METHOD FOR DETERMINATION OF OIL-SATURATED FORMATIONS Russian patent published in 2014 - IPC G01V11/00 E21B49/00 E21B47/00 

FIELD: oil and gas industry.

SUBSTANCE: bore core is selected in the well and surveyed, the oil saturation factor is determined for the bore core, an integrated well log survey is performed and the oil saturation factor is determined according to the survey results, a relative factor is determined as a ratio of the core oil saturation factor to the oil saturation factor of the well log survey, log curves for wells are analysed in the terrigenous section of the productive formation, reservoir beds are identified with induction logging apparent resistivity less than 3 Ohm/m, among the identified reservoir beds the beds are selected with the mineral composition of the core and mud having minerals reducing specific resistivity and high content of current-carrying elements against the log survey data, the true oil saturation factor is determined for the identified beds by multiplying the oil saturation factor of the well log survey by the relative factor and the obtained result is compared with oil saturation factor values for low oil-saturated and oil-saturated reservoir beds and the respective bed is referred to the low oil-saturated and the oil-saturated reservoir beds.

EFFECT: improving accuracy of the oil-saturated bed in the well log.

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