GV.. / ( V.I/. GKOLOGY OF NORTH GREENLAND 79 I 



nomena of the Greenland glaciers is the uijturning of the hori- 

 zontal layers at the ends and sides of glaciers. The upturning 

 is most conspicuous as a rule at the extreme end. It becomes 

 less and less striking with increasing distance from the end, and 

 is not apjxarent at any considerable distance above. At the 

 extreme ends of glaciers the upturning was seen to vary from 

 a few degrees to vcrticality. An upturning of 30° or 40° was 

 by no means uncommon. Higher inclinations were less fre- 

 quent, and in but a single situation, namely in a glacier on the 

 south of Olriks Bay (Figs. 20 and 21), was verticality attained. 

 Figs. 20 and 21 represent a vertical face of ice at the end of a 

 glacier, but the face is parallel to the axis of the glacier, not 

 transverse to it. The same phenomenon in the same relations 

 may frequently be seen at the sides of the glaciers. Fig. 22 

 shows the positions of the layers at the lateral margin 'of a 

 glacier near Karnah. The layers are turned up most conspicu- 

 ously at the extreme edges, and less and less markedly with 

 increasing distance from them. So closely is the upturning 

 confined to the lateral margins that the larger part of the sur- 

 face of a glacier, even one where the lateral upturning is 

 extreme, shows nothing of it. The upturning at the sides of 

 a glacier is rarely equal to that at the end. 



The lateral upturning is best seen at the vertical ends of 

 glaciers. The following diagram (Fig. 23) may almost be said 

 to represent the normal structure of a small glacier, as seen 

 from its vertical end. If the glacier be a large one the structure 

 shown is more likely to be that indicated diagrammatically in 

 Hg. 24. The number of anticlines and synclines seen in cross- 

 section in a large glacier may be several. 



The upturning of the ends and edges of la3'ers is not con- 

 fined to differentiated glaciers, but affects the edge of the ice- 

 cap as well. The edges of the main or local ice-caps were 

 crossed in all at nine points. In seven of the nine, the mar- 

 ginal upturning of the layers was markedly developed. Gen- 

 erally speaking, it was most conspicuous where the visible 

 amount of debris was greatest, and least where the debris was 



