Here is a new company that I have found that uses geophysics. I believe their drill hole into their chargeability anomaly was successful. The black lines going perpendicular to the hole, are mineralization grades in the bottom photo. The longer the black lines slightly horizontal in the pic, the higher the grade. This is mostly a copper intercept with accompanying low grade gold values.The accuracy of their geophysics is quite impressive, showing them hitting mineralization upon entering the geophysical signature.

Also is important, is the top picture, where it shows the black line, (the drill hole) from a birds eye view, and how the bottom portion of that hole exited their anomaly. Then, when you look at the side view, you see that there is no mineralization on the bottom of the hole because of this. This shows the accuracy at the bottom of mineralization as well, meaning that the equipment used to define this anomaly is also very accurate in defining the bottom of deposits. Whereas this is clearly portrayed in this diagram, it may suggest why Quantec said on their website that they can calculate volume from the readings in some deposits and I believe that, because this technology has been around for over 40 years and it should be pretty accurate by now?

http://www.coloradoresources.com/i/maps/nrok/20130426_NorthRok_Chargeability_Xsection_6408600.jpg