#geological_phenomenon  a natural phenomenon involving the structure or composition of the earth
  subtype:  earthquake  alluvial_fan  cataclysm  continental_drift  sedimentation  inundation  frost_heave  volcanism
  supertype:  natural_phenomenon__naturalphenomenon  all non-artificial phenomena
     supertype:  phenomenon  any state or process known through the senses rather than by intuition or reasoning
        supertype:  process__proces__physicalsituation  intuitively, the class of things that happen and have temporal parts or stages; examples include extended events like a football match or a race, actions like pursuing and reading, and biological processes; sumo#process is not identical to pm#situation because an instance of pm#situation is not necessarily an instance of sumo#physical
           supertype:  situation  something that "occurs" in a real/imaginary region of time and space
              supertype:  thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
           supertype:  process_or_process_description
              supertype:  processing_thing
                 supertype:  thing_playing_some_role  category to classify things according to roles/viewpoints; classification under this category is application-dependant
                    supertype:  thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
           supertype:  physical__physical_thing  an entity that has a location in space-time; locations are themselves understood to have a location in space-time; click here for more details on the identical category sowa#physical_thing
              supertype:  thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type

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