Patent ID: 7319332

Claim:
A method of determining the formation factor of an underground zone from drill cuttings taken to the wellbore surface, wherein a device including a cell suited to contain cuttings and provided with electrodes connected to a device for measuring the conductivity of the cell content is used, the method comprising at least the following stages: cleaning said cuttings before setting them in the cell, filling the cell with a first electrolyte solution of known conductivity (σ A ) so as to saturate the cuttings with this first electrolyte solution, measuring the global electrical conductivity (σ* A ) of the cell with the content thereof, discharging the first electrolyte solution remaining between the cuttings from the cell, filling the cell with a second electrolyte solution of known conductivity (σ B ), determining the global electrical conductivity (σ* B ) of the cell containing second electrolyte solution and the cuttings saturated with first electrolyte solution, deducing therefrom the cuttings formation factor from the previous conductivity measurements and known conductivities of the first and second electrolyte solutions.