Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "zlodowacenie" wg kryterium: Temat


Wyświetlanie 1-11 z 11
Tytuł:
Signatures of Late Neoproterozoic Gondwana assembly and Maronian glaciation in Lesser Himalaya: a palaeogeographical and stratigraphical approach
Autorzy:
Umar, M.
Betts, P.
Khan, M. M. S.
Sabir, M. A.
Farooq, M.
Zeb, A.
Jadoon, U. K.
Ali, S.
Powiązania:
https://bibliotekanauki.pl/articles/139442.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Neoproterozoic
palaeogeography
Glaciation
Rodinia break-up
Lesser Himalaya
neoproterozoik
paleogeografia
zlodowacenie
Rodinia
rozpad
Himalaje Małe
Opis:
Stratigraphical and sedimentological analyses of Late Neoproterozoic successions in Lesser Himalaya are combined herein with palaeogeographical considerations and comparisons with equivalent successions in India and South China. The succession starts with the Hazara Formation, which contains complete and incomplete Bouma sequences suggesting its deposition in deep marine turbidite settings. The overlying Tanawal Formation, rich in massive sandstone, shale and siltstone, was deposited in shallow marine conditions, as indicated by the presence of parallel lamination, large scale tabular, trough cross- and hummocky cross-stratifications. The Tanawal Formation facies shift laterally from proximal (south-southeast) to distal (north-northwest). The glaciogenic Tanaki Boulder Bed, overlying the Tanawal Formation, was deposited during the Maronian glaciation. It is equivalent to the Blaini Formation of India, and to the Sinian diamictites of South China. The Abbottabad Formation of Cambrian age overlies the Tanaki Boulder Bed, and is composed of dolomite, chert nodules and phosphate-rich packages; similar successions are documented in India and South China at the same stratigraphical interval. The similarities of the Neoproterozoic successions of Lesser Himalaya (both in Pakistan and India) and South China suggests their possible proximity during the break-up of Rodinia and the assembly of the Gondwana Supercontinent.
Źródło:
Acta Geologica Polonica; 2015, 65, 1; 1-19
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reconstruction of sediment provenance and transport processes from the surface textures of quartz grains from Late Pleistocene sandurs and an ice-marginal valley in NW Poland
Autorzy:
Woronko, B.
Pisarska-Jamroży, M.
van Loon, A. J.
Powiązania:
https://bibliotekanauki.pl/articles/94315.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
quartz grain micromorphology
ice-marginal valley
sandur
Weichselian glaciation
Polska
mikromorfologia ziaren kwarcu
pradolina
zlodowacenie północnopolskie
Polska
Opis:
During the Pomeranian phase of the Weichselian glaciation (~17–16 ka), the Toruń-Eberswalde ice-marginal valley (NW Poland and easternmost Germany) drained water from the Pomeranian ice sheet, while intensive aeolian processes took place across Europe in the foreland of the Scandinavian ice sheet (‘European Sand Belt’). The micromorphology of the quartz grains in the Toruń-Eberswalde ice-marginal valley shows no traces of these aeolian processes, or only vague signs of aeolian abrasion. This is unique among the aeolian sediments in other Pleistocene ice-marginal valleys in this part of Europe. The study of the surfaces of the quartz grains shows that the supply of grains by streams from the south was minimal, which must be ascribed to the climate deterioration during the Last Glacial Maximum, which resulted in a decrease of the discharge of these extraglacial rivers to the ice-marginal valley.
Źródło:
Geologos; 2015, 21, 2; 105-115
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Glacial Terminations II and I as recorded in NE Iceland
Autorzy:
Vliet-Lanoë, Brigitte
Guðmundsson, Agust
Guillou, Hervé
Guégan, Soléne
Loon, A. J. (Tom)
Vleeschouwer, François
Powiązania:
https://bibliotekanauki.pl/articles/94567.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
ice-stream patterns
palaeolake
deglaciation
Last Glacial Maximum
mid-Eemian cooling
Iceland
paleojezioro
deglacjacja
ostatnie zlodowacenie
Islandia
Opis:
Volcanism in eastern Iceland has controlled the changes in glacier- and river-drainage patterns and the sedimentary budget, particularly during the Middle and Late Pleistocene. The glacial extent in NE Iceland appears to be related to the impact of volcanic activity, not only on the ice-stream dynamics, but also on the sedimentary successions. Analysis of the Jökuldalur and Jökulsa á Brù records results in a new interpretation of the changes in ice extent and flow direction for at least the last two glaciations. From MIS 8 onward, the development of the Snæfell volcano apparently forced the ice stream that derived from the Vatnajökull ice cap to take another course; it also affected the offshore sedimentary budgets at the new outlet at Vopnafjördur. The MIS 6 ice sheet was thick and extensive, and associated with an ice-stream diversion to the North. The thick sedimentary complex of palaeolake Halslón was formed close to an outlet of the Vatnajökull, the Brùarjökull, during Termination II and a part of the MIS 5e interglacial. The deposits formed during MIS 5e record two climate optima interrupted by two successive glacial advances correlated with the mid-Eemian cooling. The deposits of the Weichselian deglaciation (Termination I) are much more limited in thickness. During the Last Glacial Maximum and the Late Glacial, glaciers also seem to have been restricted in the Jökulsa á Brù area. Valley glaciers issued from the Brùarjökull re-advanced several times in the Jökuldalur only during at least the Older Dryas, the Younger Dryas and the Preboreal. NE Iceland has undergone considerable deglaciation since the Bølling. In contrast to the conclusions of previous studies, the results presented here are consistent with data on the glaciations in other Nordic regions and can increase the understanding of the mid-Eemian cooling.
Źródło:
Geologos; 2010, 16, 4; 201-222
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lithological indicators of loess sedimentation of SW Poland
Autorzy:
Krawczyk, M.
Ryzner, K.
Skurzyński, J.
Jary, Z.
Powiązania:
https://bibliotekanauki.pl/articles/100800.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Śląski. Wydział Nauk o Ziemi
Tematy:
Dolny Śląsk
gleba
zmiana klimatu
zlodowacenie
Silesian Lowland
loess-soil sequence
grain-size indicator
climate change
last glaciation
Opis:
High-resolution grain-size investigations were carried out in two SW Polish loess sections: Biały Kościół (Niemcza-Strzelin Hills) and Zaprężyn (Trzebnica Hills). Each sequence was sampled by using the same methodology and samples were taken at 5 centimeters intervals. The particle size distribution was obtained with a Mastersizer 2000 laser, used for diffraction methods. From the obtained results the basic parameters and grain size indicators were calculated: Mz, Grain Size Index ratio, U-ratio and the percentage content of clay (< 4μm) and sand (> 63 μm). Both loess- soil sequences are composed of interfluve and slope loess facies and consist of five litho-pedostratigraphic units developed during the Late Pleistocene and Holocene: two loess units L1LL1, L1LL2 and three polygenetic fossil soils sets S0, S1 and L1SS1. The distance between these two profiles is about 60 km. Zaprężyn, as a section located more to the north, has almost no lower younger loess and higher level of weathering which could be related to proximity of this site to the Ice Sheet margin. The climate here was more extreme and harsh. What is more,the difference in development of soil L1SS1 can be observed: while in Biały Kościół pedogenesis process was slower and less disturbed than in Zaprężyn. The upper part of L1SS1 in Biały Kościół was deformed by gelifluction, frost heave and other periglacial processes. Mz indicator by the grain-size distribution in these sediments reflects subtle variations in the climatic system. Moreover, in Zaprężyn the content of sand fraction is higher than in Biały Kościół what can be the evidence of short episodes of strong winds during cold period of sedimentation. The aim of this paper is to compare two loess profiles by their stratigraphical and lithological similarities which are result of climate conditions and features of surrounding environment.
Źródło:
Contemporary Trends in Geoscience; 2017, 6, 2; 94-111
2299-8179
Pojawia się w:
Contemporary Trends in Geoscience
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Complex genesis of N-channel eskers illustrated with the example of an esker near Tosie (east-central Poland)
Złożoność genezy ozów powstałych w tunelach typu N na przykładzie ozu okolic Tosi (środkowo-wschodnia Polska)
Autorzy:
Frydrych, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/2095774.pdf
Data publikacji:
2021-12-30
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
Oz
tunel subglacjalny
rozpadlina lodowa
osady glacifluwialne
zlodowacenie warty
Polska
Esker
subglacial tunnel
open crevasse
glaciofluvial deposits
Saalian
Polska
Opis:
The study presents the problem of complex genesis of eskers formed in N-channels on the example of an esker located near Tosie in east-central Poland. The lithofacies analysis revealed a high diversity of structural and textural characteristics of sediments in this form. The esker consists of three sedimentation units. Coarse sediments of the esker core were deposited in the subenvironment of a subglacial tunnel, as an effect of bedforms migration under hydrostatic pressure. Opening of the tunnel resulted in the forming of an open crevasse, in which the cover of the esker core sediments was accumulated. These deposits recorded a significant variability of flow energy and sedimentation mechanisms, which indicates a strong influence of the ice-sheet ablation dynamics. During the final deglaciation stage, a part of the esker was covered with diamicton. Numerous soft-sediment deformation structures were identified within the esker. The sediments were dislocated vertically to the elevation of more than 8 metres. They constitute the record of buried dead-ice masses melting in the esker core sediments. Melting of the masses resulted in vertical displacement of sediments and formation of "the dead-ice structure". The complexity of esker genesis is characteristic of postglacial areas in Poland, where most eskers were formed in subglacial N-channels. Numerous research results confirm a considerably more frequent occurrence of the facies sequence of subglacial tunnel and open crevasse in eskers formed in N-channels than R-channels. This is indicated by a much greater dissimilarity of processes during different stages of esker formation on soft bed and solid substratum.
Badania ukazują problem złożoności genezy ozów powstających w tunelach typu N na przykładzie ozu okolic Tosi w środkowo- -wschodniej Polsce. Analiza litofacjalna wykazała duże zróżnicowanie strukturalnych i teksturalnych cech osadów tworzących formę. Oz zbudowany jest z trzech jednostek sedymentacyjnych. Gruboziarniste osady jądra ozowego powstawały w subśrodowisku tunelu subglacjalnego na skutek migracji form dna pod ciśnieniem hydrostatycznym. Otwarcie się tunelu spowodowało powstanie rozpadliny lodowej, w której następowała akumulacja jednostki pokrywającej osady jądra ozu. W osadach tych zapisała się znaczna zmienność energii przepływu oraz mechanizmów sedymentacji, co wskazuje na duży wpływ dynamiki ablacji lodowca. Podczas ostatniego etapu deglacjacji część ozu pokryta została diamiktonem. W ozie stwierdzono liczne struktury deformacyjne. Osady zostały przemieszczone pionowo na wysokość ponad 8 m. Stanowią one zapis wytapiania się pogrzebanych brył martwego lodu w osadach jądra ozu. Wytapianie się brył powodowało pionowe przemieszczanie się osadów i powstawanie tzw. dead-ice structure. Złożoność genezy ozów jest charakterystyczna dla obszarów polodowcowych Polski, gdzie większość ozów powstaje w rynnach subglacjalnych. Liczne badania potwierdzają znacznie częstsze występowanie następstwa facji subglacjalnego tunelu i otwartej rozpadliny w ozach powstających w tunelach typu N niż typu R. Wskazuje to na dużo większą odmienność procesów podczas różnych etapów formowania się ozów na nieskonsolidowanym oraz litym podłożu.
Źródło:
Acta Universitatis Lodziensis. Folia Geographica Physica; 2021, 20; 13-25
1427-9711
2353-6063
Pojawia się w:
Acta Universitatis Lodziensis. Folia Geographica Physica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heavy minerals as a tool to reconstruct river activity during the Weichselian glaciation (Toruń Basin, Poland)
Autorzy:
Weckwerth, Piotr
Chabowski, Marek
Powiązania:
https://bibliotekanauki.pl/articles/94678.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
heavy minerals
ice-marginal valley
river-discharge regime
channel-pattern transformation
Toruń Basin
Weichselian
ciężkie minerały
pradolina
dorzecze Torunia
zlodowacenie północnopolskie
Opis:
The heavy-mineral composition of the Weichselian fluvial successions deposited by an ephemeral meandering river and by a sand-bed braided river in the Toruń Basin (central Poland) was analysed. On the basis of a lithofacies analysis, in combination with the composition of the heavy-mineral assemblages, the fluvial processes and river-channel morphology were reconstructed. This allows determining the provenance of the fluvial deposits and the rivers’ discharge regimes. A model is proposed which can explain the changes in the amount of individual minerals in the fluvial sediments of different ages under the conditions of the oscillating Scandinavian ice sheet. The model assumes that, during the ice-sheet advances, the proglacial streams supplied large amounts of heavy minerals that were less resistant to mechanical abrasion. During the main phase of the ice-sheet retreat, the distance between the ice sheet and the Toruń Basin increased, and the amount of non-resistant minerals diminished as a result of sediment reworking in proglacial rivers. Due to the unique location of the Toruń Basin at the front of the Scandinavian ice sheet during the Weichselian glaciation, the heavy-mineral assemblages in the fluvial deposits form a valuable tool for the recognition of the ice-sheet extent.
Źródło:
Geologos; 2013, 19, No. 1-2; 25-46
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geology of the lower Vistula region, northern Poland
Autorzy:
Gałązka, D.
Marks, L.
Powiązania:
https://bibliotekanauki.pl/articles/1182753.pdf
Data publikacji:
2009
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
transgresje lądolodu
morze eemskie
zlodowacenie Wisły
czwartorzęd
Dolina Dolnej Wisły
Polska
ice sheet advances
Eemian sea
Vistulian
Quaternary, Lower Vistula Region
Polska
Opis:
Depression in the Quaternary bedrock in the Lower Vistula Region was a main route for the Scandinavian ice sheets advancing into the Polish Lowland. At the end of the Elsterian Glaciation the receding ice sheet dammed the meltwaters in the Lower Vistula Valley and in its vicinity. The Holstein sea presumably occupied the Gulf of Gdańsk as indicated by brackish deposits of this age in the Kaliningrad District. During the Eemian Interglacial an extensive sea bay existed in the Lower Vistula Region. The Lower Vistula Region is a stratotype area for the Vistulian Glaciation (Weichselian), with several ice sheet advances, also before the Last Glacial Maximum.
Źródło:
Polish Geological Institute Special Papers; 2009, 25; 13-20
1507-9791
Pojawia się w:
Polish Geological Institute Special Papers
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Depositional conditions of the Upper Younger Loess during the Last Glacial Maximum in central and eastern Europe
Autorzy:
Dzierżek, Jan
Lindner, Leszek
Chlebowski, Roman
Szymanek, Marcin
Bogucki, Andriy
Tomeniuk, Olena
Powiązania:
https://bibliotekanauki.pl/articles/24024703.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
North European Loess Belt
Vistulian glaciation
aeolian processes
palaeowind circulation
heavy minerals
północnoeuropejski pas lessowy
zlodowacenie Wisły
procesy eoliczne
minerały ciężkie
Opis:
This paper is a summary of the results of research on the accumulation conditions of the Upper Younger Loess (LMg) in Poland and Bug loess (bg) in Ukraine from the maximum stage (MIS 2) of the Vistulian (Weichselian) Glaciation in central and eastern Europe. These studies included an analysis of the morphological (topographic) situation of the loess cover, its grain size and heavy mineral composition, the preserved structures of loess sedimentation as well as mollusc and pollen analyses of this loess. They revealed that the accumulation of Upper Younger Loess (UYL) might have been more dependent on the prevailing moisture conditions than previously thought. These conditions could have been caused by cold air masses from an ice sheet and warm air masses from the Mediterranean Sea and Atlantic coming together in the Carpathians and the Holy Cross Mountains and favouring the formation of dust storms and precipitation. In this process, a loading of loess dust (formed from local rocks weathering in periglacial conditions) by atmospheric moisture particles was especially significant. The moist substrate not only favoured the periodic development of vegetation and molluscs but also enabled the interception of dust and the accumulation of an increasingly thick loess cover. Westerly and south-westerly winds predominated in the UYL as indicated by the topographic position of loess patches and the mineral composition of the studied loess. Periodically an increased air circulation from the east and northeast occurred.
Źródło:
Acta Geologica Polonica; 2022, 72, 4; 369--389
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
East-Siberian coregonid fishes: their occurrence, evolution and present status
Autorzy:
Yakhnenko, V. M.
Mamontov, A. M.
Luczynski, M.
Powiązania:
https://bibliotekanauki.pl/articles/363220.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
system wodny
zlodowacenie
aktywność tektoniczna
jezioro
pochodzenie
coregonidy
specjacja
sympatryczność
allopatry
coregonids
glaciation
origin of lakes
speciation
sympatry
tectonic activity
water systems
Opis:
Coregonid fishes (coregonids) (Salmonidae, Coregoninae) of Siberia show immense morphological and ecological variability, what is reflected in their complex interspecific and intraspecific structure: i.e. occurrence of numerous species, forms and endemic species. Studies of the coregonids of Siberia is crucially important for understanding of their origin, taxonomy and evolution. We have analysed electrophoretically some 13 enzyme systems from over 20 samples of East-Siberian coregonids. This paper was intended as an introduction to a number of primary papers that are planned that will describe the biological and genetic characteristics of studied populations.
Źródło:
Environmental Biotechnology; 2008, 4, 2; 41-53
1734-4964
Pojawia się w:
Environmental Biotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studium sedymentologiczne form glacimarginalnych okolic wsi Zamoście (Polesie Wołyńskie, Ukraina NW)
Autorzy:
Renda, Andrij
Powiązania:
https://bibliotekanauki.pl/articles/763116.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
glacimarginal forms
lithofacial analysis
end moraines
Dnieper Glaciation
Volhynian Polesie
NW Ukraine
formy glacimarginalne
analiza litofacjalna
moreny czołowe
zlodowacenie dniepru
Polesie Wołyńskie
Ukraina NW
Opis:
Near Zamostya in the Volhynian Polesie (NW Ukraine) a first sedimentological attempt was made to explain the origin of glacimarginal forms forming sub-parallel trains. They belong to themost typical elements of the Polesie glacial relief from the Dnieper Glaciation. Lithofacial analysis was used during the research. Based on geomorphological situation of the glacimarginal forms andlithofacial features of their deposits, the forms were classified as end moraines documenting one of the stagnation phases of ice-sheet recession during the Dnieper Glaciation.
Artykuł nie zawiera abstraktu w języku polskim
Źródło:
Annales Universitatis Mariae Curie-Sklodowska, sectio B – Geographia, Geologia, Mineralogia et Petrographia; 2013, 68, 2
0137-1983
Pojawia się w:
Annales Universitatis Mariae Curie-Sklodowska, sectio B – Geographia, Geologia, Mineralogia et Petrographia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heavy and light minerals as a tool for reconstructing depositional environments: an example from the Jałówka site (northern Podlasie region, NE Poland)
Autorzy:
Woronko, Barbara
Rychel, Joanna
Karasiewicz, Mirosław T.
Ber, Andrzej
Krzywicki, Tomasz
Marks, Leszek
Pochocka-Szwarc, Katarzyna
Powiązania:
https://bibliotekanauki.pl/articles/94625.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
heavy minerals
quartz grain
periglacial processes
source deposits
Vistulian glaciation
NE Poland
minerały ciężkie
ziarna kwarcu
procesy peryglacjalne
złoża źródłowe
zlodowacenie Wisły
Polska północna
Opis:
Part of northern Podlasie (NE Poland), shaped during the Wartanian stadial of the Odranian glaciation (Saalian), was situated in the periglacial zone during the Vistulian (Weichselian) glaciation. Both landforms and sediments were affected by the periglacial conditions. This is recorded at the Jałówka site, at the floor of a dry valley, where mineral deposits of 4.13 m thick, overlying organic deposits from the Eemian interglacial, were examined. These mineral deposits form four units, from bottom to top: a fluvial unit (I), a loess-like unit (II), a solifluction unit (III), and an aeolian unit with ice wedges (IV) on top of unit III. The heavy and light minerals were analysed, as well as the geochemistry, in order to find out about the parent material and to reconstruct the climatic conditions during deposition. The mineral analysis indicates that the Saalian till was predominantly derived from shallow-marine deposits; erosion accompanied by sorting of the heavy minerals took place on the basis of their mass and grain size. The original material of the till seems therefore to be sedimentary rocks from the eastern Central Baltic Basin. This material became strongly weathered under the periglacial conditions, resulting in the destruction of the quartz grains, as well as in leaching, leading to complete decalcification of the deposits. Aeolian activity resulted in infilling of ice wedges and the creation of thin layers. The intensity and the duration of these processes was limited, so that the effects of the aeolian abrasion are insignificant. Neither resulted the aeolian activity in significant reshaping of the landscape.
Źródło:
Geologos; 2013, 19, No. 1-2; 47-66
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-11 z 11

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies