bas-relief vs prominence

bas-relief

noun
  • A low or mostly-flat sculpture which is carved into a wall, or is in the form of a tile mounted flat to a wall, rather than a fully three-dimensional, free-standing figure. 

adj
  • Refers to any aspect of sculpture which is flat or in the bas relief style. 

prominence

noun
  • A bulge: something that bulges out or is protuberant or projects from a form. 

  • The state of being prominent: widely known or eminent. 

  • Autonomous height; relative height or prime factor; a concept used in the categorization of hills and mountains. 

  • A gaseous projection, often loop-shaped, springing from the surface of the Sun or a star. 

  • Relative importance. 

How often have the words bas-relief and prominence occurred in a corpus of books? (source: Google Ngram Viewer )