METHOD FOR DETERMINATION OF OIL-FILLED FORMATIONS Russian patent published in 2013 - IPC E21B47/00 E21B49/00 G01V11/00 

FIELD: oil and gas industry.

SUBSTANCE: bore core is selected and examined, induction logging and induced gamma-ray logging or neutron-neutron logging is made and log curves are analysed for the roof of production tier. At that formations with apparent resistivity are identified with values less than 6-8 Ohm/m during induction logging and against values at curves of induced gamma-ray logging or neutron-neutron logging making less 85% and less than values of lower formations. Among these formations it is necessary to select strata without loamy lintels and strata of carbonate oil-filled formations and values of apparent resistivity not less than 15 Ohm/m against data of induction logging. Then sedimentary types for the selected formations is defined and if oil-saturated sandstone is present then conclusion is made about terrigenous origin of these formations. Then values are specified for porosity coefficient, permeability and oil-saturation coefficients and when lower limits for this region are exceeded the indentified formations will be referred to productive formations.

EFFECT: increase of operational efficiency during installation of the bottom-hole complex, improvement of level of detail and authenticity of GIS data for identification of geological rating for rock masses.

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