28 FRIDTJOF NANSEN. M.-X. Kl. 



V. MARINE DENUDATION. SHORE EROSION 



BY FROST. 



There remains then no other process for the planing of the strandfiat 

 but the marine denudation. Most writers assume that this denudation is 

 chiefly due to \\ave erosion. But if the wave erosion has been able to 

 cut the plane of the broad and nearly horizontal strandfiat along the coast 

 of Norway, it must certainly have been able to cut similar planes, at least 

 to some extent, along more southern coasts, exposed to the full fury of 

 the ocean during sufficiently long periods, even though those coasts were 

 less dissected. But, as a rule, no real strandfiat occurs along the coasts 

 of milder regions. 



Considering the extremely slow progress of wave erosion alone on a 

 coast built up of solid rock, it is conceivable that during the very long time 

 wdixh the wave erosion will need for cutting a fairly broad strandfiat, the 

 land will be so much denuded and dissected by the atmospheric weathering 

 and fluvial erosion, and will be so much raised by the isostatic elevation 

 thus caused, that the traces of the strandfiat may be more or less ob- 

 literated. 



The striking fact is that the typical strandfiat is a characteristic 

 feature of high northern and southern latitudes. It occurs preeminently 

 in regions that have formerly been subjected to glacial conditions or have 

 at least had very cold climates, like the coast of Siberia. It seems, there- 

 fore, to be a natural conclusion that the formation of typical strandfiats 

 have, as a rule, had some connection with low temperatures. 



S. W. Gushing [1913] has described a remarkably smooth emerged 

 plane of marine denudation along the east coast of India, wh'ch is like a 

 strandfiat. It is backed by "an ancient sea wall," rising steeply to an 

 average height of over 650 metres above sea-level, in some regions even 

 to 2300 metres in an almost vertical wall. Numerous remnants of quartzite 

 rise in the shape of steep-sided ridges or stacks, often with flat summits, 

 above this plane. Their bases are not unfrequently marked by sea caves, 

 and there seems to be room for little doubt, but that this plane, in places 

 about 75 kilometres broad, is actually formed by wave-erosion [cf. D. W. 

 Johnson, 1919, p. 231]. The plane has been developed over meta 



