Archie mode method for confirming initial oil saturation of oil layer

Abstract

The invention relates to an Archie mode method for determining oil layer initial oil saturation, comprising the following steps: (1) inspecting the structure of oil pool and the geological condition of a reservoir bed, and collecting relevant sampling data; (2) correcting initial oil saturation and initial water saturation data; (3) calculating the average value of the initial oil saturation or the initial water saturation according to a downhole single sand layer, namely, a substratum; (4) calculating the average value of average degree of porosity according to the single sand layer, namely, the substratum, and reading the corresponding stratum deep direction-finding resistivity data by well logging curve; (5) collecting the data and drawing; (6) establishing the Archie mode of different reservoir bed types for a single layer with approximate reservoir bed deposition and oil pool and reservoir formation characteristics; and (7) calculating the initial oil saturation for the unsampled oil layer requiring the calculation of the initial oil saturation by using the Archie saturation formula. The initial oil saturation calculated by applying the method has high precision.

Description

Technical field: [0001] The invention relates to the field of petroleum exploration and development of oil layers and a method for calculating petroleum geological reserves, in particular to an Archie model method for determining the original oil saturation of oil layers. Background technique: [0002] In rock pores, the percentage of oil volume in the effective pore volume is called oil saturation, and the percentage of oil volume in the reservoir in the original state is called the original oil saturation. Since the original oil saturation of the oil layer is an important parameter to evaluate the oil layer and calculate the geological reserves of the reservoir, it has always been valued by the petroleum geological circles at home and abroad, and the measurement method is also constantly developing. [0003] The first is to use oil-based mud coring to directly measure the original water saturation. Oil-based mud coring has been carried out in Europe, America and the former...

AI Technical Summary

Problems solved by technology

In the exploration stage of lithologic oil and gas reservoirs, the number of oil-based mud or sealed core wells is limited, and lithological factors make the original oil saturation and porosity of the oil layer not completely positively correlated, making the application of the measured original oil saturation limited. limit

In the past, when using Archie's formula to calculate the original oil saturation of a reservoir, an Archie constant was generally used in a large area: the porosity index m, the saturation index n and the lithology coefficient a Archie parameter. The accuracy of the original oil saturation calculated in this way is relatively low. Low

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