Individual #volcanology__vulcanology  the branch of geology that studies volcanoes
  >part of:  #geophysics__geophysical_science  geology that uses physical principles to study properties of the earth
     >part of:  #geology  a science that deals with the history of the earth as recorded in rocks
        >part of:  #earth_science__earthscience  any of the sciences that deal with the earth or its parts

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