The Reconstruction of Ice Sheet Movements around the Arctic Ocean from Bathymetric dataset
With the advent of advance acoustic devices, scientists have been able to observe and describe some of the activities and extent of the previous ice sheet or ice masses on the Arctic Ocean during the past interglacialglacial periods. Multibeam and sub bottom pro- �les from numerous expeditions have...
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| Format: | Thesis |
| Language: | unknown |
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2015
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| Online Access: | https://epic.awi.de/id/eprint/42791/ https://hdl.handle.net/10013/epic.49367 |
| Summary: | With the advent of advance acoustic devices, scientists have been able to observe and describe some of the activities and extent of the previous ice sheet or ice masses on the Arctic Ocean during the past interglacialglacial periods. Multibeam and sub bottom pro- �les from numerous expeditions have revealed ice mass movements on the Arctic Ocean sea oor. These movements of the massive ice masses impacted on the sea oor thereby creating in plough marks, utes, mega scale glacial lineations (MSGLs), scours and seabed sediments. Expedition cruises with ice breakers, mounted with multibeam sonar and sub bottom acoustic devices have been carried out at various times by di�erent research in- stitutes. Some of the areas of glacial activities on the Arctic Ocean seabed were identi�ed in some publications. They include areas around the Chukchi borderland (Jakobsson et al, 2008b), Yermak plateau (Dowdeswell et al, 2010), North Svalbard (Dowdeswell et al., 2010), Lomonosov ridge (Jakobsson, M., 1999), Northeast Greenland (Evans et al., 2009), Amundsen Gulf (Stokes et al., 2006). For this thesis multibeam bathymetric data from up to 20 years ago were inspected and data containing features of glacial erosion on the sea oor were set aside and processed further. The data was converted into Geographic Information System (GIS) readable formats and ArcGIS software was used to visualize and digitize the features seen. Glacial maps of the seabed were created which shows various glacial features seen as line features (Appendix A). Previous ice sheet extent was reconstructed by obtaining data from publi- cations, georeferencing the data and digitizing the data on-screen. The orientation of the glacial features such as moraines, drumlins, MSGLs, utes and plough marks seen was used to reconstruct the likely movement of the ice sheet during the last glacial maximum (LGM). The orientation of the glacial features was also used to identify the probable origin of the sea oor scouring ice sheet on the Arctic Ocean. The results obtained are discussed in chapters 5 and 6. |
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