Crevasse-Squeeze Ridges in Trygghamna, Svalbard
Glacial geologists have been discussing the processes behind the formation of Crevasse-Squeeze Ridges (CSRs) since they were first described from the forefield of Eyjabakkajökull, Iceland, in the mid 1980s. To date, CSRs are, together with concertina eskers, the only landforms that have been describ...
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ftskemman:oai:skemman.is:1946/26725 2023-05-15T16:21:46+02:00 Crevasse-Squeeze Ridges in Trygghamna, Svalbard Daniel Ben-Yehoshua 1989- Háskóli Íslands 2017-01 application/pdf http://hdl.handle.net/1946/26725 en eng http://hdl.handle.net/1946/26725 Jarðfræði Jöklarannsóknir Landmótun Setlög Thesis Master's 2017 ftskemman 2022-12-11T06:59:00Z Glacial geologists have been discussing the processes behind the formation of Crevasse-Squeeze Ridges (CSRs) since they were first described from the forefield of Eyjabakkajökull, Iceland, in the mid 1980s. To date, CSRs are, together with concertina eskers, the only landforms that have been described exclusively in the forefields of surge-type glaciers. However, much remains to be learned about these ridges and their glaciological significance. This thesis describes geometrical and transverse sediment ridges appearing after surge events of polythermal glaciers in Trygghamna, West Svalbard. In order to understand the geomorphic context of these landforms, detailed maps were produced via remote sensing and field mapping. These maps illustrate striking differences in CSR configurations found in marine and terrestrial settings. Historical images from 1936 were used to compare the geometry of former glacier surface structures with mapped CSRs. Furthermore, analysis of CSRs in cross-sections sheds light on the architecture and sedimentology of these formations. Results from Trygghamna suggest that basal till was squeezed into basal crevasses during a surge and transported englacially before deposition. Mapped landform assemblages suggest that at least two glaciers in Trygghamna have surged in the past. Additionally, CSRs are observed in an area of a former glacial shear-zone between a surge-type and a non-surge-type glacier. A conceptual model for the formation and preservation of CSRs in Trygghamna is proposed. The results of this thesis not only further contemporary understanding of CSRs in Trygghamna, but may also apply to large-scale glacial or ice stream settings. Thesis glacier glacier Iceland Svalbard Skemman (Iceland) Eyjabakkajökull ENVELOPE(-15.600,-15.600,64.667,64.667) Svalbard Trygghamna ENVELOPE(13.819,13.819,78.246,78.246) |
institution |
Open Polar |
collection |
Skemman (Iceland) |
op_collection_id |
ftskemman |
language |
English |
topic |
Jarðfræði Jöklarannsóknir Landmótun Setlög |
spellingShingle |
Jarðfræði Jöklarannsóknir Landmótun Setlög Daniel Ben-Yehoshua 1989- Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
topic_facet |
Jarðfræði Jöklarannsóknir Landmótun Setlög |
description |
Glacial geologists have been discussing the processes behind the formation of Crevasse-Squeeze Ridges (CSRs) since they were first described from the forefield of Eyjabakkajökull, Iceland, in the mid 1980s. To date, CSRs are, together with concertina eskers, the only landforms that have been described exclusively in the forefields of surge-type glaciers. However, much remains to be learned about these ridges and their glaciological significance. This thesis describes geometrical and transverse sediment ridges appearing after surge events of polythermal glaciers in Trygghamna, West Svalbard. In order to understand the geomorphic context of these landforms, detailed maps were produced via remote sensing and field mapping. These maps illustrate striking differences in CSR configurations found in marine and terrestrial settings. Historical images from 1936 were used to compare the geometry of former glacier surface structures with mapped CSRs. Furthermore, analysis of CSRs in cross-sections sheds light on the architecture and sedimentology of these formations. Results from Trygghamna suggest that basal till was squeezed into basal crevasses during a surge and transported englacially before deposition. Mapped landform assemblages suggest that at least two glaciers in Trygghamna have surged in the past. Additionally, CSRs are observed in an area of a former glacial shear-zone between a surge-type and a non-surge-type glacier. A conceptual model for the formation and preservation of CSRs in Trygghamna is proposed. The results of this thesis not only further contemporary understanding of CSRs in Trygghamna, but may also apply to large-scale glacial or ice stream settings. |
author2 |
Háskóli Íslands |
format |
Thesis |
author |
Daniel Ben-Yehoshua 1989- |
author_facet |
Daniel Ben-Yehoshua 1989- |
author_sort |
Daniel Ben-Yehoshua 1989- |
title |
Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
title_short |
Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
title_full |
Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
title_fullStr |
Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
title_full_unstemmed |
Crevasse-Squeeze Ridges in Trygghamna, Svalbard |
title_sort |
crevasse-squeeze ridges in trygghamna, svalbard |
publishDate |
2017 |
url |
http://hdl.handle.net/1946/26725 |
long_lat |
ENVELOPE(-15.600,-15.600,64.667,64.667) ENVELOPE(13.819,13.819,78.246,78.246) |
geographic |
Eyjabakkajökull Svalbard Trygghamna |
geographic_facet |
Eyjabakkajökull Svalbard Trygghamna |
genre |
glacier glacier Iceland Svalbard |
genre_facet |
glacier glacier Iceland Svalbard |
op_relation |
http://hdl.handle.net/1946/26725 |
_version_ |
1766009747096469504 |