Carbonate reservoir based permeability representing method

Abstract

The invention discloses a carbonate reservoir based permeability representing method. According to the carbonate reservoir based permeability representing method, pore throat radius aperture line which can be represented by both absorption method and high pressure mercury penetration method is determined, absorption method is adopted to measure the aperture structure below the aperture line, and high pressure mercury penetration method is adopted to obtain the aperture structure above the aperture line for splicing, so that carbonate reservoir pore structure characteristics are obtained; unitpressure mercury penetration saturation degree and the permeability of different samples are obtained, and the function relationship of the largest unit pressure mercury penetration saturation degreeand the permeability is established. The carbonate reservoir based permeability representing method can be used for representing whole pore segment pore structure characteristics, and improving latertest results accuracy. The largest unit pressure mercury penetration saturation degree is adopted in accurate calculation of carbonate reservoir permeability, a large amount of other rock core experiments are avoided, carbonate reservoir permeability quantitative evaluation result accuracy is ensured, and at the same time, the carbonate reservoir based permeability representing method is simple and practical, is capable of reducing cost effectively, and is high in economical practicality.

Description

technical field [0001] The invention relates to a quantitative characterization method of reservoir permeability, in particular to a characterization method based on the permeability of carbonate rock reservoir. Background technique [0002] In carbonate reservoirs, the complexity of rock pore structure results in strong heterogeneity of the reservoir, resulting in no high-precision functional relationship between porosity and permeability. The micro-nano pore structure parameters of shale reservoirs are usually measured by the adsorption method and the high-pressure mercury injection method, but the main problem in the measurement is that the measurement ranges of different methods are different, and neither the adsorption method nor the high-pressure mercury injection method can be comprehensive. Characterize the pore structure characteristics of micro-nano pores in shale reservoirs. Therefore, it is not feasible to calculate the permeability of complex carbonate reservoi...

AI Technical Summary

Problems solved by technology

The micro-nano pore structure parameters of shale reservoirs are usually measured by the adsorption method and the high-pressure mercury injection method, but the main problem in the measurement is that the measurement ranges of different methods are different, and neither the adsorption method nor the high-pressure mercury injection method can be comprehensive. Pore ​​Structure Characterization of Micro-Nano Porosity in Shale Reservoirs

Therefore, it is not feasible to calculate the permeability of complex carbonate reservoirs by using the permeability calculation formula established from porosity.

In addition, since the empirical constants in the free fluid model and the average model are difficult to determine accurately, it is also difficult to accurately calculate the permeability of complex carbonate reservoirs