Sonography

The art of soundscape notation. It may include customary methods of notation such as the sonogram or sound level recording, but beyond these, it will also seek to register the geographic distribution of sound events (see this). Various techniques of aerial sonography are employed, for instance, the Isobel Contour Map. 

(Source: Schafer, R. Murray: Our Sonic Environment and the soundscape: the tuning of the world. Destiny Books 1994).