There is a unique variation of land forms and geological phenomena in the world heritage area, because the bedrock has been shaped by changing ice sheets and glaciers for millions of years.
Sporadic soil layers and winding deposits in terminal and lateral moraines show that
landscape was shaped during the last ice ages. The most obvious results of the glacial processes include the clearly
demarcated, deep and narrow fjords. These fjords are valleys that the ice excavated, that are now filled with water. Hanging valleys and the characteristic fish-hook valleys (agnor valleys), that are formed when mountain structures capture rivers, are testimony to the long history that is “archived” by the local remains of older land forms, also those from before the ice ages.
The Geirangerfjord area contains excellent examples of several features that characterise a fjord landscape from which the glaciers have retreated relatively recently – a landscape which is still very much “alive”, and is actively changing due to geological processes.
In this area there is a relatively thin and unevenly dispersed layer of superficial deposits. Stone runs are common in some of the highest mountains (e.g. Torvløysa and Geitfonnegga), and these probably protruded as
superficial deposits. There are also thick soil deposits, and important examples of those are
deposits in valleys that run in a direction perpendicular to the main direction of the glaciers (e.g. Dyrdalen, Herdalen
and Skagedalen). An important terminal moraine ridge that identifies the extent of glacial valleys
formed during the younger dryas, crosses over the Sunnylvsfjorden and the mouth of Geirangerfjorden
When the main glacier melted, the melt water created large delta at the end of the fjord (e.g. in Geiranger). These deltas have expanded to gradually lower levels as the sea level has changed when the ice melted and the land continued to rise.
During the last Ice Age, the Fennoscandian ice sheet expanded greatly and reached a thickness of several hundred metres over parts of Norway. The weight of the ice depressed the land. When the ice melted at the end of the Ice Age, this pressure was relieved and the land began to rise. There is generally little evidence of former
shorelines in the area due to the extremely steep topography. However, the evolution of the delta system
in Geiranger illustrates the relative drop in sea level following deglaciation .
Geology and landforms
- How the glaciers formed the landscape
- A living landscape – The Quaternary (1.8–0 million years)
- Landslides and Avalanches
- Rivers and waterfalls
- From open ocean to narrow fjord
- A history written in stone (1600–100 million years)
- New rising – tertiary (65–2.5 million years)
- The geology of the bedrock is the key to history