Source : Webster's Revised Unabridged Dictionary (1913)

Geologize \Ge*ol"o*gize\, v. i. [imp. & p. p. {Geologized}; p.
   pr. & vb. n. {Geologizing}.]
   To study geology or make geological investigations in the
   field; to discourse as a geologist.

         During midsummer geologized a little in Shropshire.
                                                  --Darwin.