Tool and method for determining formation parameter

A method of characterizing a subterranean formation including the steps of having in a section of a well penetrating the rock formation, a sensing device that generates a sensing field within a measuring volume of the rock formation;

• a flow generating device that causes a flow through the measuring volume by injecting fluids into the formation, and sensors responsive to changes in the sensing field, wherein sensor responses are indicative of an amount of constituent fluid phases in the measuring volume under at least two different flow conditions in the formation and further comprising the step of determining parameters indicative of a fractional flow state and saturations in the volume being in the fractional flow state.

A method of characterizing a subterranean formation including the steps of having in a section of a well penetrating the rock formation, a sensing device that generates a sensing field within a measuring volume of the rock formation;

• a flow generating device that causes a flow through the measuring volume by injecting fluids into the formation, and sensors responsive to changes in the sensing field, wherein sensor responses are indicative of an amount of constituent fluid phases in the measuring volume under at least two different flow conditions in the formation and further comprising the step of fractioning the amount of constituent fluid according to a parameter indicative of the composition of the constituent fluid and determining shifts in the fractioning between the at least two different flow conditions.