The extensive glacial landforms in the Baltic States and neighbouring countries have been used to infer the dynamic behaviour of the Scandinavian ice sheet. While pre-Weichselian phases of ice flow were identified, it was concluded that the majority of lineations within the Eastern Baltic formed during the Late Weichselian. Long (up to 21 km), well-defined lineations were found to have formed during the Late Weichselian maximum when the ice velocities were greatest. These form flow sets with a north-south trend. Lineations from the final deglaciation are shorter in length and form flow sets orientated at 170°. During the final deglaciation ice streams developed. Interstream areas generally coincide with regions of elevated bed rock. The interpretations resulting from these observations were combined with similar data from Finland to create a data set covering the area from the ice divide to beyond the limit of Weichselian ice. The spatial distribution of lineation size was examined using this data set and compared to output from a glaciological model. It was concluded that flow-parallel lineations were most likely formed by a single mechanism. The most likely mechanism was concluded to be subglacial deformation with the most active zone of lineation formation occurring within 100 km of the ice sheet margin. Variations in the frequency distribution of lineation length between Finland and the Eastern Baltic regions point to differences in the controls on lineation formation. Differences in the character of deglaciation between Finland and the Eastern Baltic were identified. Ice streams in Finland appear to have been more stable in location and about twice the width of those observed in the Eastern Baltic region. These differences may be explained by the interaction between the ice sheet and its substratum.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:660545 |
Date | January 1998 |
Creators | Perry, Jonathan Eric Hayward |
Publisher | University of Edinburgh |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://hdl.handle.net/1842/15632 |
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