Comment by gtvwill

Worked on a core drill rig that that did 2200m core drilling, worked a number of holes from 100-2200m on a few different types of surface rigs. Stuff gets weird when you get deep >1500m. Runs take ages, bit changes can take an entire shift. The structures in the rock can come out looking like a picture in space (black base littered with color). Hitting 10 miles (16km) would be epic. Something like 100 ton rod string hanging at BQ size. Insane.