Basically, they send probes down the holes to measure magnetic fields, force and direction along with electrical conductivity measurements. With this info, they will be able to determine which way the ore body is situated. A perfect example is Noront last year. They drilled holes 1&2, hit a bit, then did step out holes to the north which hit nothing. They then turned south, drilled again and hit hole #5, and the rest is history. If NOT had done downhole geophysics, hole #5 would of been hole #3. they would of saved drilling those 2 holes for nothing. FNC is being frugal here, making sure they get the best results out of those 1500m of drilling.

Cheers,

Glorieux