Subglacial paleolakes in Norway
Hundreds of subglacial lakes have been discovered beneath the Antarctic ice sheet over the past 20 years. Were subglacial lakes also present beneath the Fennoscandian ice sheets? If so, how have the existence and drainage of such lakes affected the landscape and the geomorphology of Norway?
a) Mapping of Rogen (ribbed) moraines and flutes
One work hypothesis is that Rogen moraines were formed in regions of shallow subglacial lakes, and that very well developed flute areas were formed in water saturated till downstream of these shallow lakes.
To investigate this hypothesis further, a digital inventory of both Rogen moraines and flutes must be formed using existing maps and aerial imagery (e.g. www.norgeibilder.no). Similar studies have been done before locally, but probably needs to be updated and transferred into a GIS environment.
A second step is to address terrain parameters in areas of Rogen moraines and flutes. Is it possible to identify a system in the distribution of the landforms, e.g. do they exist on both concave and convex ground, below or above certain altitudes, is there a threshold of slope angle etc?
A third step is to identify paleo-ice movement in areas of Rogen moraines and flutes, based on existing reconstructions of the Fennoscandian ice sheet.
Supervisors: Karianne S. Lilleøren, Bernd Etzelmüller
Requirements: Knowledge of geomorphology, DEM, GIS-analysis. Field work is optional.
b) Mapping of canyons and modelling of paleo-ice sheet thickness
If large subglacial lakes existed beneath the Fennoscandian ice sheet, they must have been drained occasionally. Several topographically unmotivated canyons exist in Norway, and may be a result of violent drainage of such lakes (e.g. Hellemojuvet, Nordland, Alta canyon, Finnmark ++).
An inventory of the distribution of canyons could be used to identify candidates of canyons formed by drainage of subglacial lakes, and can be used further to investigate the regional distribution of such paleolakes.
A second and important step is then to reconstruct the ice-thickness distribution required to allow drainage through the identified canyons; and also infer possible locations of the corresponding subglacial lakes.
Supervisors: Karianne S. Lilleøren, Thomas V. Schuler, Bernd Etzelmüller
Requirements: Knowledge of geomorphology/glaciology, DEM/GIS analysis, some scripting