Method for predicting vertical well volume fractured reservoir reform volume of low permeable reservoir

Abstract

The invention discloses a method for predicting vertical well volume fractured reservoir reform volume of low permeable reservoir. The method sequentially comprises the following steps: (1) calculating the induced stress produced by hydraulic fracture in a three-dimensional space; (2) calculating the formation pore pressure obtained after leak-off of fracturing fluid; (3) calculating the formation pore elastic stress obtained after the leak-off of the fracturing fluid; (4) overlapping the stress fields obtained in the step (1), (2) and (3) with an in-situ stress field to obtain a new crustal stress field, and calculating the magnitude and direction of three-way principal effective stress in the overlapped reservoir space; (5) calculating the open fracture determination coefficient M of a natural fracture in the reservoir space and the shear fracture region determination coefficient S of the natural fracture so as to predict the volume fractured reservoir reform volume. The method is used for predicting the reservoir reform volume after vertical well volume fracturing, is better in operability and accuracy, provides a favorable theoretical basis for effect evaluation and yield prediction after vertical well volume fracturing of the low permeable reservoir, and overcomes the defects of the prior art.

Description

technical field [0001] The invention belongs to the field of oil and gas field development, and in particular relates to a method for predicting the stimulation volume of a vertical well volume fracturing reservoir in a low-permeability oil and gas reservoir. Background technique [0002] Low-permeability reservoirs have poor physical properties, complex pore structure, low surface porosity, and small throats. It is difficult for conventional fracturing technology to achieve the expected production stimulation effect. Volume fracturing technology is an important technological measure to improve low-permeability oil and gas fields and increase production. Volumetric fracturing of horizontal wells is the main technical means for stimulation of low-permeability oil and gas reservoirs. However, the low-permeability oil and gas reservoirs in my country are mainly continental deposits. Developed low-permeability reservoirs have the characteristics of small accumulation area, many ...

AI Technical Summary

Problems solved by technology

Although the discrete fracture network simulation method does not need to obtain microseismic monitoring data and post-fracture production data in advance, the basic theory of this method is relatively complicated, the calculation amount is large, and the model convergence is poor, so it is not easy to implement

It can be seen that the existing reservoir stimulation volume prediction methods have certain deficiencies and are not suitable for large-scale application in field practice.

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