Rock-avalanche hazard in Møre & Romsdal, western Norway
MetadataShow full item record
- NGI articles 
Flood waves generated by large rock avalanches have caused major disasters in Norway. Many of these events are restricted to a relatively limited zone in the counties Møre & Romsdal and Sogn & Fjordane. Geological studies confirm that this zone has been affected by large-scale rock avalanches throughout the postglacial period. The number of rock-avalanche events is much higher than expected, and many of them are from the latest part of the postglacial period (the last 5000 years), thus in contrast to the general assumption that most of these events occurred shortly after the deglaciation. Rock avalanches and related flood waves often represent a higher risk than other types of avalanches in the region, due to the potential of causing extensive damage. It can be concluded that the avalanche probability limit of 10-3 pr. annum which is used for normal buildings in Norway, is not applicable for rock-avalanche hazard. The study indicates that rock-avalanche hazard should be taken into account in several inhabited areas. More work needs to be done in order to produce hazard-zone maps.