224 FRIDTJOF NANSEN. M.-N. Kl. 



sidence was not unifonn, it Ix-iii^' ^^rcatcr iiilaml than iicar<-r ilie coast, 

 and in \]]v outer ccjastal rej^'icjn thcrf nia\ jirobably have been an upheaval 

 uf the land flurinj^'' the first part of the suhsirlcnce of the inner land. 



Hence it is not prohahic that tlie strand flat was developed to any 

 larj^e extent during this pcriot] wlicii the laiul surface was warped, a 

 characteristic feature of the strandfiat heinj^- that its levels are practically 

 horizontal. 



Howe\'er this may be, it seems i)rol)al)le tliat tlie j^eneral sea-level 

 has sunk somewhat since the strandfiat beji^an to he devehjped, and it is 

 possible that changes in the thickness and extent of existing ice-caps may 

 at least to a large extent have caused these changes in the sea-level. 



As long as there are ice-caps which during some periods increase 

 and during others decrease, the average depth of the Ocean and the general 

 sea-level will not remain c|uite stable. 



It might then be |)ossil)le that the jMX'sent submerged strandfiat was 

 planed during some long period when the ice-caps of the earth were a 

 good deal greater than now, and that although there has been an isostatic 

 upheaval of the land since that time, the level of this lowest part of the 

 strandfiat has not been raised above the present level of the sea surface. 



As will be mentioned in the next chapter there is, however, weighty 

 evidence to show that the lower level of the emerged strandfiat was formed 

 just before the last glacial period. If therefore the plane of the submerged 

 strandfiat represents a different stage, we would in that case have to 

 assume that it was formed before the lower level of the emerged strand- 

 flat, although this would be somewhat difficult to understand. 



By the assumption that, during the long time which has elapsed since 

 the strandfiat began to be formed, the shore-line has been shifted partly 

 l)y isostatic upheaval of the land and partly l)v changes in the general level 

 of the sea, we obtain a simple explanation of the reason for there not 

 being greater differences in the heights of the strandfiat in the divers 

 regions. 



The explanation of the fact that the lower level of the emerged 

 strandfiat seems to stand somewhat lower along the coast of Helgeland 

 and in the inner part of Sogne Fjord than along the outer west coast of 

 southern Norway, in the region of Sogne Fjord and south of it. may 

 then be, either that a smaller quantity of rock have been removed from 

 the land surface in these regions after the formation of this level, — or 

 that the isostatic upheaval of the land has not yet been quite completed 

 in these regions. 



The former explanation seems hardly probable, considering that the 

 rocks of Helgeland are not on the whole very resistant. It seems less 

 improbable that the upheaval of the land after the last glacial period is 

 not yet finished in these regions which were considerably depressed 

 during the last glacial epoch. The inner region of Sogne Fjord was de- 



