Method for Determining The Relative Content of A First Rock Species and of A Second Rock Species in A Rock Sample Extracted From A Wellbore, and Associated Device

A device for determining the relative content of a first rock species and of a second rock species in a rock sample extracted from a wellbore, the device comprising:

• an enclosure able to receive the rock sample and a reactant, the reactant reacting simultaneously with the first rock species and with the second rock species to produce a compound, the rate of reaction of the reactant with the first rock species being faster that the rate of reaction of the reactant with the second rock species;
• a means for measuring a first information (PT1) relative to a first cumulative amount of compound produced at a first instant (T1) and for measuring a second information (PT2) relative to a second amount of compound produced at a second instant (T2) subsequent to the first instant (T1);
• a means for calculating the relative content of the first species in the rock sample at least from the first information determined at the first instant (T1);
• a means for calculating the relative content of the second species in the rock sample at least from the second information determined at the second instant;
• wherein the device comprises:
• a means for determining a corrected amount (Cv) of compound generated by the reaction of the second species with the reactant at the first instant (T1);
• and
• a means for calculating the relative content of the first species in the rock sample and the relative content of the second species in the rock sample based on the corrected amount (Cv).