Geologists are 'scientists' with an unnatural obsession with geology (rocks and alcohol). Often too intelligent to do monotonous sciences like biology, chemistry, or physics, geologists devote their time to mud-worrying, volcano poking, fault finding, bouldering, dust-collecting, and high-risk colouring.
One of the main difficulties in communicating with geologists is their belief that a million years is a short amount of time and their heads are harder than rocks. Consequently, such abstract concepts as "Tuesday Morning" and Lunchtime are completely beyond their comprehension. (This difficulty generates problems particularly when dealing with the girlfriend/boyfriend/spouse and attempting to explain why you were "gone for so long" or why something is taking "so long to occur.")