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The dynamics of the north-western Laurentide Ice Sheet margin
Stoker, Benjamin James ; Margold, Martin (advisor) ; Darvill, Christopher (referee) ; Nývlt, Daniel (referee)
The Laurentide Ice Sheet (LIS) was the largest ephemeral ice sheet in the Northern Hemisphere, reaching its all-time maximum during the last glacial cycle (~115 ka to ~11.7 ka) as it coalesced with the Cordilleran and Innuitian ice sheets over northern North America and the Canadian Arctic Archipelago. At its maximum extent it was comparable in size to the modern-day Antarctic Ice Sheet and may provide a useful analogue for understanding the long-term dynamics of ice sheets. There are considerable regional variations in our understanding of the deglaciation of the LIS. In particular, the northwestern LIS remains one of the most poorly understood sectors, as the latest reconstruction of this sector dates to the early 1990s and empirical constraints on the timing of deglaciation are sparse. In this thesis, I reconstruct the deglaciation of the northwestern LIS from its local Last Glacial Maximum (LGM) position using numerical dating methods and glacial geomorphological mapping. I use a combination of high-resolution digital elevation models (DEMs) and satellite imagery to map the glacial geomorphology of much of the Northwest Territories, Canada, and reconstruct the ice margin retreat patterns, ice flow dynamics, and interaction of the northwestern LIS with other ice masses. This new information is...
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Geomorphological evidence of the Scandinavian glaciation in the Moravian Gate
Pavurová, Zuzana ; Engel, Zbyněk (advisor) ; Nývlt, Daniel (referee)
Geomorphological evidence of the Scandinavian glaciation in the Moravian Gate Abstract This thesis is aimed at area in the Moravian Gate which was covered by continental ice sheets during the Quaternary. The goal of this thesis is to analyze relief and ice-margin landforms in the Moravian Gate. Main parts of this thesis are: current views on the extent of glaciated area, definition ice-marginal landforms, methods my fieldwork, results and discussion. Maps and graphs were created as a part of this thesis. Present relief is very different from pleistocene relief. It is difficult find ice-margin landforms. I agree with extent of pleistocene ice sheet glaciations from Tyráček (2006).
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Reconstructing the central sector of the Cordilleran Ice Sheet
Dulfer, Helen Elizabeth ; Margold, Martin (advisor) ; Ely, Jeremy (referee) ; Nývlt, Daniel (referee)
The Quaternary Period (last 2.6 Ma) was a time of increased climate oscillation that resulted in the repeated growth and decay of Northern Hemispheric ice sheets. During this period the Cordilleran Ice Sheet (CIS) repeatedly covered mountainous western North America and attained a volume and area similar to the present-day Greenland Ice Sheet. At the Last Glacial Maximum (LGM) the CIS formed part of the North American Ice Sheet Complex (NAISC), coalescing with the Laurentide Ice Sheet east of the Rocky Mountains. However, the high relief bed and remote location mean there are few empirical constraints pertaining to the nature of ice sheet build-up and retreat in the central region of the CIS, in northern British Columbia, making it one of the least understood ephemeral Pleistocene ice sheets. In this thesis I use glacial geomorphology and quantitative dating techniques to reconstruct the advance of the CIS to its LGM position and subsequent retreat. I use high resolution remotely sensed data to create a detailed map of glacial landforms for the central sector of the CIS, beneath the local LGM ice divide (55řN to 60řN; paper I). Seven landform categories were mapped: ice flow parallel lineations, moraines (CIS outlet glacier moraines, Late Glacial moraines and moraines of unknown origin), meltwater...
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Recent development of Ferdinandbreen valley glacier in Petuniabukta (Svalbard)
Tomíček, Jiří ; Engel, Zbyněk (advisor) ; Nývlt, Daniel (referee)
Svalbard archipelago is located halfway between the Northern coast of Norway and the North Pole. About 60 % of Svalbard area is covered by glaciers of many types, from small cirque to large ice caps. Retreat of most glaciers in Svalbard has been recorded since the Little Ice Age at the end of the 19th century. Deglaciation of Svalbard landscape is connected with significant changes of natural environment, such as changes of erosion and acumulation processes, climate change or beginning of vegetation succession. This thesis aims to establish the elementary glaciological parameters of valley glacier Ferdinandbreen located in Petuniabukta, central part of Spitsbergen, by analyzing remote sensing data and field GPR and (d)GPS survey and evaluate it's evolution between 1960 - 2014. Glacier's length and area have been based on aerial imagery of years 1960, 1990, 2009 and GPS measurements in 2014. Ice thickness and volume have been derived from GPR measurements. The length of the glacier in 2014 was 1,401 km, area 0,560 km2 and volume 6 561 684 m3 . The maximum measured ice thickness in 2014 was 42,5 m. During the period 1960 - 2014, the length of the glacier had been reduced by 45 % and area by 69 %, ice thickness had been reduced by 23,5 m during the period 1990 - 2014. Recorded retreats of length, area...
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Geomorphological evidence of the Scandinavian glaciation in the Moravian Gate
Pavurová, Zuzana ; Engel, Zbyněk (advisor) ; Nývlt, Daniel (referee)
Geomorphological evidence of the Scandinavian glaciation in the Moravian Gate Abstract This thesis is aimed at area in the Moravian Gate which was covered by continental ice sheets during the Quaternary. The goal of this thesis is to analyze results of work of Tyrá ček (2006). Main parts of this thesis are: current views on the extent of glaciated area, definition ice-marginal landforms, methods my fieldwork, results and discussion. Maps and graphs were created as a part of this thesis. Data was processed using MapInfo Professional 7.0 SCP software, ArcGIS 9 software a Microsoft Office Excel 2003.
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Holocene history of Arctic lakes
Roman, Matěj ; Nývlt, Daniel (advisor) ; Kavan, Jan (referee)
Holocene history of Arctic lakes Abstract Palaeolimnology in the Arctic has achieved a considerable progress in the last decades. The Arctic has changed markedly since the Last Glacial and glacier retreats caused formation of a great number of diverse lake types. Lakes of glacial origin, thermokarst lakes, fluvial lakes and lakes on raised beaches occur most often here. Palaeolimnological methods applied to the high latitude areas are used for the study of the history of individual lakes. Methods of correlation of sedimentary cores and basic interpretation of proxy records such as magnetic susceptibility, diatom biostratigraphy and content of carbon and sulphur were applied on sediments of Garmaksla Lake, Svalbard Archipelago. Climatic and ecological shifts including the Little Ice Age termination and recent warming were registered in proxy values. Keywords: lakes, palaeolimnology, palaeoclimatology, environmental changes, Holocene, Arctic
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Response of selected rivers of the Bohemian Massif to lithological and structural conditions
Flašar, Jan ; Nývlt, Daniel (advisor) ; Kalvoda, Jan (referee)
Three groups of streams were selected in the area of the Bohemian Massif: the Berounka river with its source streams; the Vltava river with its tributaries the Malše and the Lužnice; the Labe river with its tributaries the Cidlina, the Bystřice and the Javorka. The lithological and tectonical influences to several parameters of the streams were studied. These parameters include: stream gradient, orientation of the stream and sinuosity of the stream. Data were obtained from digital elevation models, aerial photographs, topographical and geological maps. The longitudinal profiles of the streams (in the combination with geological cross-sections), the SL indexes and the gradient/sinuosity graphs were created on the basis of the obtained data. These tools were used for evaluation of the influence of lithology and the tectonics to the streams. The evolution of the streams and the stream-groups was evaluated and compared as well. A strong influence of lithology on the stream gradient was found on most of the analysed streams. The tectonic situation, on the contrary, had strong influence on the orientation of the streams, especially in the resistant rocks. Also, there were selected areas, where was a higher probability of quaternary vertical movements influencing the streams (mountainous areas of the Novohradské...
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Assessment of the suitability of the site for the location of the underground\nof SNF and RAW repository in terms of long-term safety - Horka site
Havlová, V. ; Pertoldová, J. ; Bukovská, Z. ; Hroch, T. ; Štědrá, V. ; Uhlík, J. ; Říha, J. ; Červinka, R. ; Baier, J. ; Buriánek, D. ; Černý, M. ; Dudková, I. ; Dušek, K. ; Franěk, J. ; Gondolli, J. ; Hokr, M. ; Holeček, J. ; Jankovec, J. ; Jelének, J. ; Jelínek, J. ; Kachlíková, R. ; Kaláb, Zdeněk ; Klajmon, M. ; Kolomá, K. ; Kouřil, M. ; Královcová, J. ; Kučera, R. ; Kunceová, E. ; Maryška, J. ; Milický, M. ; Nývlt, D. ; Ondra, P. ; Pacherová, P. ; Polák, M. ; Rapprich, V. ; Rukavičková, L. ; Steinová, J. ; Svoboda, J. ; Šír, P. ; Švagera, O. ; Vašíček, R. ; Vavro, Martin ; Vopálka, D. ; Zeman, J. ; Zeman, O.
This report summarises outline of a report for evaluation of the sites‘ suitability for the emplacement of a deep geological repository on the basis of the archive information and the geological survey conducted from surface.\nSites are evaluated according to the following criterion categories\n1. Geological characteristics of the site\n2. Hydrogeologic characteristics of the site\n3. Transport characteristics of the the site\n4. Site stability\n5. Factors, increasing probability of human intrusion into the site\n6. Acceptability of enginnered barrier properties under site conditions
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Assessment of the suitability of the site for the location of the SNF and RAW deep geological repository in terms of long-term safety - Dukovany - West site\n(EDU-Z).
Havlová, V. ; Pertoldová, J. ; Bukovská, Z. ; Hroch, T. ; Štědrá, V. ; Jankovec, J. ; Říha, J. ; Červinka, R. ; Černý, M. ; Dudková, A. ; Dušek, K. ; Franěk, J. ; Gondolli, J. ; Gvoždík, L. ; Hokr, M. ; Holeček, J. ; Hrdličková, K. ; Jelének, J. ; Jelínek, J. ; Kachlíková, R. ; Kaláb, Zdeněk ; Klajmon, M. ; Kolomá, K. ; Královcová, J. ; Kouřil, M. ; Kryštofová, E. ; Kučera, R. ; Kunceová, E. ; Maryška, J. ; Milický, M. ; Nývlt, D. ; Ondra, P. ; Pacherová, P. ; Polák, M. ; Rapprich, V. ; Rukavičková, L. ; Sedláčková, I. ; Vašíček, R. ; Vavro, Martin ; Vopálka, D. ; Uhlík, J. ; Zeman, J. ; Zeman, O.
This report summarises outline of a report for evaluation of the sites suitability for the emplacement of a deep geological repository on the basis of the archive information and the geological survey conducted from surface.\nSites are evaluated according to the following criterion categories\n1. Geological characteristics of the site\n2. Hydrogeologic characteristics of the site\n3. Transport characteristics of the the site\n4. Site stability\n5. Factors, increasing probability of human intrusion into the site\n6. Acceptability of enginnered barrier properties under site conditions
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