Meaning of, in simple terms......
Downhole Crone Work.......Probes are used down the drilled hole and readings of the surrounding rock are taken, can be done at great depths.
Cutting Disks.......They are used with small Rock Saws, similiar to tile cutting saws. The blades (cutting disks) are diamond embedded and are for cutting the drill core in half. One have is kept and the other is sent for assay.
.......RL