ice field vs ice hole

ice field

noun
  • A large expanse of floating ice (several miles long). 

  • A network of interconnected glaciers or ice streams having a common source. 

ice hole

noun
  • A hole in the ice of a frozen body of water, often man-made with the scope of fishing. (This entry is a translation hub.) 

How often have the words ice field and ice hole occurred in a corpus of books? (source: Google Ngram Viewer )