KklDlJOK NANSEN. M.-N. Kl. 



Tt: was cinpliatically Diaiiitaincd that a hroarl straiulflat, like that of 

 iiorllicrn Norway (Helg-claii'l i, cannot have been formed by wave erosion, 

 (luring- a rcasfjiiahle time, before the coast had been dissected by deep 

 fjords and channels, but it must have ])een formed after that time. This 

 was especially for two reasons: 



On tlie one side, the erosive effect of the waves on the shore would 

 be much reduced in the extremely shallow sea over a submerged, nearly 

 horizontal strandfiat, along- an undissected coast, where the waste would 

 have a difficult way to travel in order to reach deep water. While along 

 a dissected coast the line of attack of the marine denudation is immensely 

 increased, and the waste is easily washed into the deep channels and fjords. 

 The subaërial denudation is also much increased because on all islands 

 and peninsulas the waste has got a short way to travel to reach the sea. 



On the other side, the total quantity of rock that had to be worn 

 away from the small islands and peninsulas of a dissected coast, like the 

 present one, would be only a small fraction of the quantity that must 

 have been cut away from a high and solid coast. 



For the above reasons, I reached the conclusion that the Norwegian 

 strandfiat cannot be of preglaciale age, but must have been developed 

 especially before, during and after each glacial period when the rough 

 moist and cold climate highly favoured an active subaërial denudation, 

 as well as an active marine denudation. 



Although I shall later go more fully into this question, let me here 

 at once correct what I consider to be a mistake. The development of the 

 strandfiat cannot, as a rule, be assumed to continue during the late part 

 of a glacial period, when the glacial margin is retreating from the coast, 

 and not for a considerable period after that time, because, near the end 

 of a glacial period, the land along the greater part of our coast, has most 

 certainlv been depressed by the weight of the extensive ice-sheet, far 

 below any level of the strandfiat, and it took a long time before the land 

 had again returned to its natural level. 



Tet me in this connection also correct another mistake. It was as- 

 sumed that the slow oscillation of the shore-line during the glacial periods 

 may have been of importance for the formation of the strandfiat. These 

 oscillations w^ere "caused by the isostatic movements of the land under 

 the pressure of the ice-caps" as well as "by the accumulation of water in 

 the ice-caps by -which the volume of the ocean was altered; and also, 

 though slightly, as a result of the raising influence exerted on the sea- 

 level by the attraction of the ice-masses on land" [1904, p. 109]. 



A characteristic feature of the strandfiat is, however, the great width 

 and the nearly perfect horizontality of its levels, which indicate that it 

 must have been formed during several long periods, when the level of 

 the shore-line remained fairly stable. It has not been formed during 

 periods of isostatic movements of the land due to the load of the ice-caps, 



