Method for calculating oil saturation of reservoir by using formation test data of MDT cable

Abstract

The invention provides a method for calculating oil saturation of a reservoir by using formation test data of an MDT cable, which comprises the following steps of: collecting data of effective porosity phi and shale content Vsh of the reservoir meeting standards, and calculating irreducible water saturation Swb of the reservoir; when the reservoir is subjected to MDT cable formation testing, when pumped fluid does not contain slurry filtrate and the water content of the pumped fluid tends to be stable, the pumped fluid can be used as the water production rate FW of the pumped reservoir; when the pumped fluid does not contain the slurry filtrate, the oil viscosity [mu] o and the water viscosity [mu] w analyzed by the pumped fluid can be used as the oil viscosity [mu] o and the water viscosity [mu] w of the pumped reservoir under the formation condition; a reservoir water saturation SW calculation formula is established according to a Darcy law equation of the oil flow velocity and the water flow velocity in combination with a Jones equation of the oil and water relative permeability, and the reservoir water saturation SW can be calculated; and calculating the oil saturation SO of the reservoir. And analyzing the pumped fluid to obtain the water content and oil viscosity of the pumped liquid, and combining the water viscosity with the porosity and shale content of the reservoir to obtain the oil saturation of the reservoir.

Description

technical field [0001] The invention relates to the technical field of geophysical exploration and development, in particular to a method for calculating the oil saturation of a reservoir by using MDT cable formation test data. Background technique [0002] In the process of oilfield exploration and development, the study of reservoir oil saturation is very important. The commonly used methods are mainly experimental method, well logging method (Archie formula method) and reservoir numerical simulation method. The experimental method is mainly based on the oil saturation test and research based on the reservoir core obtained during drilling to obtain the oil saturation, which is costly and takes a long time to test. If the core is broken or seriously polluted, the error of the experimental result will be large. Well logging is Archie's formula method. This method is mainly studied based on the petrophysical volume model. If the lithology and physical properties of the reser...

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Problems solved by technology

[0003] The present invention overcomes the deficiencies in the prior art. The existing calculation method has the problems of high cost, long experiment time and large calculation result error, and provides a method for calculating reservoir oil saturation by using MDT cable formation test data method, during the MDT cable formation test, the pumped fluid analysis can obtain the water content, oil viscosity, water viscosity and other data of the pumped liquid, and combined with the reservoir porosity, mud content and other physical properties data, the reservoir properties Oil saturation will have important guiding significance for calculating reserves, evaluating production value, and compiling development plans, etc.

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