THE PHYSICAL HISTOEY OF THE NORWEGIAN FJORDS. 14o 



is found where tlie side descends abruptly from the 200 

 fathom isobathic line. That Scandinavia and the North 

 Sea partook of these great oscillations of the land is 

 miquestionable. It is inconceivable that any portion of 

 Western or Northern Em-ope could have remained approxi- 

 mately unmoved while the adjoining regions were undergoing 

 such stupendous changes of level, and we are thus in a 

 position to account for the great depth of the fjords even 

 alloAving for the effect of glacier-erosion over their floors. 

 The fjords when river-valleys may be inferred to have 

 entered the Korth Sea with channels of perhaps 2,000 

 feet or more, and to have crossed the floor of that 

 sea in the direction of the Arctic Ocean, which descends very 

 rapidly to a depth of over 1,000 fathoms; by this means, 

 alone could the rivers have been drained. But, as already 

 stated, these channels are not now discoverable, to any 

 important extent, by the soundings ; which fact I have 

 endeavoured to account for by supposing that they have been 

 tilled up with glacial mud, sand, gravel, and boulders 

 carried down by floating ice from the interior highlands, and 

 spread over the floor of the Continental (now the North Sea) 

 Platform by the tides and currents. Similar silting of the 

 original channels has taken place olf the coast of Western 

 Europe and the British Isles as I have shown Avlien dealing 

 with the sub-oceanic river-valleys of this region ; but it may 

 well be supposed that the effects would be even greater in 

 the case of the North Sea wdiich Avashes the coast of Norway 

 and received the glaciers and icebergs which descended 

 from its mountains. We may now conclude this necessarily 

 brief account of these physical events by arranging them 

 under the following stages : — 



3. General succession of events in the Idstory of tJie Norioegian 



fjords. 



(a) Earliest stage (Pre-Silurian.) Continental conditions ; 

 land formed of Archa3an rocks. Erosion of river- 

 valleys commences. 



{b) Second stage. Partial submergence during Silurian 

 times. 



(c) Third stage. Elevation of land during later 

 Pala3ozoic, Mesozoic and Tertiary times ; with con- 

 tinuous erosion of river-valleys. 



{d) Fourth stage. (Glacial period.) Great upheaval of 

 land and sea-areas accompanied by valley erosion. 



