Formation analysis incorporating identification of immovable and viscous hydrocarbons

A method of analyzing a formation traversed by a wellbore, the formation including a flushed zone and a noninvaded zone, the method comprising:

• determining total porosity and permittivity of the noninvaded zone for an interval of the formation using data obtained from at least one logging device comprising one or more of a resistivity tool, a dielectric tool, and a logging tool run in the wellbore;
• generating a saturation model of the interval of the formation using the data obtained from the at least one logging device run in the wellbore, the saturation model including water saturation of the flushed zone for the interval of the formation and water saturation of the noninvaded zone for the interval of the formation;
• comparing the water saturation of the flushed zone for the interval of the formation and the water saturation of the noninvaded zone for the interval of the formation as provided by the saturation model, wherein comparing, when using a water-based drilling fluid, comprises:
• comparing whether the water saturation of the flushed zone is greater than the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than 1;
• comparing whether the water saturation of the flushed zone is equal to the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than 1;
• and
• comparing whether the water saturation of the flushed zone is equal to the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value equal to 1;
• wherein comparing, when using an oil-based drilling fluid, comprises:
• comparing whether the water saturation of the flushed zone is greater than the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than 1;
• comparing whether the water saturation of the flushed zone is less than the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than 1;
• comparing whether the water saturation of the flushed zone is equal to the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than 1;
• and
• comparing whether the water saturation of the flushed zone is less than the water saturation of the noninvaded zone when the water saturation of the noninvaded zone has a value of less than or equal to 1;
• and
• determining that the interval of the formation contains movable hydrocarbon, immobile or highly viscous hydrocarbon, or movable formation water based on results of said comparing for use in reservoir analysis.