Here is but a portion of the proof ,understanding and interpretation. I would suggest not to confine ones self to resonating with one opinion/documentation only, and I find it best to consult as many sources as possible and derive a thesis from ALL data by keeping an open mind. This will take many hours to construct a knowledge that will enable one to discern the rate of probabilities/possibilities that is best applied to this situation.

The SLI Technical report section that contains Quantecs explanation of how geophysics works and the processes of elimination they arrived at during determination of the consistency of the chargeability/resitivity anomalies.

http://crustal.usgs.gov/geophysics/software.html

http://www.quantecgeoscience.com/

http://www.eos.ubc.ca/ubcgif/iag/foundations/properties/resistivity.htm

http://cseg.ca/members/cseg-history-1960-1969