URI
Notation
55
Caption
Earth Sciences. Geological sciences
Examples
55(1) Regional geology (in general)
Broader class
5  MATHEMATICS. NATURAL SCIENCES
Narrower classes
550Ancillary sciences of geology etc.
551General geology. Meteorology. Climatology. Historical geology. Stratigraphy. Palaeogeography
552Petrology. Petrography
553Economic geology. Mineral deposits
556Hydrosphere. Water in general. Hydrology