Residual oil distribution rule quantitative analysis method

Abstract

The invention discloses a residual oil distribution rule quantitative analysis method, which comprises the following steps of: step 1, establishing a grid system, and simulating a well and an artificial crack by using a local grid encryption technology; step 2, inputting basic parameters such as porosity, permeability, original saturation and the like, determining the size of a water body, and selecting a relative permeability curve; step 3, carrying out sensitivity quantitative analysis on the parameters, and carrying out optimal design on a digital-analog scheme by using a method related toan orthogonal test; and step 4, taking oil field production dynamic data as a basis of historical fitting, and carrying out comprehensive inspection on the established model. According to the residualoil distribution law quantitative analysis method, orthogonal test design is introduced, the factor combination and quantity of a digital-analog scheme are determined, the distribution law of underground oil, gas and water is reflected more accurately through historical fitting, a large amount of manpower, material resources and time are saved, and the method has the characteristic of high applicability and is suitable for popularization and application.

Description

technical field [0001] The invention belongs to the technical field of oilfield development, and in particular relates to a method for quantitatively analyzing remaining oil distribution rules. Background technique [0002] Residual oil refers to the oil that has not yet been produced in oil layers, reservoirs or oil fields that have been put into development. The main task in the later stage of development is to carry out refined, quantitative, dynamic and predictive reservoir description with the remaining oil saturation as the main content. [0003] my country is the country with the highest proportion of oilfields developed by water injection in the world. Most oilfields have entered the stage of high water-cut oil production in the middle and late stage of development. Moreover, the geological conditions of my country's oilfields are complex, the properties of crude oil are greatly different, and the reservoir heterogeneity is serious. There are still 60% to 70% of un...

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Problems solved by technology

On the one hand, it is becoming more and more difficult to add reserves, and the degree of exploration is high. The scale of newly discovered oilfields is generally decreasing, and the proportion of low-permeability and heavy oil reserves in the newly-added proven reserves is increasing year by year, and the quality of the reserves is deteriorating. On the other hand, the development contradiction of "three highs and two lows" in my country's water injection oilfields is prominent, that is, high comprehensive water content, high recovery degree, high oil recovery rate, low storage-production ratio, and recovery factor. Low, there is still a lot of oil that cannot be recovered

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