Oil-water distribution recognition method based on well-ground potential method

Abstract

The invention discloses an oil-water distribution recognition method based on a well-ground potential method. The oil-water distribution recognition method comprises the following steps: firstly, establishing an oil-water two-phase seepage equation; based on a potential and water saturation model, coupling the seepage equation with a potential differential equation to form a well-ground potential model; adopting a finite difference method and solving the pressure of the model by adopting an implicit expression and solving the saturation degree of the model by adopting an explicit expression; establishing a difference potential differential equation by utilizing a relation between the water saturation and conductivity, and solving the potential by adopting the implicit expression; establishing a computer solving model on the basis; carrying out analog computation on a one-dimensional water displacement oil process; simulating the whole water displacement oil process through numerical solution to obtain a correlational relation between potential distribution and resistivity of an underground target layer; after solving the resistivity of the target layer, inversing the water saturation of a reservoir stratum by utilizing an Archie equation. The method can be used for quantitatively describing the water saturation and oil saturation in the reservoir stratum by utilizing the potential determined on the ground, and oil-water distribution can be more rapidly and accurately recognized.

Description

technical field [0001] The invention belongs to the technical field of potential tapping of remaining oil in reservoirs, and in particular relates to an oil-water distribution identification method based on a well-ground potential method. Background technique [0002] At present, the research on remaining oil at home and abroad can be divided into three major items: the research on the distribution of macroscopic remaining oil, the research on the distribution of microscopic remaining oil and the research on the saturation of remaining oil. The first two are qualitative descriptions of remaining oil distribution, while the study of saturation is aimed at the quantitative characterization of remaining oil. [0003] 1. Research on macroscopic distribution of residual oil [0004] This part is to study the distribution of remaining oil on macro, large and small scales. [0005] (1) Calculation of oil displacement efficiency and sweep coefficient [0006] Generally, research ...

AI Technical Summary

Problems solved by technology

For example, people think that there is too much difference between the indoor physical simulation and the actual oil field; although the inspection well is real, it is only a glimpse; although the geophysical method has a wide range of applications, the measured saturation only reflects the remaining oil distribution around the wellbore; the production well test Restricted by instrument application conditions and accuracy; some reservoir engineering methods often have a strong empirical color; although the artificial neural network method is more accurate, it requires too much data, and its use is regional and local ; Reservoir numerical simulation is perfect from the perspective of the model itself, but there is no reliable geological model in the application, and so on

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