i6 



IKIDIJOF NANSEN. 



M.-.\. Kl. 



III. THE EFFECT OF THE SUBAËRIAL DENUDATION 

 IN THE COASTAL ZONE. 



If a land-surface sloping- f^Tarlually towards the coast, be exposed to 

 subaërial deniulation duriniL,^ sufficiently long periods, and witliout being- 

 disturbed by other processes, it is obvious that a base-levelled plain may 

 finally be developed along the coast, and according- as the sloping land- 

 surface is denuded, this plain will extend landwards. Fig. 4 demonstrates 

 very roughly the development. S L is sea-level and gab the initial land 

 slope, which by subaërial denudation is lowered to c d, and then to e f, 

 and the base-levelled plain a c c is thus developed. It is here supposed 

 that the rate of suliaërial denudation as well as the resistance of the rocks 

 have been the same in all regions of the land slope, which of course is, 

 not the case, as a rule. The transition between the land slope and the 

 base-levelled plain would naturally be very gradual, and there would not 

 be a sharp break as in the figure. 



d 



Figs. 4 and 5. 



