

Figure 79 — Shelf ice. The rift in the foreground is a frozen lead created after the 

 parting of the shelf ice. The dark spots on the ice are seals. The undulations in the 

 background were caused by compression of the ice. 



Figure 80 — Cliff of shelf ice. Each strongly marked horizontal band represents a 

 year's snowfall. (Mawson. ) 



70 



