Shear seam shale core pulse attenuation permeability testing method

Abstract

The invention discloses a shear seam shale core pulse attenuation permeability testing method. The method comprises the following steps of: S1: establishing a dual-medium physical model of a shear seam shale core based on a multi-scale seepage model of gas in the shear seam shale core; S2: obtaining a finite volume discrete format corresponding to a physical model by using a finite volume method, solving a full-implicit solving format of the physical model by combining the Newton-Raphson iterative algorithm, and programming and solving the model; S3: performing a pulse attenuation experiment on the shear seam shale core by using a pulse attenuation method experiment device, and measuring a pressure and time relation curve of an upstream chamber and a downstream chamber by using the experimental data; and S4: combining the dual-medium physical model of the shear seam shale core, and acquiring the matrix permeability and the fracture permeability of the shear seam shale core by adopting a curve fitting method. The method can be used for testing the permeability of the shale core with the shear seam.

Description

technical field [0001] The invention relates to the technical field of shale gas development, in particular to a method for testing shear fracture shale core pulse attenuation permeability. Background technique [0002] From the perspective of global energy development strategy, the development of shale gas is changing the global energy pattern and becoming the focus of global development. It is predicted that the total resources of shale gas reservoirs in the world are about 456×10 12 m 3 , accounting for about 50% of the total resources of unconventional natural gas (coalbed methane, tight sandstone gas, shale gas). At the same time, exploration shows that my country's shale gas resources are very rich in recoverable reserves. [0003] At present, the United States has successfully carried out commercial exploitation of shale gas in many basins, but many problems have been exposed in the development practice in recent years, and many theoretical and technical bottleneck...

AI Technical Summary

Problems solved by technology

Bryant (2018) improved the traditional pulse decay method, reduced the number of pressure sensors in the device, and greatly reduced the cost of the test device. At the same time, the device has the advantages of convenient operation and high test efficiency. Effects of Scale Seepage and Adsorption-Desorption

[0006] The above methods can only be used for parameter testing of homogeneous cores, but not for shale cores with shear fractures. Therefore, there is an urgent need for a testing method suitable for shear fracture shale cores.

Images