physiography vs topography

physiography

noun
  • The subfield of geography that studies physical patterns and processes of the Earth. It aims to understand the forces that produce and change rocks, oceans, weather, and global flora and fauna patterns. 

  • The descriptive part of a natural science as distinguished from the explanatory or theoretical part. 

topography

noun
  • The features themselves; terrain. 

  • A detailed graphic representation of the surface features of a place or object. 

  • The surveying of the features. 

  • A figurative landscape; a structure of interrelated ideas, etc. 

  • A precise description of a place. 

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