Method for determining near critical reservoir test meter oil recovery index

Abstract

The invention relates to a method for determining an oil reservoir test meter oil production index. The method comprises the following steps of A, regressing the stable flowing bottomhole pressure andthe test yield under each working system to obtain a relational expression of the flowing bottomhole pressure and the test yield; B, obtaining the original formation pressure according to the relational expression of the flowing bottomhole pressure and the test yield, and obtaining the test pressure difference under each working system; C, based on the relation between the flowing bottomhole pressure and the time in the testing period, obtaining the testing thickness through an elastic two-phase method; and D, correcting the original formation pressure, and calculating to obtain the test thickness so as to obtain the test meter oil production index. According to the method, the original formation pressure is corrected, and the test thickness is obtained by adopting an elastic two-phase method, so that the accurate test meter oil production index is obtained.

Description

technical field [0001] The invention relates to the technical field of oil reservoir exploitation, in particular to a method for determining the oil recovery index of a near-critical oil reservoir test meter. Background technique [0002] During the testing process of the oil wells in the low-permeability fractured near-critical reservoirs of buried hills, when the bottom hole flow pressure is far lower than the bubble point pressure, the test gas-oil ratio is basically unchanged, which reflects that the gas-oil ratio is basically unchanged during the near-critical fluid production process. changing characteristics. However, based on the test production and test bottomhole flow pressure data under different working systems, the current common method for calculating the oil recovery index per meter is to directly divide the test production by the test pressure difference and test thickness, and calculate the test meters under different working systems. The oil recovery index...

AI Technical Summary

Problems solved by technology

However, based on the test production and test bottomhole flow pressure data under different working systems, the current common method for calculating the oil recovery index per meter is to directly divide the test production by the test pressure difference and test thickness, and calculate the test meters under different working systems. The oil recovery index is quite different

The reason is: the original formation pressure value is not measured or is inaccurate, resulting in inaccurate production pressure difference; in addition, the test thickness of the conventional method is directly taken from the perforation thickness or directly read from the logging curve

In order to accurately determine the oil recovery index per meter of fractured near-critical oil reservoirs in buried hills, it is necessary to correct the original formation pressure by a certain method, and calculate the test thickness through the test data, so as to obtain a reasonable oil recovery index per meter, but it has not been found before Related Research Reports

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