Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 19 of 19 for “"Ice stream"”.
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Tidally Forced Marine Ice Stream Instabilities and Their Consequences
… 10-kyr deglaciation. Since its discovery in ice cores recovered from Greenland, the rapid deglaciation has proven mysterious. I present a novel explanation for this phenomenon, wherein the deglaciation of the Laurentide ice sheet is accelerated by the rapid collapse of marine-terminating ice …
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The influence of subglacial hydrology on the flow of West Antarctic ice streams
… hydrology is known to influence the flow of ice. However, difficulty in accessing the base of large ice sheets has made determining the interaction between ice streams, basal sediment and water difficult to discern. The aim of this thesis is to determine the influence of subglacial hydrology …
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Submarine Landforms and Late Quaternary Ice Flow in Hinlopen Strait, Northern Svalbard Margin
… trough is thought to have been occupied by an ice stream which flowed north across the continental slope (Ottesen et al., 2007). This project is concerned with examining the submarine landforms and acoustic stratigraphy of this palaeo-ice stream with a view to furthering our understanding of …
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Reflection seismic investigations of the Canadian Beaufort Sea margin, Arctic Ocean
… troughs, representing locations of former ice streams draining a 1000 km-long section of the Laurentide Ice Sheet (LIS), are examined: the Mackenzie, Amundsen Gulf and M'Clure Strait systems. These palaeo-ice streams operated during the last, Late Wisconsinan glacial maximum, as well as …
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Reconstructing ice dynamics in the central sector of the last British-Irish Ice Sheet
… and Scottish borders) of the last British-Irish Ice Sheet exhibits a palimpsest glacial geological and geomorphological signature characteristic of multi-phase ice flow and ice-marginal fluctuations. Despite its influential position at the heart of the British-Irish Ice Sheet, sourced from major …
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Relating surface and bed properties of Antarctic ice streams
Theoretical models predict that fast-flowing ice streams transmit information about their bedrock topography most efficiently to the surface for two distinct windows of length-scales. Previous studies have shown a good transfer for basal undulations with wavelengths longer than 103 ice thicknesses. …
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Glacial Geomorphology of southern Alberta, Canada
… from the Last Glacial Maximum three terrestrial ice streams within the south western sector of the Laurentide Ice Sheet competed and coalesced in southern Alberta; the High Plains Ice Stream (HPIS), Central Alberta Ice Stream (CAIS) and the east lobe. The ice streams are characterised by smoothed …
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Subsurface Geophysical Investigations of Oneida Lake Ny: Insights Into Ice Sheet Processes and Deglaciation At Termination I
<p>Reconstructing the retreat of the Laurentide Ice Sheet (LIS) provides insight into understanding end-Pleistocene climate, a critical set of boundary conditions prior to the onset of Holocene climates that were optimal for human dispersal and societal growth. Constraining ice sheet dynamics, …
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Ice dynamics and glacial history from remote sensing of the Seno Skyring-Seno Otway-Strait of Magellan region, southernmost Patagonia
… the advance and retreat of the Patagonian ice sheet over a number of glacial cycles. The well-preserved landform assemblages and sediments that have been left behind comprise one of the longest and most complete records of Quaternary glaciations in the world. Despite this, little is known …
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Late Devensian ice sheet dynamics and the deglaciation of the Hebridean shelf, western Scotland, UK
The reconstruction of past ice sheet dynamics can shed a light on long-term ice sheet activity, and in turn provide constraints on the response of modern ice sheets to climate change. The Hebrides Ice Stream (HIS) flowed across part of the western Scottish shelf to the shelf-break during the last …
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Iceberg-keel ploughmarks on the seafloor of Antarctic continental shelves and the North Falkland Basin: implications for palaeo-glaciology
The use of iceberg-keel ploughmarks as proxy indicators of past and present iceberg morphology, keel depth and drift direction has seldom been approached in the southern hemisphere. Using high-resolution multi-beam swath bathymetry of the mid-shelf Pine Island Trough and outermost Weddell Sea shelf …
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Weichselian glaciations in the middle Notec River region, northwest Poland
This thesis presents results of studies on the ice flow pattern and ice movement mechanism during the Weichselian glaciations in the middle Notec River area, NW Poland. A new lithostratigraphy of the study area has been established, based on correlation of stratigraphical position, clast lithology, …
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Late Quaternary ice-ocean interactions in central West Greenland
… of the interactions between the Greenland Ice Sheet and climate is critical to understanding the possible impacts of future global warming, including ice sheet contribution to global sea-level rise and perturbations to ocean circulation. Recent acceleration, thinning and retreat of major …
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Submarine Geomorphology of the Continental Shelves of Southeast and Southwest Greenland from Olex Data
Mass loss from the Greenland Ice Sheet remains the largest uncertainty in projections of sea level rise for the 21st century. Reconstructing the former history of the Greenland Ice Sheet during the Late Quaternary provides important constraints on how the ice sheet will behave in response to future …
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Studies of Seismic Sources in Antarctica Using an Extensive Deployment of Broadband Seismographs
… intraplate earthquakes within a stable craton), icequake events in the Transantarctic Mountains (associated with active alpine glaciers), and icequake events at calving glaciers along the coastline. In West Antarctica I find tectonic earthquakes, icequakes, and tectonic events related to …
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Seafloor ploughmarks on the mid-Norwegian continental shelf reveal iceberg trajectories during the last glacial period
… linear to curvilinear depressions interpreted as iceberg ploughmarks were mapped across the mid-Norwegian continental shelf using high-resolution swath bathymetry data. The orientation and morphology of each iceberg ploughmark was calculated and analysed, with features being up to 30 km long and …
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The Response of Antarctic Ice Streams to Tidal Forcing
The majority of the ice flowing from the Antarctic interior makes its way to the ocean through fast-flowing ice streams, or glaciers. Understanding what controls the speed of these streams is extremely important in predicting the overall response of ice sheets to changing climatic conditions, and …
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Evolving subglacial water systems in East Antarctica from airborne radar sounding
… environment at the base of the East Antarctic Ice Sheet is of interest to a wide range of disciplines. Stable subglacial lakes and their connecting channels remain perennially liquid three kilometers below some of the coldest places on Earth. The presence of subglacial water impacts flow of the …