192 1. No. II. 



THE STRAXDFLAT AND ISOSTASY. 



;oast of Prince Charles Foreland. Spitsbergen [from Nansen, 1920] 



mann, 1919]. It is conceivable that, where the cirque-glaciers are suf- 

 ficiently thick, they may be submerged to some extent, but. as a rule, 

 they will not descend much below sea-level. 



It is obvious that, in the manner described above, the local erosion 

 of small cirque-glaciers and accumulations of snow on the mountain sides 

 along the shores, may help to form low coastal borders, backed by over- 

 steepened mountain walls, as demonstrated by Fig. 8. 



I have observed in Spitsbergen that several cirque-glaciers, after 

 having eroded themselves down nearly to sea-level, may be widened bv 

 horizontal erosion, until they meet and their glaciers unite and form one 

 continuous, nearly horizontal ice-sheet, covering a fairly flat shore land 

 in front, with a mountain wall ascending steeply behind. Figs. 9 and 10 

 illustrate some glaciers of this kind, covering the low shore land along the 

 east coast of Prince Charles Foreland. Spitsbergen. 



In the same manner as a cirque-glacier, the flat shore glaciers may have 

 an ability to eat themselves backwards into the mountain side, by the frost 

 erosion along their inner edge. The remaining ridges between the original 

 cirques may thus gradually disappear, and few traces of them may be left. 

 As the flat glacier, by the pressure of the snow, each year accumulating on 

 its surface, will be moved slowly towards the sea, it may gradually carry 

 away the débris. 



In this manner we might imagine that a kind of strandfiat, with an 

 abruptly ascending, oversteepened mountain acclivity behind, can be 

 formed. But the plain thus arising cannot be expected ever to become 

 very broad, nor very level and regular, and there are in fact no indications 

 that the strandfiat of Norway, has to any appreciable extent been formed 

 in this manner. In southern Norway there are very few traces of cirques 

 having ever been formed near present sea-level; though this does not prove 

 that it may not have been the case during the Great Ice Age. 



Any how, it cannot be doubtful that, in regions with the necessary 

 climatic conditions, as it now is in Spitsbergen, the above mentioned form 

 of glacial erosion may have been of importance for the development of a 

 low shore land, although it has not been able to form a typical strandfiat. 



