Improved Saturation Determination with the EPT in Western Canada’s Vugular Dolomitic Carbonates


Raoul Leitham



Variations in texture, vugular porosity, and the extremely complex internal geometry of Canada’s dolomitic carbonates pose problems for state-of-the-art electric log analysis models. Numerous laboratory experiments on rock samples indicate that Archie’s cementation exponent "m", can vary significantly over short intervals, but because it is impossible to measure this parameter in-situ directly, assumed average values are used in water saturation (S,, and S..) calculations. This rigid approxi- mation technique can, however, compute grossly erroneous water saturation values.