escarpment vs jebel

escarpment

noun
  • A steep descent or declivity; steep face or edge of a ridge; ground about a fortified place, cut away nearly vertically to prevent hostile approach. 

jebel

noun
  • A hill, a mountain (especially in the Middle East or North Africa). 

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