The Open UniversitySkip to content
 

The Hidden Hazard Of Melting Ground Ice In Northern Iceland

Morino, Costanza (2018). The Hidden Hazard Of Melting Ground Ice In Northern Iceland. PhD thesis The Open University.

Full text available as:
[img]
Preview
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (15MB) | Preview
Google Scholar: Look up in Google Scholar

Abstract

This thesis explores the morphology, dynamics and causes of landslides and debris flows in mountainous regions of northern Iceland. The primary objectives are to define the initiation and evolution of Icelandic landslides and debris flows, and to understand the link between ground-ice thaw and rapid mass movements. Slopes are predicted to react more intensely to global warming, so improving our knowledge of rapid mass movements in cold environments, which are even more sensitive to climate change, is crucial, as they could pose at risk local population in Iceland and other mountainous periglacial areas.

I first perform a detailed study of debris flows in north-western Iceland, distinguishing through quantitative geomorphological methods the different mechanisms of debris-flow initiation and the associated geomorphic features. The approach of this study is easily applicable to similar settings, and its results could help in anticipating new potentially destructive events. Secondly, I describe and quantify the morphometric characteristics of two landslides in northern Iceland, whose source materials comprised ground ice-cemented deposits. This study reveals different dynamic landslide processes and the crucial role of thawing ground ice in landslide emplacement. I then analyse meteorological and seismic data near these two landslides. I define and distinguish precipitation, seismic activity and permafrost degradation as the preparatory and triggering factors for the failures. Finally, through a geomorphic approach I analyse molards, conical mounds of debris that I found in both landslides deposits. I show conclusive evidence that molards form from thawing of blocks of ice-rich sediments that degrade into cones of debris. I demonstrate that molards are the ‘fingerprint” of permafrost degradation, and their different morphology and distribution can reveal different types of landslide processes in periglacial terrains.

This thesis widens our knowledge of the conditions and processes controlling rapid mass movements in cold environments, which is crucial in the perspective of hazard assessment, and opens up new avenues for the study of potentially hazardous geomorphic responses of cold landscapes to changing climate conditions.

Item Type: Thesis (PhD)
Copyright Holders: 2018 The Author
Keywords: landslides; debris avalanches; geology; climatic changes
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM)
Faculty of Science, Technology, Engineering and Mathematics (STEM) > Environment, Earth and Ecosystem Sciences
Item ID: 57836
Depositing User: Costanza Morino
Date Deposited: 10 Dec 2018 09:35
Last Modified: 17 Aug 2019 03:48
URI: http://oro.open.ac.uk/id/eprint/57836
Share this page:

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU