size or size variation, localities and environmental factors (temperature and salinity at the surface). 14 species are illustrated.
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Abstract

Shallow−marine deposits of the Krabbedalen Formation (Kap Dalton Group) from Kap Brewster, central East Greenland, yielded rich dinoflagellate cyst and pollen− −spore assemblages. Previously, this formation yielded also rich mollusc and foraminifer age−diagnostic assemblages. A Lower Oligocene age of the Krabbedalen Formation seems to be supported by the dinoflagellate cyst assemblage analysis, while the pollen−spore as− semblages point to a wider stratigraphic age range within Oligocene–Middle Miocene.
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Abstract

Based on the results of CTD measurements (in situ) made during r/v „Oceania" cruises in the Norwegian and Greenland Seas in 1986—1988 selected aspects of termohaline structure and water dynamics of chosen regions of the seas were described. Examples of space-time variations of temperature and salinity fields were presented and water masses geostrophic transport on the limits of the Norwegian Sea (upon the Atlantic Ocean and the Barents Sea) was estimated.
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Abstract

The Fleming Fjord Formation (Jameson Land, East Greenland) documents a diverse assemblage of terrestrial vertebrates of Late Triassic age. Expeditions from the turn of the 21st century have discovered many important fossils that form the basis of our current knowledge of Late Triassic Greenlandic faunas. However, due to the scarcity and incompleteness of the fossils and their insufficient study, our understanding of the taxonomic diversity of the Fleming Fjord Formation is hindered. Here, we report the preliminary findings of a Polish−Danish expedition to the Fleming Fjord Formation that took place in 2014. Three areas were visited – the fairly well known MacKnight Bjerg and Wood Bjerg and the virtually unexplored Liasryggen. MacKnigth Bjerg and Liasryggen yielded fossils which promise to significantly broaden our knowledge of vertebrate evolution in the Late Triassic. Stem−mammal remains were discovered at Liasryggen. Other fossils found at both sites include remains of actinopterygians, sarcopterygians, temnospondyl amphibians and various archosaurs (including early dinosaurs). Numerous vertebrate trace fossils, including coprolites, pseudosuchian footprints, theropod and sauropodomorph dinosaur tracks, were also discovered. Newly discovered skeletal remains as well as abundant trace fossils indicate higher tetrapod diversity in the Late Triassic of Greenland than previously thought. Trace fossils also allow inferences of early theropod and sauropodomorph dinosaur behaviour.
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