Deeper Than The Continental Shelf Waters
The depth of the fjords can be greater than the near shore open sea depth because of the manner in which the fjords were formed. The fjords were carved out by glacial erosion during the Earth’s many ice ages. It has been estimated that the depth of the ice cover during these periods probably exceeded a mile in thickness (1.5 km). When you consider that the density of ice is 62.42 lb/ft3, it is easy to appreciate the immense pressure that this weight of ice would transfer to the valley bottom and the frictional forces that would gouge out and deepen the valley as the ice traveled towards the sea.
Over the past 1.5 million years, the Earth has experienced three major ice ages; we are in the fourth interglacial period currently. The fjords were formed over millennia as the colossal weight of the ice and the boulders and debris that they transported carved away the bedrock. The end of the glacier, where the glacier melted, is marked by an accumulation of this debris (it is known as “terminal moraine"). In the case of the fjords, this debris formed a plug, marking the shallowest part of the fjord, close to the seaward end. The fjords are deeper than the surrounding open seas because of the glacial excavation of the valley bottom. When the ice age ended, the glaciers retreated back up the mountains, sea levels rose, and the valleys became flooded, forming the fjords as we see them today.
Norway still has glaciers today, and they are certainly another of Norway’s land features which are well worth a visit in the summer (when the power of these rivers of ice can be easily seen). While the glaciers are a fraction of their former size, a visit in the summer is enough to provide an insight into their slow power. You will be able to see evidence of the errosion of the rock that they have made over time and are still doing today. Global warming notwithstanding, another ice age is a certainty at some stage in our future.
Norway is a beautiful country and well worth a visit if the majesty of nature is what you like to find in a vacation location. (If it's Mickey Mouse and Burger King you are seeking, you’ll be sorely disappointed!) The fjords of Norway, its mountains, and the people, make for an unforgettable (although it can be expensive) experience, leaving you wanting to return again in the near future.