ascend vs upthrust

ascend

verb
  • To move upward, to fly, to soar. 

  • To slope in an upward direction. 

  • To become higher in pitch. 

  • To succeed. 

  • To trace, search or go backwards temporally (e.g., through records, genealogies, routes, etc.). 

  • To lose one's virginity, especially of a man through unpaid and consensual sexual intercourse with a woman. 

  • To go up. 

  • To rise; to become higher, more noble, etc. 

upthrust

verb
  • To be thrust upwards. 

  • To thrust something upwards. 

noun
  • Buoyancy. 

  • An upward movement of part of the Earth's crust. 

  • An upward thrust. 

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